TABLE OF CONTENTS Report on ithe Meeting for the Exchange of Into:nnation on El Tor Vibrio Paracholera Provisional Agenda List of Participants, Observers and Temporary Advisers Paracholera El Tor in the Philippines, 1961-1962 Epidemiologic Aspecte Wffi/Cholera 1 WPRVCholera 2 WPlt/Cholera 3 WPR/Cholera 4 WPR/Cholera 5 WPR/Cholera 6 WPR/Cholera 7 Wffi/Cholera 8 WPR/Cholera 9
An Epidemiological and Immunological Stuqy of El Tor Vibrio Paracholera in Negros Oriental, Philippines Remarks on the Epidaniology of the 1961-1962 El Tor Epidemic Some Characteristics of the El Tor Vibrios Isolated from the 1961-1962 Epidemic "Paracholera El Tor" Outbreaks in Indonesia f
The Treatment of Cholera Outlines of Prevention and Control Progrllllllle in Japan Against Parachole~a due to El Tor Vibrios, 1961-1962 Some Biological and Serological Characteristics of the Vibrio Strains Forwarded to us from Various Places in South As:!:a as the Causative Agent of the Socalled"Paracholera" Aspects of Clinical Management of Paracholera Patients A Report on the Cholera Outbreak in Sarawak
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WPR/Cholera 10 Wm/Cholera 11 Unnumbered Unnumbered Unnumbered
HEl Tor" Cholera in Thailand
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Eeference on Paracholera Note.
Due to a limited DIlJIlber of copies, the lWHO/WFRO Library was not able to obtain the following dOC1Dllents for inclusion in binding this volume. Reports on Outbreaks of El Tor Vibrio Paracholera. 1962 North Borneo Unnumbered :
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Cholera Epidllllics in the World During the Last Few Years (1955-1961)
REGiONAL
OFF1CE FOR 1iHE WESTERH PA.arac af •h-e·
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REPORT OM
rAE MEEnNG FOlR THE EXCHlANG!E OF I:HFORMATJQN OH IEL TOR VIBR~C PAA.ACHOI!.ERA
MEil!U!ING FOR THE EXCHANGE OF INFORMATION
ON EL TOR VIBRIO PARACHOLERA
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NOTE
The views expressed in this report arc those of the advisers and participants at the Meeting and do not necesBarily reflect the policy of the World Health Organization.
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This report bas been prepared. by the Western Pacific Regional Office of the World Health Organization for governments of Member states and for all who partiCipated in the Meeting for the Exchange of Information on El Tor Vibrio Pars.cholera, Manila, April 1962.
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TABLE OF CONTENTS
1. 2.
INTROWCTION
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1
DIAGNOSIS OF EL TOR v:nmIO PARACHOLERA
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2.1 2.2
2.3
Presentation of problems •••••••••••••••••••••••• Discussion ......................................................................... .. Summary of problems noted as related to diagnosis ............................................................................ ..
3 3 5
2.4
Conclusions
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5 6
EPIDEMIOLOGY Summary
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Observations ...................................................................... .. of observations ••••••••••••••••••••••••• Conclusions ........................................................................ ..
6 7 8
4.
PREVENTION AND CONTROL OF PARACHOLERA (m.ruNIZAfiON)
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9 11 11 12 12 12
4.1 4.2 4.3 4.4 4.5 4.6 4.7
Immunization with cholera vaccine ••••••••••••••• Immunization with TABC vaccine •••••••••••••••••• Controlled vaccine stUdies •••••••••••••••••••••• El 'lbr V'8.ccine .............. •,' ................................................. ..
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Use of bacteriophage and others ••••••••••••••••• Summar.Y of observations ••••••••••••••••••••••••• Conclusions •••••••••••••••••••••••••••••••••••••
13 13 13 14
PREVENTION AND CONTROL OF PARACHOLERA (SANITARY AND CY1'HER MEASURES)
6.
.................................... General control measures ........................... Discussion ....................................................... Conclusions ........................................................ ...................................................................... ..................................................... ........................................................ .................................................................... .......•• .......................................................... . . . . . . It . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . It . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . It . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . It . . . . It It . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
17 18 18 19 20 2l 2l
6.1 6.2 6.3 7·
Introduction Discussion Conclusions
RESEARCH
Presentation of fUrtber research needed DiSCUSSion Conclusions
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8.
mTER-caJNTRY CO-oRDINATION
8.1 8.2 8.3
8.4 8.5 8.6 8.7
Notification of occurrence Extent of infected local area ...•...........•... DiSsemination of information •••••••••••••••••••• Notification of freedom fram infection ......•... Restriction on foodstUffs and commoditie~ ....... Traffic not amenable to quarantine •••••••••••••• Conclusions .....................•.••............
'Z7 28 28 Z) 2)
29 Z)
TABLE OF CON'l'EN'l'S (Continued)
ANNEX 1 ANNElC 2 .ANNEX 3 .ANNEX 4
....................................... PROVISIONAL AGENDA ....................... PROVISIONAL SCHEWLE OF EL TOR MEEll'ING ••• LrST OF PARTICIPANTS'
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LIST OF DOCUMENTS
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1.
INTROOOCTION
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1.1 Enteritis cboleriformis El Tor, known as paracholera,l has occurred periodically in epidemic form in Indonesia over the past twenty-five years. Neighbouring countries bad remained free of the infection until the middle of 1960 when El Tor cholera vibrios were isolated in Bangkok towards the end of an outbreak of classical Asiatic cholera. At this time the isolates were cultured fran a few patients suffering from diarrhoeal conditions and fran samples of food and of water. In September of that year the first epidemic of cholera El Tor occurred in north-east Thailand. 1.2 Meantime, an epidemic which started on 5 January 1960 in Ma.cassar spread throughout the whole of Indonesia., a.ffecting Java in 1961. The infection appeared during July 1961 in Sarawak and thereafter Macao and Hong Kong were affected in August. Concurrently, paracholera was reported in the Province of Kwangtung in the Chinese Peoples Republic. The first cases of El Tor infection appeared in the Republic of the Philippines on 22 September; in January 1962, North Borneo was, in turn, affected. 1.3 This unprecedented occurrence in the region of epidemics caused by the El Tor cholera vibrios has pointed to the urgent need for a better understanding of the epidemiology, prevention and control of the disease. It was accordingly arranged that an M ~ meeting should be held in Ma.nila under the sponsorship of the Western Pacific Regional Office of the World Health Organization for an exchange of information between senior officers of the health administrations of the countries either affected by epidemics or at risk of the introduction of the infection. The purpose of the meeting was to pool knowledge and experience of the clinical management of patients suffering fran El Tor infections, of the prevention of the spread of the disease and of its control, once established. It was also thought desirable to invite advisers in the various fields of cholera treatment, research and control so that the health administrators concerned would have available to them a wide range of experience and information of the present state of knowledge of cholera. 1.4 Invitations to governments for the ncmination of suitable participants and to the prospective advisers of the meeting were sent out in the early part of February 1962. The responses received fran the governments as well as the advisory group, were most gratifying. The WHO Headquarters in Geneva assisted in the supply of available literature and in designating the Chief Medical Officer in charge of international quarantine to attend the meeting. 1.5 The WHO Regional Offices for South-East Asia and Eastern Mediterranean also responded favourably by inviting participants fran Indonesia, Thailand. and East Pakistan. Sane governments sent additional
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lPrior to the adoption of an official ncmenclature, the present outbreaks are variously referred to in this report as El Tor vibrio parachol.era., enteritis choleriformis El Tor, or cholera El Tor. Classical cholera is referred to also as cholera Asiatica •
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- 2 participants at their own expense... Observers fran the Philippines, the United States Armed Forces, the Agency for International Development and the Pakistan-BEATO Cholera Research Laboratory also took part in the meeting. 1.6 The meeting was held in Manila fran 16 to 19 April 1962. It was opened by Dr. I. C. Fang, Director, WHO Regional. Office for the Western Pacific, who expressed the objective of the meeting as one for the exchange of information on this dreaded disease. He reminded the group that it was in the wake of the pandemic sweep of cholera that international. solidarity in health was born, and informed those present of a meeting of the WHO Scientific Group on Cholera Research that bad taken place in Geneva the week before. 1.7 In his opening remarks, Dr. D. J .M. MacKenzie, as the Director of the meeting, posed numerous questions of a practical nature relating to the pathogenicity of the disease process, its treatment, the interpretation of a laboratory diagnosis, the evaluation of the vehicles of. transmission and the role of the contact carrier in the dissemination of the infection. The importance of the infected family as the epidemiological unit was stressed as was the fact tbat it would be indefensible in the present state of our knowledge to discard the use of cholera vaccine as a cc:mnunity protective measure. He stated that whether or not cholera El Tor is to be considered a quarantinable disease, much thought is needed on the dissemination of information, the early warning of the appearance of cholera vibrios in a community and the effective measures that can be applied for protection without undue dislocation of legitimate trade and travel. In connection with quarantine, two points of fundamental importance were put forward for consideration: the definition of the size of an "infected local area" in the context of cholera and the scope of the restrictions to be placed on commodities which are likely to be vehicles of infection when imported frcm infected countries. There was an urgent need for further field and laboratory research into the epidemiology of cholera infections I&Jld for the wide and speedy dissemination of information. The purpose of this meeting would be achieved, he asserted, if agreement could be reached on general lines of action that are applicable 1n practice to local circumstances as they apply to urban or to rural communities infected. 1.8 The meeting was conducted in plenary sessions throughout. Each item of the agenda was introduced by the respective adviser or advisers on the panel, the introduction lasting for scme ten or fifteen minutes; the participants were then invited to comment and to raise questions directed at other partiCipants or at the panel. All presentatiOns and discussions were recorded on tapes and records were kept of the time and the tape-recorder counter~umber of each contribution. 1.9 The report that follows summarizes the total contribution of the group and the general conclusions reached by the participants.
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DIA<If08IS OF EL TOR VIBRIO PARACHOLERA
i 2.1 Presentation of problems The Cba.1rma.n and one of the Advisers outlined the problems encountered during the present epidemic of El Tor paracholera. Reference was made to the publications of Mukerjee and Guba Roy (Brit. M.J., 1:685, 19(2) and of workers in the Philippines (Briones, Aragon, Pesigan - in print) on the characteristics of the El Tor vibrios isolated in Hong Kong and in the Philippines. Tabled at the meeting was a memorandum-report on tbe "Identification of vibrios associated witb tbe Hong Kong epidemic of cbolera, 1961" fran K. Goodner, H.L. Snitbl Jr. and H. stempen, Jefferson Medical College of Phil adelphia. Most fre~ently rectal swabs were examined. In Hong Kong, a small glass -spoon inserted into the stopper of the enricbment fluid was used instead of swabs. AlkaJ.ine peptone broth with or without potassium tellurite and, more rarely, Venka.tra.ma.n and Ramakrisbnan's preserving medium were employed to ship the specimens to the laboratories. The plating media used were a.l.ka.l.ine agar witb bUe salts in Macao, Hong Kong (duplicate plates), Indonesia, Sarawa.k and North Borneo; Hynes' agar in Sarawak and North Borneo; Dieudonne I s in Macao, Indonesia and, in the beginning, in ManUa. Two laboratories in the Philippines switched to Monsur's modification of tbe tellurite plate. One of them used first the Smith and Goodner medium, adopted subsequently Lanksford's stereomicroscopic metbod, and after that, Yen's plate.
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The sera employed for the differentiation of agglutinable vibrios came from at least five sources. Most of tbe vibrios whicb were agglutinable beJ.onged to the Oga.wa subtype and the majority of them gave a positive Voges-Proskauer test. All were insensitive to MukerJee's group IV phage which is a characteristic of El Tor vibrios. The overwbel.J:ning majority of the cultures formed measurable amounts of haemoly.sin. This characteristic sometimes faUed to reveal itself during the first subcultures of the organisms. It was the opinion of the Adviser that the nomenclature of this El Tor strain should be reconsidered and V. chol.eoe El Tor or V. ccmma. El Tor used.
2.2
Discussion
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In the diSCUSSion, it was noted that in Taiwan the value of the starch agar pla.tes'las confirmed a.nd p~ typing was emphasized as a method of choice. The laboratory workers there were successful in isolating pba.ges f'ran stock cholera vibrio and fran recently received El Tor cultures. The phage suscepUbU1ty was helpful in selecting strains for va.ccine preparation.
- 4 One of the participants frem Japan was in favour of using the designation V. cholera.e var. El Tor. He found active ha.emolysin production and good agglutinability but same strains belonged to Heiberg group IV. Of other methods recommended for the differentiation of "true" cholera and E1 Tor vibrios, the soda agglutination test of Ta.namal proved to be reliable. One participant fram. the Philippines confir.med that ha.emolysin production fluctuated especially with the age of the culture. Heat inactivation and the Tanamal tests were not helpful. in his laboratory. One observer fram the Philippines spoke in favour of the a.l.kaJ.ine bile agar plate and stressed the long survival time of E1 Tor vibrios in sea-water (10 days) and in shallow well-water for l~ days WbUe stock cultures of cholera vibrios died in the latter after two weeks. The participant fram Pakistan spoke in favour of the Monsur plate. He was satisfied with the results of the ha.emol.ysin tests and added that further trials of phage typing were desirable. The partiCipants fram Taiwan, the Philippines and Pakistan agreed that ha.emolysin tests with sheep cells were constant and reliable. The participant fram North Borneo emphasized the importance of studies on the survival time of vibrios. One of the participants fram Thailand underlined the urgency of early diagnosis on one band and stressed the difficulties resulting from the overflowing laboratories which are a cammon sight during cholera epidemiCS on the other.
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In the discussion on nomenclature, the participants fram Indonesia and the Philippines were strongly in favour of calling the organism and the clinical entity "paracholera ". The majority of the participants did not concur and this was supported by the Chair and the Advisers. They suggested to the meeting that the present confusion arising frem variations in bacteriological nomenclature could be resolved best by the International Committee on Bacteriologieal NOmenclature which will meet in Montreal, Canada., later this year. It was agreed that the great variety of media in use for the collection, preservation, shipping, enricment and primary plating of stool specimens and rectal swabs was confUsing and gave rise to differences in interpretation. It was also agreed that the causative strains may vary in different epidemics so that the laboratory techniques during one outbreak may not be fully applicable to another. The nomenclature of the strain of vibrio causing the present El Tor outbreak was discussed and d:lesgreements concerning its biochemical and physical properties noted. This strain seemed to undergo variations with ease but its survival under natural conditions appeared to be longer tlBn that of other cholera vibrios. The main differentiating characteristics of the El Tor vibrios isolated fram this outbreak may be sUllllll8.l'ized as haemolysis of sheep red blood cells and a lack of susceptibility to group IV cho1era pbage, with most organisms belonging to the Ogawa serologic_subtype.
- 5 Summary of problems noted as related to diagnosis
Tbe meeting noted: 2.3.1 2.3.2 Tbe need for more precise nomenclature in respect of agg!utinable cholera vibrios. The importance in the early diagnosis of cholera of the methods used for the collection and transport of specimens fram rural areas to the laboratory. The urgent need for better standardization of laboratory methods for the collection, shipment and primary identification of agglutinable cholera vibrios. This entails general acceptance of more uniform methods of preparation of media and a comparative study of the efficacy and selectivity of rectal s~~bs and faecal specimens in establishing a diagnosis.
2.3.3
2.3.4
That the methods of assessment of haemolysin, agglutinability and antigenicity of strains required urgent study in the light of the techniques employed and their reliability. That methods in use for the serologic diagnosis of cholera El Tor should. be assessed, particularly in relation to antigenic structUl:e and antibody response as compared to classical cholera. That phage typing was a technique of promise which should be investigated further with a view to its wider use and more precise standardization. That it is very desirable to designate a central laboratory or laboratories so that uniform reliable diagnostic sera. may be made readily available to national laboratories. Conclusions The meeting concluded:
2.3.5
2.3.6
2.3.7
2.4
2.4.1 .:
That it is urgent to have a clearly understood and generally ~ccepted classification and nomenclature.of cholera vibrios and that this question of nomenclature should be referred by liRO to the International Committee on BacteriolOgical Nomenclature which will meet in Montreal later this year. That early consideration should be given to the establisbment, under WHO sponsorship, of a. central cholera phage service reference laboratory and of a central source of supply of other s~ reagents used in the diagnosis of cholera • That national laboratories should review the methods in use for the collection and shipment of specimens collected in the field for the early primary ident~ication of agglutina.ble cholera v1brlcs, with a view to achieving more uniform results on which epidemiological action is based.
2.4.2 •
2.4.3 ft
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- 6 3. 3.1 Observations
EPIDEMIOLOGY
The Chairman and two of the Advisers summarized the problems in epidemiology which the current El Tor epidemics presented. The first problem was the lack of materials and adequate laboratory facilities necessary to cope with the tremendous influx of spec:lJnens. Another problem was the method of isolating vibrios. In the beginning, the so-ca.lled Macao method was used, bu.t later modifications, new media and procedures were added, scme of which were employed. without comparative field tests. This made it difficult to compare the results obtained in various laboratories. A considerable amount of current research work was performed, especially in the Philippines, which is to be published in due course.
Attention was given to the rates, distribution and role of contact carriers in the transmission of El Tor infections. The host factors were listed and the frequency of distribution in the adult age groups was emphasized. Males and females were affected in about equal proportions. The attack rates were observed to vary in different communities presumably due either to host or environmental factors. The meeting was given an outline of the results of investigations in the Philippines. The epidemiology pointed to water, fish and other foods as possible vehicles. Two types of epidemics were observed: (a) the explosive, proven water-borne epidemic with large numbers of clinical cases occurring within .a relatively short period of t:lJnej (b) the slowly progressive epidemic, with relatively fewer cases occurring over a longer period of t:lme and characterized by high family infection rates. A constant observation was that the infectiOns appeared earlier and the attack rates were highest amongst population groups living on the sea coast and on the shores of inland lakes. Inland cammlDities were affected later and to a lesser extent.
Most of the clinically apparent cholera El Tor cases in the Philippines were not vaccinated. The proportion of vaccinated to nonvaccinated patients, however, corresponded to the ratio of vaccinated to non-vaccinated persons in the total population. Reports on recent outbreaks in the Philippines, Hong Kong, Sarawak, North Borneo am Indonesia were available to the participants. The participants tram these countries and fram Macao highlighted points
of epidemiological interest. It was noted that the lower socioeconomic groups with poor standards of sanitary facilities were attacked by El Tor disease. Those affected were predominantly either boat or waterside dwellers. Water in sane instances was proved to be the vehicle of infection, and in other instances, seafood eaten raw was suspected. In one outbreak evidence pointed to vegetables as the source of infection. Flies as transmitters of the disease were also mentioned. but the consensus of opinion was that man and water polluted
- 7 by man were the chief means by which the epidemics spread. Note was taken of the explosive epidemics with high fatality rates which followed festivals and funerals of patients who had died of paracholera. Throughout, the age groups most at risk were predominantly adult with higher fatality rates in older people. This was suggested as being due to lack of herd iImnunity and to greater risk of exposure, the contrast being noted that in epidemic areas, such as in East Pakistan, children are the main sufferers. There were no significant differences in the attack rates according to sex. Dietary habits and standards of nutrition which may predispose to clinical infection were discussed. It was ventured that Malaya, where general health and economic conditions have improved rapidly during the past years, may have remained free from cholera because of improved nutrition. Little was known about the survival of the vibrios during inter-epidemic periods in non-endemic areas. The El Tor vibrio is, however, known to be a sturdier organism than its classical counterpart. Animal hosts, other than man, have not yet been implicated. Investigations during recent epidemics indicate that contact carrier states in El Tor infections average between 7'fo and 8'1>. The duration of the contact carrier state was relatively short but had not been precisely determined. '!be importance of these carriers was emphasized repeatedly during the discussiOns. The need for further research into the carrier state was agreed to be urgent. A violent outbreak of diarrhoea of unknown origin on island south of Biak was mentioned. Pathogenic vibrios were isolated fran the persons involved. Attention was called to necessity for early investigation, especially of . such local of gastrointest1naJ. disturbances and of atypical cases which unrecognized cholera. a small not the outbreaks may be
The histories of past cholera epidemics in Thailand, Korea, Japan and Singapore were recounted and the great concern of these countri es as well as of Malaya about the present risk of invasion by infections was expressed. The meeting noted that the Scientific Group on Cholera Research bad met in Geneva early in April 1962 and agreed with the opinion expressed by the Scientific Group that clinically and epidemiologically cholera El Tor was indistinguishable from classical cholera.
3.2 3.2.1
Summary of observations During the recent outbreaks two epidemic types could be identified : (a) explosive epidemics arising from presumably cammon vehicles of infection, in same cases water;
(b) ~.2.2
progressive and insidious epidemics characterized by high family infection rates.
The lowest socio-econcm1c groups which bad low standards of sanitary facilities and which were predominantly boat, waterside or alum dwellers had been affected. A cammon article of
diet under suspicion was seafood. Investigations during recent epidemics indicate that contact carrier states in El Tor infections average between 7% and 8%. The duration of the contact carrier state was relatively short but had not been precisely determined. Flies mB¥ play a significant part in the transmission of infection and cholera vibrios bad been isolated from flies during an epidemic in Indonesia. Those persons most at risk during the epidemics described were predaninantly in the older adult age groups and there was no significant difference in the attack rates in the two sexes. Young children showed the lowest attack rates. ~.2.6
Little was known about the survival of vibrios during interepidemic periods in non- endemic areas where El Tor vibrios can be isolated. The El Tor vibrio is, however, known to be a sturdier organism tban its classical counterpart. The Scientific Group on Cholera Research which met in Geneva
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during the first week of April was of the opinion that clinically and epidemiologically cholera El Tor was indistinguishable from classical cholera. }.~
Conclusions The
meeting concluded:
3.}.1 }.3.2 ~.3.}
That the contact carrier plays a significant role in the transmission and dissemination of cholera El Tor. That the lack of protected water supplies and low standard of sanitation greatly increase the risk of cholera El Tor. That boat, waterside and slum dwellers of the lowest socioeconomic group have been almost exclusively affected. That from the ep1dem:l.ologiAl. standpoint cholera El Tor and cholera Asiatica are indistinguishable.
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- 9 4. PREVENTION AND CONTROL OF PARACHOLERA (DHJNIZATION)
4.1 •
Immunization with cholera vaccine Efficacy
4.1.1
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In opening the discussion the Chairman remarked that almost every known method of preparation of anti-bacterial vaccines bas been applied to cholera vaccine. The standard. cholera vaccine now in use, containing the somatic antigens of combined Ogawa and Inaba strains, has been widely assumed to bave protective properties in the presence of endemic or epidemic cholera, but this bas never been proved conclusively. Its effectiveness as a community protection measure has been challenged, especially against cholera El Tor, both on laboratory and epidemiologic grounds. However, it is of fundamental importance to ensure tbat this measure, widely used in practice, is not discarded lightly until such time as scientif1ca1ly controlled vaccine studies have been undertaken and assessed. It is of equal importance to maintain public confidence in a preventive measure which has achieved world-wide usage and international sanction. It seems unlikely that those who quite sincerely profess doubts on scientific grounds would be prepared to advise national health authorities to discard an epidemiological tool of accepted practical value in the present state of knowledge and in the face of threatened or of epidemic cholera. In discussion it was agreed that the immunity conferred by a bacterial vaccine may be expected to break down in the vaccinated
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person exposed to a large inoculating dose of a virulent natural infection. That this may happen with cholera Asiatica or cholera El. Tor is undoubted.
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Experience of the use of stands.rd cholera vaccine, particularly during the present series of epidemics in the Region. gives support to this belief. Nevertheless, there is a strong body of opinion that vaccination against cholera will modify the disease in those ill with cholera and will shorten the duration of, or even halt, an epidemic. This is provided that the percentage cover achieved in an infected caumunity is sufficiently high to confer a substantial degree of herd immunity. It is confidently believed by those with experience in achieving an average of 80% of persons inoculated in the community at risk that the clinical disease quickly disappears and that there is a possibility that the contact carrier rate may also be diminished. Mass immunization campaigns in Pakistan, Sarawak, North Borneo, Macao and. Hong Kong where an average of between 5CJ!, and &I{o of the groups most at risk were inoculated gave support to this belief. In Japan, an investigation carried out in 1946 showed. that, wnongst vaccinated persons, only 29i contracted clinical disease whereas the morbidity rate was 7CJ!, in the unvaccinated; the Japanese health authorities believed that cholera vaccination was effective in protecting against severe clinical manifestations, but it did not prevent the development of contact carriers. The experience in the
- 10 Philippines was that attack rates in a closed community infected in the National Mental Hospital were statistically and significantly higher in an unvaccinated group. There was, however, no significant difference in the case fatality rates between the vaccinated and unvaccinated. The provisional conclusion was that cholera vaccination reduced morbidity but appeared to have no influence on mortality amongst those who developed severe clinical cholera El Tor.
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4.1.2
Dosage of immunization
The immunizing dose for the adult was accepted as 1 ml of vaCCine, given subcutaneously, containing 8000 million organisms. In children, experience in Hong Kong had indicated that 1 ml of vaccine could be given to children over the age of five years and that 0.5 ml caused no reaction in the age group 01' 1 to 5 years. Children under one year were not given vaccine. There were no contra-indications other than the presence of an acute febrile illness. In Malaya, Sarawak and North Borneo, cholera vaccine had been given intradenzaally in doses of 0.2 to 0.3 ml of standard vaccine. During the epidemics in the two latter countries there bad been no difficulty in obtaining staf1' competent to use the intradermal" technique which had been adopted owing to a shortage of vaccine. Reference was made in this connection to a publication of the Institute for Medical Research in Malaya.2
The administration of two doses of cholera vaccine at an interval of seven to ten days in 0.5 ml and 1 m1 doses, respectively, was agreed to be immunologically sound, but not always practicable. In dealing with very large numbers of people, particularly during epidemics amongst the lower socio-econanic groups, it was not possible to employ the two-dose method at the prescribed intervals and the onl.y practical method was to give one dose of vaccine adjusted according to age. It was noted that the dosage and method employed were a matter for decision by the health authorities concerned and that this was accepted for international certificates of vaCCination against cholera for the purposes of the International Sanitary Regulations.
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4.1.3
Duration of immunity
There was considerable difference of opinion regarding the quality and duration of the immunity conferred by cholera vaccine. For all practical purposes, however, it was agreed that to maintain a protective level of antibodies re-vaccination should be carried out every six months, again using one dose of standard cholera vaccine given by the technique favoured.
2 Green, R., Medical Circular No. 37, Institute for Medical Research, KUala Imnpur, Ma.ls.ya, December 1954.
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4.1.4
Priority group for immunization
In the presence of threatened or actual epidemic cholera Asiatica or cholera E1 Tor, the priority groups to be immunized were agreed to be the lower socio-economic groups living under insanitary and overcrowded conditions, particularly boat dwellers and the inhabitants of waterside communities and slum areas. For this purpose, in centres of population, fixed inoculation centres are convenient and appear to be effective in attracting people to come forward for inoculation. In rural and coastal areas, mobile teams are essential to deal with relatively small village or sea dwelling groups.
4.1.5
Equipment
Only simple equipment is required, sterilization of syringes and needles by boiling is readily carried out and the dosage of vaccine can be readily adjusted by using syringes. In large exclusively adult population groups "jet guns" may be used and inoculations at the rate of 1000 an hour can be achieved. This apparatus does not allow immediate adjustment of the dose and. would not a.ppear to be suitable in groupS where children accompany the adults. 4.1.6 Availability of vaccine
It was noted that in the recent epidemics of cholera El Tor the public demand for vaccination had outstripped the supply of vaccine and that there was need for information on a regional basis of sources of vaccine and its availability. The WHO Western Pacific Regional Office in Manila already bad this in hand and was compiling a list of national laboratories which manufacture standard cholera vaccine. In addition, information had been sought regarding quantities of vaccine immediately available and the cost. WHO is not a supply agency and could not of itself make vaccine available free of charge. Its role was to provide information, facilitate distribution within the resources available to the Organization and to provide technical advice and assistance whenever it was sought. 4.2 Ewmunization with TABC vaccine
"'.
The place of TABC vaccine received mention as it bad been used during recent epidemics. It was, as a general rule, not well accepted during mass emergency campaigns owing to the more severe local and systemic reactions to inoculation. 4.3 Controlled vaccine studies
It was unanimously agreed that there is an urgent need for controlled vaccines studies and that the ·success of early treatment by the replacement of body fluids and electrolytes would overcome any ethical considerations arising in control groups. A double-blind trial USing vaccines of varying antigenicity, matched against results in control groups, was necessary and should be applied only in Ii community where cholera re-appeared after an absence of several years.
- 12 4.4 El Tor vaccine
The use of vaceines produced from El Tor strains was also considered a.nd it was agreed that more thought should be given to this aspect. It was known through animal experiment that undesirable local and systemic reactions could occur with El Tor vaccines.
4.5
Use of bacteriophage and others
Consideration was also given to the place of bacteriophage in prevention, the role of material "x" as described by Phillips et a1 and the possibility of the developnent of an anatoxin. The problem of the antigenic structure of surface antigens in relation to vaccines prepared respectively fram cholera Asiatica and cholera El Tor strains also received mention. It was noted that the haemolysin present in El Tor strainsh8.d nothing in cammon with the clinical manifestations of cholera. 4.6 4.6.1 Summary of observations
VaCCination, USing standard cholera vaccine of 8000 million organisms per ml, is a camnunity protective measure that must be retained. Until such time as controlled vaccine studies have been completed and the efficacy of standard vaccine assessed, it would be indefensible to consider any recommendation to discontinue its use. There is a strong body of opinion that vaccination against cholera will modify the disease in those subsequently i l l with cholera and that it will reduce attack rates in the vaccinated group. The one dose regimen of vaccination against cholera is the
4.6.2
only practical method of mass immunization of the low socioeconomic groups most at risk. There are no contra-indications other than an acute febrile illness.
4.6.4
Experience indicated that to produce an adequate ~ ilDnunity, the aim should be to vaccinate at 1eastB~ of the groups most at risk. Where this has been achieved· during the recent outbreaks, epidemics have quickly come to an end. The regimen and techniques of vaccination employed were a matter for decision by the health authorities concerned. Revaccination should be carried out after an interval of six months, pending controlled vaccine evaluation studies. Priority in mass vaccination campaigns against cholera should be given to boat dwellers, waterside communities and the lowest socio-ecollomic groups living under slum conditions. There is a need for information on a regional basis regarding sources of supply and availabUity of cholera vaccine and tbat the WHO Western Pacific Regional Office was a.l.ready compiling t.bia information.
4.6.5 4.6.6
•
- 13 -
4.6.7
The possible use of cholera vaccine manufactured. from El Tor strains required further study, but was not recommended as a practical measure until more is known. Conclusions The meeting concluded:
4.7
4.7.1
That mass inoculation campaigns using standard cholera vaccine must be continued as a community protection measure in the face of threatened. or epidemic cholera. That priority in vaccination campaigns should be given to boat , dwellers, to waterside camnunities and to those living under slum conditions. That to achieve an adequate degree of herd immunity by vaccination, the aim should be to vaccinate at least 80% of the groups at risk. That there is an urgent need for controlled vaccine evaluativn studies to either prove or disprove the efficacy of standard cholera vaccine.
4.7.2
4.7.3
4.7.4
5.
PREVENTION AND CONTROL OF PARACHOLERA (SANITARY AND OI'HER MEASURES)
5.1
General control measures
•
In opening the discussion the Chairman observed that in any problem of prevention and control there are general principles which w'ill apply in part or in whole to any formidable epidemic disease. While a diagnosis on general clinical grounds must initiate immediate action, particularly in rural area.s, early confirmation in the laboratory will indicate the extent of the measures of control and of prevention of spread that will follow. The clinical diagnosis implies notification, the prompt isolation of the patient, the identification of contacts and their segregation or surveillance, whichever is appropriate. Disinfection of fomites and premises, intensive measures of environmental nygiene and an appropriate mass immunization of those at risk will follow. To keep the public fully informed throughout is of vital importance and the cr~nnels and media of information w'ill vary according to local circumstances. This stimulates interest, may relieve anxiety and if adequately presented at the proper level of understanding, it enlists co-operation. The health teams working on control measures must never forget, in conjunction with other measures, to try to gain the confidence and co-operation of the group affected by a simple explanation of the disease process and the environmental factors that favour the harbouring of infection and the promotion of its spread. THider epidemiological investigation involves the search for a vehicle of infection, be it vector, intermediate host, carrier or same cammon dietary factor. Finally, there is the establishment of permanent or semi-permanent control measures, if necessary~ backed.
- 14 by statutory powers dealing with the protection of water supplies, sewerage, building construction and other relevant environmental factors. Emergency legislation may be necessary for compulsory immunization and for regulations governing notification, the isolation of patients, segregation or surveillance of contacts, the cleansing of premises and the disposal of the dead. The application of these principles to cholera will give a pattern of control measures all of which may not be always fully practical or possible under the local conditions of the area or group affected. Control measures must be applicable with due regard to local custcms, traditions and economies. Given a pattern, there is scope for improvization and ingenuity, more particularly 1n scattered rural communities. It was emphasized that the control of cholera is a much more straightforward problem in a large urban area with adequate emergency facilities to band. To cope with an epidemic affecting scattered village communities in under-developed areas with virtually no sanitation, with long and difficult lines of camnunication and very inadequate health services is an entirely different problem which demands much improvization and ingenuity. Most important, there is a largely undeveloped field of propbylaxis to be explored which will be canplementary to immunization with cholera vaccine.
+
5.2
Discussion
In discussion, for the purpose of formulating a pattern, it was assumed that under present circumstances cholera El Tor will appear with little or no warning. It was agreed that early notification of cases of acute diarrhoeal disease is the key to control and prevention. The role of village management and local government bodies is important in this connection and the inoculation of a public awareness of the dangers of cholera is of prime importance in ensuring early notification. In sane groups the concealment of cases and the irregular disposal of the dead must be taken into account. For example, amongst boat dwellers the "dumping" of bodies at sea is to be antiCipated if cholera, which is well known to them, is suspected. This may be the first indication that something is amiss. It is in the context of awareness and early notification that public information through the press, radio, posters, handbills and other visual aids can be most rewarding provided that the material is well chosen and reliable individuals are available in the camnunity concerned to act as two-way channels of communication. 5.2.1 Early notification
It was noted that in scme countries with widely scattered population groups, particularly island communities, notification of cholera or' suspected cholera may take up to three weeks to reach the central health administration. By this time sma.11 local epidemics may be over but the infection is widely seeded in adjoining ccmnunities. The lack of trained health staff at all levels and the thinly and widely spread resources available meant that, until local health administrations can be greatly strengthened, continuing epidemics of cholera can be
expected.
- 15 Reference was made to the barrio organization in the Philippines where a health councilman was responsible for advising the health authorities regarding the occurrence of notifiable diseases. In East Pakistan, village school teachers and others of equivalent educational level were encouraged to assist in notifying acute diarrhoeal disease and to send in stool specimens.by post, to a central laboratory, in containers easily distributed in which was a rectal swab and a quantity of fluid medium which maintained cholera vibrios for periods up to 14 days. The meeting noted that the media prepared according to Monsur, Venkatraman Ramakrisbnan, Gobar and Ma.kkabi, Wilson and Reilly, Refeore and Gallut were all proved to be reliable in practice. 5.2.2 Confirmation of laboratory diagnosis
•
Early confirmation in the laboratory of agglutinable cholera vibrios was essential to support a clinical diagnosis. The presence of agglutinable cholera vibrios was agreed to be the signal for urgent control measures to follow and support action based on a clinical diagnosis. There was a need ~o designate national laboratories throughout the Region which adopted standard techniques for the identification of the isolated strains either based on the existing pattern, such as that recommended by Pollitzer (1959) and adopted by WHO, or other procedures to be accepted in the future. A comparison of the various media used for collecting specimens in the field and the methods of transport to central laboratories should be undertaken with a view to de~eloping a cheap, uniform, quick and effective means of laboratory confirmation of suspected cholera. 5.2.3 Early isolation and treatment
The importance of the early isolation of clinical cases and their treatment in rural areas was discussed. Experience in Sarawak, North Borneo and the Philippines bad shown that emergency field hospitals and mobile treatment teams can be set up-qUickly and inexpensively. Simple eqUipment and supplies which are not bulky and are easily transported can be used. Thereafter, improvization on the site will give adequate means of effective treatment without the necessity of relying on bulky and weighty intravenous preparations which have to be transported and replenished. Plastic containers and infusion sets can be kept in stock and are easy to distribute. Handy standard packs of the necessary electrolytes can \I~ used to make up intravenous fluids on the spot which can be used effectively to save life. 5.2.4 Management of contact carrier
The management of the infected family group as the epidemiological unit and the treatment of the contact carrier were agreed to be of prime importance in the prevention of the, spread of cholera. In Hong Kong the adult contact carrier had been given 1 gm of oral streptomycin hourly for eight hours on an empty stomach and, with two exceptions, cholera vibrios had apparently disappeared from the bowel within a matter of hours. Children had also been treated sjmilarly .
- 16 with reduced doses according to age. streptomycin given orally had the advantage of being non-toxic by this route and there was little or no side effect. Two El Tor strains had proved to be resistant to streptomycin but the strains concerned were rough with possibly reduced invasive powers. These had responded to full doses of chloramphenicol. While this work had been done in a quarantine centre, it had a wider application in remote rural areas where the family tended to remain near or accompany the clinical case under treatment. Under such circumstances, the administration of streptomycin or same other agent to which cholera vibrios were sensitive might replace the quarantine of contacts in areas where such facilities were not available. It was noted that cholera vibrios were generally insensitive to sulpha drugs. These preparations would not appear to have a place in the prophylaxis or management of the contact carrier. 5.2.5 Sanitary and other environmental measures
•
t
The appropriate sanitary and other environmental measures to be taken were noted. The :importance of ~er as a vehicle of infection was well known and the methods of disinfection to be applied were
s1mp].e. Sea foods generally were under suspicion and epidemics have been known to occur as the result of the consumption of spoiled or discarded vegetables. Attention was drawn to the need to investigate further the persistence and survival of cholera vibrios in cammon articles of diet. This could be pursued best by national. health authorities with the necessary laboratory and other facilities. Intensive health education by all concerned in cholera control regarding the necessity to boil unprotected domestic water supplies, to cook sea foods and vegetable thoroughly before consumption and to practise the rules of elementary personal hygiene was essential. During an epidemic emergency, the public was usually responsive and much could be done to minimize the risks of transmission if all medical and health personnel played a continuing active part in simple health education. The development and improvement of protected water supplies and sanitary facilities related to community circumstances and the general economy was underlined. Given safe water and adequate disposal
T
of night-soil throughout the caamunity, the risks of cholera infections diminished rapidly. The ccmpe.rative costs of a campaign to control and prevent cholera and of a rural sanitation prograane, when related to the recent attack in the Philippines, indicated that it cost much less in the long run to provide permanent health assets in the way of protected sources of domestic water and proper systems of disposal of human wastes. The influence on the incidence of other gastrointestinal. diseases of importance was also considerable. An outline was given of the five-year programne undertaken by the Govermnent of the Philippines to construct safe wells and sanitary latrines in the rural areas. There was reference to the :importance of high standards of environmental sanitation in markets, the supervision of eating houses and food stalls, the role of itinerant food vendors in the transmission of cholera, particularly at public gatherings and festivals, and the
•
- 11 control of fly breeding. Cholera vibrios have been recovered fram flies and the necessity to cover fresh and cooked foods during an outbreak of cholera was stressed. •
S]?ecial mention was made of the burial of patients dying of cholera. Certain explosive epidemics with high fatality rates had occurred in Sarawak and the Philippines as a direct result of the burial customs and the traditional feast thereafter. Close physical contact with patients who had died of cholera appeared to give rise to particularly virulent infections in others and it was suggested that regulations regarding the burial of those dead from cholera would be tfmely. Certain countries had legislation which gave health authorities power to impose conditions under which burial took place. It was agreed that this was properly a decision for the country health authority concerned. 5.2.6 Prevention of introduction of cholera
The prevention of the introduction of cholera from infected countries to neighbouring states at risk was discussed. In Japan and Hong Kong special attention was being given to the ilIImunization of population groups living in small boats plying the coastal waters, crews of ships, port employees, transport personnel and others eIJ88.ged in dockside or waterside occupations. Until conclusively proved otherwise, the immunization of these groups with standard cholera vaccine was believed to be a logical first line of defence against the introduction of cholera.
It was mentioned that some countries, e.g., Sarawak, when affected with the El Tor epidemic, carried out vaccination of persons leaving the country in order to protect other areas. 5.3 5.3.1 ConclUSions The early confirmation in the laboratory of a clinical
diagnosis of cholera is of vital fmportance in its prevention To this end health administrations are urged to designate a central laboratory in each country in which uniform methods of diagnosis are employed. Attention was drawn to the WHO accepted standards of identification which appear as an appendix tn the publication by Pollitzer (1959).3 and control.
5.3.2
A sense of public awareness of the nature of the risks of cholera and of its prevention and control is essential for the success of any programne. To this end health education in the simple rules of personal and domestic hygiene will greatly minfmize the risk of infection whatever the environmental conditions. This should be an activity which is an integral part of the medical and health work of all those engaged in cholera control. Attention was drawn to the economies of permanent measures to provide safe water supplies and sanitation which are simple and are related to local circumstances. The cost of controlling
5.3.3
3See WHO Monograph Series No. 41, CHOLERA - R. Pollitzer (l9~).
- 18 country-w1de epidemics o~ cholera can ~ar exceed the total cost o~ annual capital expenditures on such projects spread out over a period o~ years. In this the WHO Regional Of~ice is willing and able to help with advice and technical guidance.
5.3.4
The prOvision of mobile treatment units and temporary field hospitals ~or the isolation and early treatment of clinical cholera in scattered rural areas, using simple easily transported equipment and supplies, bas proved to be success~ am practical. The maDBgement o~ the infected family group as the epidemio-
5.3.5
logical unit am the treatment o~ the contact carrier may be the key to prevention and control during an epidemic, particularly in rural areas where quarantine facilities are mintmal or do not exist.
5.3.6
In view of the explosive and letba.l epidemics arising directly fian this source, consideration should be given by country health administrations to the regulation of burial rites and customs for persons who bave died of cholera. The importance of the strengthening of health administrations in rural areas with poor cammmications cannot be overempbasized in the prevention and control of cholera.
5.3.7
•
6. 6.1 Introduction
TREA'lMENT
In introducing the discussion the Adviser said tbat cholera El Tor and cholera Asiatica present identical clinical manifestations of massive diarrhoea, and fiequ.ently, vaniting, with severe debydra.tion. The disease process, while not completely understood, is known to be self-limiting; therefore, the treatment with fluid and electrolyte replacement is supportive rather than curative.
6.1.1
Need for adequate and early treatment
will result in a low mortality rate.
General experience bas shown that adequate and early treatment Indeed, in uncomplicated patients there should be no death from cholera. 6.1.2 Basis of treatment
The electrolyte deficit in cholera is isotonic in nature with large losses of bicarbonate and potassiUlll. The pb;ys1ologic replacement o~ these losses is the basis for treatment. The most ef~icacious choice for a fluid regimen has been found to be 3 litres of isotonic saline to 1 litre of '2$ sodium bicarbonate.
.,.
-19 6.1.3 Determination of plasma protein concentration
Any regimen must be simple in design and ~imp1e to accc.mplish even under the most primitive field conditions. The copper sulfate method for determining plasma protein concentration bas been established as the most effective guide for estimating dehydration. The amount of fluid replacement can be Q.uickly and accurately calculated upon the basis of this determination. Clinical evaluation can often be notoriously inaccurate. The background and details of current therapy bave been outlined in working papers WPB/Cho1era/8 and WPB/ Cho1era/ll.
6.1.4
Use of adjuncts
It bas been established by :pathophysiologic studies tbat there is no therapeutic benefit in the use of antibiotics, sulfonamides, vasopressor agents, vitamins or parenteral glucose solutions. 6.2 6.2.1 Discussion Mainstay of therapy
There was agreement that there is no clinical difference between cholera El Tor and cholera Asiatica and that the mainstay of therapy is the rapid intravenous replacement of saline and the correction of acidosis as outlined. 6.2.2 Adjuncts
Several partici:pants reported experiences with the use of antibiotics both parenterally and orally •. Vasopressor agents, vitamin preparatiOns, morphine and adrenosteroid compounds were used by some workers. It was accepted that practically all adjuncts to therapy with saline, bicarbonate and potassium were founded upon individual clinical interpretation rather than upon pathopQysiologic considerations of the disease process. . Glucose as a parenteral fluid has been used by many clinicians during the recent epidemics. The Adviser stated that this is not a suitable replacement solution since glucose obligates the kidneys to eliminate sugar. The anuria which is the patient t s response to his deQydration is thus reversed so that ev;:.cn additional water and essential electrolytes are eliminated. 6.2.3 Oral treatment and subcutaneous administration
Tbe value of oral treatment and the efficacy of subcutaneous fluid administration especially in children were discussed. It was proposed that in view of present knowledge these methods could not be recaumended but that clinical evaluation was definitely indicated to determine their efficacy.
-206.2.4 Treatment under field conditions
Considerable emphasis was placed upon the need for adequate Various methods used in particular environmental situations were presented. This has been an especial.ly acute problem in sparsely populated rural areas. The usefulness of the copper sulfate method for determining the state of deb;ydra.tion under these circumstances 'to-as questioned. The ease, simplicity and effectiveness of the method was again stressed. Recommendations for general usage of this method were acceptable. and quickly mobilized field units. The limited use of plastic bags for parenteral solutions was presented by one participant. They are light and easily bandled and were found most satisfactory for field units. Participants were enthusiastic over the possibility of making these containers more generally ava1la.ble and exPressed interest in receiving further details on an informal basis.
6.2.5
stockpiling of supplies T
The need for adequate stockpiling solutions was emphasized an:! an amount of about 10 litres for each predicted case was suggested. The difficulties in obtaining parenteral supplies were noted and a number of ingenious and effective, if less than ideal, solutions of the problem were discussed. It was accepted that intravenous fluid should be administered as rapidly as possible in the most satisfactory form available, even if this be by necessity rainwater and salt in makeshift containers.
6.3 6.3.1 6.3.2
Conclusions There is no clinical difference between cholera Asiatica and cholera El Tor. Accordingly, the treatment is the same. There should be no death frem cholera in an unccmplicated patient with prcmpt and adequate therapy. Patients should be treated with intravenous saline and bicarbonate in a ratio of 3.:1 with potassium supplements as indicated. The treatment is a supportive measure for a selflimiting disease. The copper sulfate method fer determining plasma protein concentration is the best guide for dete~ining the state of deb;ydra.tion. It is as impOrtant and applicable in rural areas as in urban communities. stockpUing of the indicated solutions and few supplies necessary for field units should be undertaken upon threat of an epidemic. A suggested amount of fluid would be 10 litres for each prospective patient.
6.3.3
6.3.4
6.3.5
-21-
.-
6.3.6 6.3.7
The availability of plastic bags as an alternative container for solutions was suggested as worthy of more general usage. There has been a widespread use of antibiotics, sulfonamides, vasopressor agents, vitamins and parenteral glucose. There is no indication for these adjuncts. Their usage both canplicates the management and adds to the financial burden of an epidemic. The smple regimen of isotoniC saline and 2$ sodium bicarbonate has had an equal, if not lower, over-all mortali ty rate. There is need for clinical evaluation of the efficacy of oral treatment and supplements in the management of the cholera patient.
6.3.8
7. 7.1 7.1.1
RESEARCH
Presentation of further research needed Detection of cholera vibrios
This session was inaugurated by the Chairman and by two Advisers who observed that many methods have been recamnended for the collection, shipment and primary isolation of cholera organisms. However, not much canparative work has been performed in the field and the presumed relative efficiency of the different procedures is based on laboratory tests with pure or mixed cultures as well as with artificially infected stools. While many authors 4 have insisted that stool specimens are the only effective means to detect cholera vibrios in numerous cases after the first day of the disease and in carriers shedding only a few organisms, the rectal swab has become increasingly more popular. Parallel field evaluation tests are indicated. Bacterial variations and mutatiOns, including the deve10pnent of rougbness and their relationship to disease and epidemiology, are of paramount importance. Changes in the organisms have to be detected early when the cultures are fresh and such studies have to be undertaken with utmost speed, immediately after the vibrios are isolated in the field or in primary supporting laboratories. Phage typing has found its place in the d.ia.gn06tic armamentarium. While it is generally believed that phage types are constant, early testing may prove that this assumption is a fallacy; thus work sbould be performed also in this direction.
4pollitzer, R.
Ibid.
-22-
7.1.2
Evaluation of immunity status
There is the problem of tests for the evaluation of the status of 1D1Pun1ty. It is not certain that the determination of agglutinating antibodies alone will reveal the entire picture. Bacteriolytic and bacteriostatic tests have been used in the past with inconclusive results. Mouse-protection test experiments require extensive laboratory facilities with much need for personnel and animals. The recently developed techniques for the determination of antibodies, with the aid of agar gel diffusion methods, are pranising and feasible for field use and it is believed that they may be applied in conjunction with agglutination or other experiments. It is natural that only the examination of paired sera can give statistically significant results. The importance of evaluating vaccine trials cannot be over-emphasized.
The examination of water and food for vibrios has been carried out in different laboratories by diverse methods. It should be emphasized that it is necessary to develop a standard technique which is feasible for field use and which will give canparable results in the bands of various workers.
T
7.1.4
Role of insects
Filth flies, cockroaches and other insects have been implicated in carrying cholera vibrios in many instances. It has been found, however, as in Bangkok in 1958 to 1960, that flies may be very scarce in cholera-infected areas but numerous in districts free from this infection. Much of the work with inSects as carriers of enteropathogenic organisms was done under laboratory conditions. Again, field investigations could. furnish an answer.
7.1.5
standard sera and. reagents
The need for standard sera and reagents has been discussed previously. It is evident that such laboratory diagnostica have to be tested for their stability, efficacy and time of deterioration under field conditions.
7.1.6
Sources of infection
Since the knowledge of carriers and. their epidemiologic status is far from satisfactory, as much effort as possible should. be devoted to their study. In add1tion, a 'watch-dog l activity is reccmuend.ed. This should. consist of a periodic, for example weekly, examination of selected water sources on a year-in-year-out baSis, as well as a search for human carriers and. repeated testing of food samples for cholera vibrios. Such sampling, if carried out thorougbly and systematically, may yield results that have great :Importance not only during epidemics but also in une.tt'ected areas where the first appearance of cholera vibrios in water or man will serve as an alarm s1.gna.l.
II
- 23 -
7.1.7
Health education methods
Social sciences are important in the evaluation and estimation of the value of preventive and other public health measures. Their methods permit the establisbment of the level ~_educa.tion in the population. This educational level has to be estimated-not only from the grade of formal. schooling attended but also from reap,ing habits, patterns Of J.ifltening to radio and television, social preferences, participation in community aria other activities. The susceptibility to public health education and preference to certain means of !communication such as posters, handbills, loudspeakers, lectures, ,cartoons, newspapers and radio as well as attitudes towards diseases, will greatly facilitate the application of proper and effective public health educational methods. The problem of nutrition and its relations to cholera falls under this heading. Much research is desirable along these lines. The application of ingenious methods devised in public health education, vaccination, treatment and other fields was emphasized and an appeal made that such methods should be given wide publiCity so that they can be used in other areas.
7.1.8
Areas of electrolyte depletion
It was pointed out that while the qualitative and quantitative electrolyte losses in cholera have now been well delineated, the precise areas of depletion are not known. Recent research by the United states Naval Medical Research Unit No. 2 and the United states Radiological Defence Laboratory in the hydrated and dehydrated patient, using careful balance studies with radio-isotopes to determine the content of water and electrolyte shifts between cellular and extracellular spaces, was reviewed. Final analyses are still being determined.
7.1.9
Mechanism of diarrhoea
The mechanism of the diarrhoea in cholera continues to be of interest. The denudation of the intestinal mucosa as a theory has been unequivocally repudiated. The work of Phillips and Huber with the "sodium pumP'" inhibition due to the vibrio or its metabolic products as a rational explanation was reported. The mechanism of the "sodium pump" and the findings of both inhibitor and, recently, enhancer substances 1ri the plasma. and stool water of patients with cholera Asiatica and cholera El Tor were elaborated. It is felt that the inhibitor is definitely not an endotoxin but its identity remains to be determined. This b;ypothesis concurs with the clinical understanding of a ~-limiting disease and also possibly with the apparent vulnerability of certain 'Individuals susceptible to the vibrio. Research in this field would appear to be most fruitful.
7.1.10, Exper:lmental animal a ~
A suitabl.e experimental anima1 for investigation is pract1caJ.:ly gua. !l!2!! to determine the meche.ni SUI of cholera and to study
- 24 experimentally the effects of deQydration, shock and electrolyte losses. SUccess in this field bas been limited and further work is indicated.
7.1.11 Role of nutrition The fact tbat cholera is only seen in the lower socioeconanic groups was reiterated. The work in Bangkok, with intestinal biopsy specimens tbat revealed mucosal alterations suggestive of a malabsorptive state, both in the acute and one-year conva1escent patient, was noted. There is also evidence of :imp61red absorption of d-xylose in many of these patients. The status of nutrition and its influence upon the susceptibility to cholera and upon the pathogenesis and prognosis should be evaluated.
i
7.1.12 Oral regimen An effective and simple therapy has been developed for the treatment of the cholera patient. Frequently parenteral medication and fluids are difficult to obtain and oral treatment bas been attempted although its feasibility was doubted. If' a ss;tisfactory oral regimen could supplement or, less likely, replace the presently reccmnended parenteral tberapy, a great financial and therapeutic benefit woul.d be realized. Furthennore, oral therapy would constitute a definite convenience to both patient and physician and it would be especially important since the disease frequently occurs in inaccessible areas. The efficacy of treatment with solutions of different toniCity, varying amounts and differing schedules shoul.d be evaluated.
7.2 7.2.1
Discussiop Vaccine evaluation project, Philippines
During the ensuing discussions, the plans for the vaccine evaluation project in the Philippines were outlined. Among the points stressed was the selection of an adequately large population about 100 000 to 200 000 " where the disease may be expected within six months after vaccination. This population must be, of course, willing to accept routine immunization and once vaccinated, must be individually identifiable. On the basis of the experience with the disease, the lower socio~conanic groups are preferred for inrmm1zation. Two or three formulations of Cholera vaccines are to be used with typhoid vaccine suggested as a control. The double-blind technique in the giVing of specific vaccines is almost a ~ qua !!Q!l. Appraisal of vaccine efficacy may be accomplished prinCipally by the comparison of the attack rates in the various immunization groups. Ethical consideration in the witbholding of the vaccine 111 the control group may be resolved by the proVision and assurance of prompt and effective treatment.
7.2.2
Nutrition study, Philippines
A staff member of the Institute of Nutrition in Manila commented on the relationship between cholera and nutritional babits.· The Bicol peninsula, which bas been free fran cholera, has a
- 25 popuJ.a.tion which bas a better than average intake of proteins, vitamins A and C. The educationaJ.. status of the people on Bicol is also higher than on other islands of the Philippines. While 2i of the family income is spent on education on the average elsewhere, in Bicol this figure is 4.$.
7.2.3
Epidemiological studies needed
A participant from Malaya reccmnended the follow-up of carriers, the study of animals as possible hosts of cholera vibrios, and the relationship of microbial strains to clinical disease and epidemiology. He was supported by a speaker from Ja.pan who caamented on antigenic mutations and variations. The participants from Sarawak, North Borneo and Netherlands New Guinea stressed the need for further enquiries into carrier state and the behaviour of the cholera vibrios. This was supported by the Che.irma.n who referred to the apparently successful treatment of contact carriers with streptomycin during the outbreak in Hong Kong. Other antibiotics were also effective but were more expensive and there was always a small but definite risk of haematogenous crises developing. In the past certain work had been carried out using other therapeutic substances for the treatment of bealtby contact carriers. 5 It might be profitable to review this work, particularly in connection with the use of lactic acid preparations.
.L
Mention was also made of gall bladder carriers and the possibility of a true carrier state occurring in cholera. It was agreed the.t there was an urgent need for research into the problem of the contact carrier with attention being given to drug resistance developing during propbyla.xis and the variations in strain che.racteristics which may result. The participant from China. (Ta.iwan) referred to the difficulties in the choice of strains for vaccine preparation and emphasized the.t El Tor vibrios from the present epidemics have a tendency to became rough. Some of them carry a phage. He pointed out the difficulties experienced 1n the detection of cholera vibrios as well as in their nomenclature. One participant, fran Thailand, seconded him in his concern about nomenclature.
7.2.4
Activities of research laboratories
An observer from the Dacca SEATO Cholera Laboratory described the plans .and activities of the.t establisllment. Household case studies with neighbouring households serving as controls, will be stressed. Water and food examinations also will be carried out.
5Pollitzer, R.
Ibid • pp. 916.£022 . / .
- 26 A method for collecting and shipping rectal swabs with an early warniDg system . bad been worked out. False alarms did occur in the past and are expected to be experienced also in the future. NAG II vibrios vere found in one, and Providencia in a second, outbreak. Both inhibited the "sodium pump". Further dinical studies are scheduled also in Dacca. The Adviser fran the United states Naval. Medical Research Unit in Taipei pointed out that his unit is willing and able to participate in cholera research, especially in clinical and physiological work, on three days' notice. This offer was appreciated especially by the Ma.l.a.ya. and Singapore participants. Answering a question by one of the participants fram the Philippines, the Adviser whose base is in Tba.1la.nd, assured the meetiDg tbat the SEATO Medical Research laboratory in Bangkok is williDg and ready to assist in laboratory problems, especially in 1mmunologic questions, i f materials are subnitted.
7.3 7.3.1
Conclusions There is need to determine the relative efficacy of the bacteriologic examination of rectal swabs and stool specimens. This is especially jmportant in specimens obtained fran patients late during the disease and frem carriers. Pbage-typing methods feasible for field use should be developed further. Immunologic tests on paired sera fran naturally infected and fran vaccinated persons should be carried out on a larger scale. Data should be collected which may aid in the establisbment of standard methods for food and water examination. The role of filth flies and other insects in the effective transmission of cholera under natural environmental coDdit1ons requires further elucidation. There is a need for standardized laboratory reagents, including diagnostic sera. Available materials should be tested under field conditions for efficacy, ttme of expiration and deterioration. Vaccine tr1a.ls in selected groups using the double-blind technique and adequate controls should be set up. It is believed that ethical considerations arising in the control group can be met. A systematic periodic search for enteropathogenic vibrios in man, water and food should be carried out on a year-round basis in the entire area both as a check on the course of the present epidemic and as an alarm signal. if and when new areas are invaded by cholera vibrios.
7.3.2
7.3.3 7.3.4
7.3.5 7.3.6
7.3.7
7.3.8
-277.3.9 Studies by social scientists of the media applicable to local conditions are desirable. In this connection studies of the measurement of the formal and post-school educational status of the population, with regard to susceptibility to public health indoctrination and to methods used during such activities i6 indicated. The
7.3.10
status of nutrition and its influence upon susceptibility to cholera and the pathogenesis as well as the prognosis of the disease should be evaluated.
7.3.11 The role of the carriers, the duration of the carrier state after or without clinically manifest cholera, as well as the possible ~rtance of the gall bladder and the biliary system as a reservoir, should be examined.
7.3.12
The
efficacy of varying regimen proposed for the treatment of the carrier should be evaluated.
7.3.13 Further research should be continued to elucidate the mechanism of diarrhoea. The bypothesis of a "sodium pump" inhibitor 1s presently receiving wide attention and should be pursued.
7.3.14
The efficacy of oral treatment as either a replacement or, more p06sibly, a supplement to the present therapeutic regimen must be evaluated for both clinical and administrative benefits.
7.3.15 The need for a susceptible laboratory animal to help to determine the mechanism of cholera and generally study the effects of dehydration, shock and electrolyte losses, was supported.
7.3.16 Supporting and co-operating research laboratories are desirable. Research establishments in Dacca, Bangkok and Taipei signified their willingness to help those requesting their services, within their means and respective missions.
B.
INTER-COONTRY CO-oRDINATION
B.l
Notification of occurrence
Following the introductory remarks by the Chairman, the meeting noted with interest that the Scientific Group on Cholera Research bad. recamnended tba.t El Tor infection should be regarded as essentially identical with classical cholera and dealt with as such. It was confidently expected tba.t in the near future 'enteritis choleriformis El Tor' would be included in the definition of cholera and thus becane subject to the International Sanitary Regulations.
- 28 Thereafter, dissemination of in1'ormation on cholera El Tor woul.d follow the system maintained by WHO in respect of the six quarantinable diseases. It was emphasized that the notification of the occurrence of cholera El Tor was the responsibility of the health authority of the country affected and that it could be made on the basis of a reasonable clinical diagnosis which shall be confirmed as soon as possible by laboratory methods. 8.2 Extent of infected local area
In view of the insidious nature of the spread of cholera, the opinion was expressed that health administrations should give careful consideration to the size of the area declared as an "infected local area II. Direct transit areas could be specifically excluded in defining infected local areas but there was a real danger in permitting passengers to leave an airport, which was within an infected local area, without cempJ.y1ng with the accepted quarantine requirements. Provided that all travel agencies were kept ful.ly informed of any quarantine requirements notified to WHO by the health administration concerned, it was probable that all intending passengers would be well aware of these requirements. It was noted that in Hong Kong travellers making a temporary stay in transit frem areas infected with cholera El Tor, but which had not been declared as being 60 infected, were given a printed card indicating where a. diagnostic and treatment service was a.vailable in the event of symptoms occurring which were suspiCious of cholera.
8.,
Dissemination of information
Concern was expressed at delays in receiving information regarding outbreaks of quarantinable diseases in the Region and information sought as to whether or not WHO would consider re-opening the Singapore Epidemiological Intelligence Station. In discussion it was agreed that there were financial and administrative objections to this which were of considerable weight, but that alternative arrangements might be possible during the emergency situation created by the presence of El Tor infection in several countries in South-East Asia.
In this connection and in respect of the dissemination of in1'ormation on methods of control employed and other matters not within the scope of the epidemiological intelligence functions of WHO, attention was drawn to Article 104 of the International Sanitary Regulations. This article provides for special arrangements to be concluded between states having certain interests in common which are pertinent to the present circumstances of the prevalence of El Tor infections in the geographical areas represented at the meeting. It was agreed that assistance with the drafting of inter-country agreements should be sought fran WHO on the understanding that any agreements made were the subject of direct negotiation between the countries concerned. It was understood that WHO is prepared to give countries any advice or a.ssistance on developing arrangements under Article 104 of the International Sanitary Regulations.
-~ .. 8.4 Notification of freedom fram infection Advice was sought on the accepted quarantine period applying to cholezaEl Tor and it was confirmed that it is five days, the same as for classical cholera. The Chief Medical Officer, International Quarantine, WHO Headquarters, asked that before health authorities notified local areas as being free fram infection with cholera, consideration should be given to waiting for a period longer than twice the incubation period. One of the features of the epidemics which bad occurreJ. during the past twelve months was the reappearance of cases after a lapse of time well in excess of twice the incubation period.
8.5
Restriction on foodstuffs and commodities Attention was drawn to the wide range of restrictions imposed
by certain health administrations within the region on foodstuffs and other commodities exported from countries infected with chOlera
El Tor. While much work requires to be done to identify vehicles of infection and to determine the persistence and survival of cholera vibrios, it was agreed that the spirit and intention of Article 68 of the International Sanitary Regulations should be the basis on which restrictions are determined. Additional requirements or safeguards could be the subject of inter-country agreements under Article 104. In this cODIlection, note was taken of the suggestion that an infected country should ensure that foodstuffs and other commodities to be exported were free of cholera infection and that thereafter the health authority concerned could issue a certificate accordingly which would be acceptable to the receiving country.
8.6
Traffic not amenable to quarantine
Finally it was agreed that the problem of infection conve~~ by inter-island or coastal traffic in small vessels which were not amenable to quarantine restrictions should be given consideration when inter-country agreements were being negotiated. 8.7 8.7.1 Conclusions The recommendation of the Scientific Group on Cholera Research that El Tor infections should be regarded as essentially identical with classical cholera and dealt with as such was fully supported. The
8.7.2
system of notification and dissemination of information as provided under the International Sanitary Regulations and practised by WHO will provide adequate means for the rapid interchange of information.
8.7.3
Realizing that the health administration of a country infected with cholera Asiatica or cholera El Tor is responsible for defining the extent of infected local areas I the insidious nature of the dissemination of cholera vibrios should be taken into account in defining these areas.
- 30 -
8.7.4
The meeting, recognizing the :Importance of the inter-country
dissemination and exchange of information, urges that, with the guidance and assistance of WHO, inter-country agreements should be concluded under Article 104 of the International Sanitary Regulations.
8.7.5
Restrictions on the import of foodstuffs and other commodities fran countries infected with cholera should be applied "r!tbin the spirit and intention of Article 68 of the International Sanitary Regulations. Certificates issued by health administrations to facilitate importation should be the subject of inter-country agreements under Article 104.
The Chairman, Advisers and Participants wish to express their gratitude to the Regional Director of the Western Pacific Regional Office and bis staff for the facilities and hospitality accorded during the meeting. The ma.tly courtesies extended by the Government" of the Republic of the Philippines, the Secretary of Health, Dr. Francisco Q. Duque, a.nd the officers of the Department of Health are gratei'ully acknowledged. In particular, we wish to" thank members of the Secreta.T1at for the detailed administrative arrangements made for the meeting .and for the drafting of the report afterwards.
- 31 ANNEX 1 PROVISIONAL AGENDA 1. 2. ADDRESS BY DR. I. C. FANG, REGIONAL DIRECTOR ADDRESS BY DR. D.J.M. MacKENZIE, DIRECTOR OF THE MEErING AI>OPrION OF THE AGENDA
3.
4.
DIAGNOSIS OF EL TOR VIBRIO PARACHOLERA Discussion on this topic to be opened by Dr. O. Fe1senfeld
5.
PRESENTATION OF HIGHLIGHTS ON THE RECENT OUTBREAKS IN SARAWAK, HONG KONG, MACAO, PHILIPPllJES, NORTH BOHNEO AND SOOTB-EAST ASIA EPIDEMIOIOOY OF EL TOR VIBRIO PARACHOLERA Discussion on this topic to be opened by Drs. O. Fe1senfeld
6.
and J.J. Dizon
7.
PREVENTION AND CONTROL OF PARACHOLERA (mruNIZATION) Discussion to be opened by Dr. D.J.M. MacKenzie
8.
PREVENTION AND CONTROL OF PARACHOLERA (SANITARY AND 0l'HER MEASURES) Discussion on this topic to be opened by Dr. D.J.M. MacKenzie
9.
TREA'lMENT OF PARACHOLERA PATIENTS Discussion to be opened by Dr. C. Wallace
10.
RESEARCH ASPOOTS OF PARACHOLERA Discussion to be opened by Drs.
o.
Fe1senfeld and C. Wallace
11.
DISCUSSION ON INl'ER-C00l'lTRY CO-DRDINATION, WITH PARTICULAR EMPHASIS ON THE DISSEMINATION OF INFORMATION REGARDING THE ONSET OF aJTBREAKS AND MEASURES TAKEN TO COl'frROL THEM Discussion to be opened by Dr. D.J.M. MacKenzie
12. 13.
SUMMARIZA1'ION OF DISCUSSIONS AN'! OTHER BUSINESS CIOOING REMARKS BY DR. I. C. FANG, REGIONAL DIRECTOR
14.
",
"
't
.,.
~
.... ANNEX 2
PROVISIONAL SCHEDULE CF EL TOR loEETING
April 1962
16 April 9:00 a.m.
MONDAY
TUESDAY 17 April
WDNESDAY 18 April
THURSDAY 19 April
:Address by Dr. I.C. Fang :Prevention and Control of :Tree.tment of Paracbolera :Co-ordination between :Paracholera (Immunization) : Patients :Governments :Discussion to be opened by :Discussion to be opened by:Discussion to be opened :Address by Dr. D.J.M. MlcKenzie Dr. r.i1.cKenzie Dr. Wallace Dr. *cKenzie :Coffee break :Diagnosis of El TOr : Pa.racholera :Discussion to be opened : by Dr. Felsenfeld :E;Pidem101ogy of El Tor :Paracbolere. :Discussion to be opened by Drs. Felsenfeld and : Dizon : Coffee break :Discussion : Coffee break :Discussion . Coffee break : Discussion :eoffee break :5ummarization of Discus;sion5 :Dr. MacKenzie and Advisers
10:00 a.m.
10:15 a.m.
to 11:50 a.m. :~
2:00 p.m.
:Prevention and Control of :Research Aspects :Further discussion on :Paracholere. (Sanitary and :Discuss10n to be opened by:finished and unfinished Drs. Felsenfeld and :business :Other lobasures ) :Discussion to be opened by Wallace : Dr. t.bcKenzie : Coffee break :Discussion :Coffee break :Discussion : Coffee break . : Closing Remarks by Dr. I.C. Fang
3:00 p.m. 3:15 p.m.
to 5:00 p.m.
- 33 -
LIST OF PARTICIPAlfl'S 1.
Participants Western Pacific Region . CHINA (TAIWAN)
Dr. C.H. Yen Department of Health Taiwan Provincial Govermnent Wuf'engHsiang Taichung, Taiwan
. HONG KONG
Dr. D.J.M. MacKenzie Director of Medical and Health Services Medical and Health Department Tower Court, Hysan Avenue Hong Kong Dr. Shoichi Iwata
JAPAN
Chief, Quarantine Section Public Health Bureau Ministry of Health and Welfare Japanese Government 1-2 Chane, Kasumigaseki Chiyoda-ku Tokyo
*Dr. Hideo Fukumi Chief Department of Bacteriology I National Institute of Health Tokyo KOREA Dr. Yu Un Soung Director of the National Seoul Airport Quarantine Station Ministry of Health and Social Affairs Seoul Dr. J. Paiva de Martins Chief Health Services Macao Dr. L.S. Sodby
MACAO
MALAYA
Municipal Health Officer c/o Ministry of Health and Social Welfare Federal House KUala Lumpur
*Attendance at their respective Government's expense.
- 34 -
*Dr.
L.W. Jayesuria Deputy Director of Medical Services Ministry of Health and Social Welfare Federal House Kuala lumpur Dr. O. KranendoDk Deputy Director Department of Public Health Ho1la.ndia
NORTH BORNEO
Dr. A. Szeley c/o Medical De];lartm.ent Jesselton Dr. Jesus Azurin Director Bureau of Quarantine Manila
*Dr. T.P. Pesigan Director Bureau of Research and Laboratories Philippine Department of Health Manila
•
*Dr. Amadeo
H. Cruz
Director Bureau of Health Services Philippine Department of Health Manila
RlUKYU ISLANDS
Dr. Chokei Ogimi c/o The Director of Public Health and Welfare Public Health and Welfare Department United States Civil Administration of the Ryukyu Islands
APO 331 San FranCisco, California
SARAWAK
Dr. M.A. Rozalla AsSistant Director of Medical Services (Health) Medical and Health Department Kuching Dr. Ng See Yook Permanent Secretary (Health)/ Director of Medical Services Singapore
SmGAPORE
*Attendance at their respective Goverment's expense.
- 35 ANNEX 3 VIET-NJIM
Dr. Truong Van Quynh
c/o The Secretary of State for Health Saigon South-East Asia Region DIDONESIA
Dr. R.E.M. Sul.ing Director of the Division of Epidemiology and Quarantine Ministry of Health Djakarta Dr. Cba.mlong Harina.suta Dean, Faculty of Tropical Medicine University of Medical Sciences Bangkok *Dr. Doom Bunnag
THAILAND
Medical Sciences Department Ministry of Public Health Bangkok •
Eastern Mediterranean Region PAKISTAN Dr. Mohammed Ataur Rahman
Superintendent East Pakistan Vaccine Laboratory Institute of Public Health Naha.kaJ.i Tejgaon PO Dacca 2.
Observers Dr. Uoyd Florio Chief Public Health Division AID/USOM Manila, Philippines
Colonel John Rizzolo Area SUrgeon United States Air Force Clark Air Force Base Angeles, Pampanga Philippines Dr. George W. Beran Director of Research Sill~ University Mission Hospital Dumaguete City· Philippines
- 36 ANNEX 3 Dr. J. L. Stockard Pakistan~
...
Deputy Director and Epidemiologist Cho1era Research Laboratory Dacca, East Pakistan Lt. CoJ.one1 Samue1 C. Gallup Preventive Medicine Officer United states Army Ryukyu Islands Lt. Colonel Roy A. Highsmith Director Public Health and Welfare Office of the High Commissioner Ryukyu Islands Dr. Hiroshi Ogonuki Member, Central Pharmaceutical Council Tokyo, Japan Dr. Victor C. Valenzuela Acting Dean Institute of Hygiene University of the Philippines Manila, Philippines Dr. Potenciano R. Aragon Professor and Head of the Department of Medical Microbiology Institute of Hygiene University of the Philippines Man11a, Philippines r--
Dr. Generoso B. RaDan Assistant Professor Department of Epidemiology and Public Health Administration InstItute of Hygiene University of the Philippines Manila, Philippines ~
, I
II II I I
Dr. Alfred Evans WHO Consultant on laboratory Management and Administration in the PhUippines WHO/WPRO Man11a, PhUlppines Dr. J. Bulatao-Jayme Institute of NUtrition Man11a, PhIlippines ....
- 37 ANNEX: 3
Dr. Jose V. PlantiJ.J.a, Jr. Medical Specialist I (Microbiology and Pathology) Bureau of Research and Laboratories Philippine Department of Health Manila, Philippines Dr. Guillermo SD. Justiniano Medical Specialist II (Epidemiology) Bureau of Health Services Philippine Department of Health Manila, Philippines
Mrs. CecUia Z. Ganez Research Bacteriologist Bureau Of Research and Laboratories PhUippine Department of Health ManUa, PhUippines Dr. V. Basace.-Sevilla
Chief Research Bacteriologist Bureau of Research and Laboratories Philippine Department of Health Manila, PhUippines Lt. Commander J. William Cox, MC Chief of Medicine U.S. Naval Station Hospital U. S. Naval Base Subic Bay Philippines Dr. Rosaline. B. San Juan Supervising Epidemiologist and Chief of the Division of Epidemiology Disease Intelligence Center Philippine Department of Health Manila, Philippines
3.
AdVisers Dr. D.J .M. MacKenzie (Director of the Meeting) Director of Medical and Health Services Medical and Health Department Tower Court, Hysan Avenue Hong Kong
IIC
- 38 -
Dr. O. Fel.senfeld (Epidemiology) Director TJnited States Canponent S~O Medical Research Laboratory Bangkok, Thailand Dr. J. J. Dizon (Epidemiology) Director Disease Intelligence Center Philippine Department of Health Manila, Philippines CCI!!!!!!!.nder Craig K. Wallace, MC, USNR Clinical Investigator United States Naw.l Medical Research Unit No. 2 7-1 KUng Yuan In Taipei, Taiwan Republic of China (Clinical Mazlagement)
,
-
t
4.
Secretariat
Dr. R. I. Hood Chief, International Quarantine World Health Organization Geneva, Switzerland Dr. Chia-chi Me. (Secretary) Assistant Director of Health Services World Health Organization Regional Office for the Western Pacific Manila, PhilippiDes Dr. D. R. lilggins Regional Adviser on Camnmicable Diseases World Health Organization Regional Office for the Western Pacific Manila, Philippines Dr. D. Sovrlich WHO Epidemiologist Djakarta. IDdonesia "' II ,, ,,
, I
- 39 ANNEX 4 LIST OF DOCUMENTS
•
WPR/ Cho1era/ 1 WPR/ Cho1era/ 2 WPR/Cho1era/3 I )0
PROVISIONAL AGENDA LIST OF PARTICIPANTS, OBSERVERS AND TEMPORARY ADVISERS PARACHOLERA EL TOR IN THE PHILIPPINES, 1961-1962 EPIDEMIOLOGIC ASPECTS AN EPIDEMIOLOGICAL AND lMMUNOUlGICAL S'lUDY OF EL TOR· VIBRIO PARACHOLERA IN NEGROS ORIENTAL, PHILIPPINES REMARKS ON THE EPIDEMIOLOGY OF THE 1961-1962
WPR/ Cholera/4 WPR/ Cho1era/5 WPR/ Cho1era./ 6 WPR/ Cho1era/ 7 ~
EL TOR EPIDEMIC SOME CHARACTERISTICS OF THE EL TOR VIBRIOS ISOLA.'l'ED FRCM THE 1961-1962 EPIDEMIC ''PARACHOLERA EL TOR" 00TmlEAKS IN INDONESIA THE TREA'lKI'!NT OF CHOLERA CUTLINES OF PREVENTION 100) CONTROL PROGRAMME IN JAPAN AGAINST PARACHOLERA DUE TO EL TOR VIBRIOS, 1961-1962
,
I \
.
WPR/ Cho1era./ 8 WPR/ Cho1era/9 WPR/ Cho1era/10
1 , i
I I I _.J>,
SOME BIOLOGICAL 100) SEROLOGICAL CHARACTERISTICS OF '!'HE VIBRIO STRAINS FORWARDED TO US FRCM VARICUS PLACES IN SOUTH ASIA AS THE CAUSATIVE AGENT OF THE SO,-CALLED "PARACHOLERA" .ASPECTS OF CLINICAL MANAGEMENT OF PARACHOLERA . PATIENl'S A HEPORI' ON THE CHOLERA <lJTBREAK IN SARAWAK
WPR/ Cholera/ 11 Unnumbered Unnumbered Unnumbered
''EL TOR" CHOLERA IN THAILAND
REPORT ON CUTBREAKS OF EL TOR VIBRIO PARACHOLERA: 1962 NORTH BORNEO REF'ERENCE ON PARACHOLERA CHOLERA EPIDEMICS IN THE WORLD WRING THE LAST FEW YEARS (1955-1961)
Unnumbered Unnumbered
1 I , 1
I 1
I :. ,
I
WORLD HEALTH ORGANIZATION
ORGANISATION MONDIALE DE LA SANTI!i
REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
MDJ:ING FOR THE EXCHANGE OF ~ON ON EL TOR VIBRIO PARACHOLERA
WP8/ C'r.merall 2 Apr1l1962 ElIGLISB 0lILY
Manila, Ph1lippines
16-19 Apr1l 1962 PROVISIONAL AGENDA
1. 2.
ADmESS BY DR. I.C. FABG, REGICfiAL DIRECTOR ADmESS BY
m.
D.J.M. MacKENZIE, DIRECl'OR OF THE MEE'l!ING
ADOPl'ION OF THE AGENDA. 4. DIAGNOSIS OF EL TOR VIBRIO PARACHOLERA
Discussion on this topic to be opened by Dr. O. FelseDfeld 5. PRESENTATION OF BIGBLIGmS ON THE RJ!XEiT OOTBREAKS III SARAWAK,
BORG KONG, MACAO, PBILIPPIIES, NORTH
BOmfiX)
AND SCVl'B-EAS'l' ASIA
6.
EPImMIOIOOY OF EL TOR VIBRIO PARACHOLERA.
Discussion on this topic to be opened by Drs. O. Felsenteld and J.J. Dizon
Discussion to be opened by Dr. D.J.M. MacKenzie
8. .~
PREVmTION AND CONTROL OF PARACHOLERA (SANITARY AND
ormm MEASORES)
-· '-
Discussion on this topic to be opened by Dr. D.J.M. MacKenzie
9.
TREf..'lMENT OF PARACHOLERA PATIERTS
Discussion to be opened by Dr. C. Wallace 10. RESEARCH ASPECl'S OF PARACHOLERA
Discussion to be opened by Drs. O. Felsenfeld aad C. Wallace
WPF/166/62
. WPR/ CbJJ1era/ 1 Page
2
li.
DISCUSSION ON
INTER~OONTRY
CO-oRDINATION, WITH PARTICULAR l!MPHASIS
ON THE DISSEMINATION OF mFOBMATION REGARDING THE ONSE.'r OF OOTBREAKS AND MEASURES TAKEN TO CONTROL Tlm4
Discussion to be opened by Dr. D.J.M. MacKenzie
12. 13.
SUMMARIZATION OF DISCUSSIONS ANY arHER B]SINESS
14.
c:r.ooING REMARKS BY DR. I.C. FANG, REGIONAL DIRECTOR
.~.
PROVISlaw.. SCBJmJLE CP EL '.l'OO lotiE'l'ldG April 1962
I«lNDAY 16 April
TUESDAY 17 April
WEDNESDAY 18 April
THtlRSDAY 19 April
9:00 a.m.
:Address by Dr. I.C. Fang :Prevention and COntrol of :TreA.tmmt of Paracho1era :Co-ord1nat1on between :Paracho1era (Jmrmm1 zation) :Patients : GovernJllents :Address by Dr. D.J.M. :Discussion to be opened by :Discussion to be opened by:Discussion to be opened : MacKenzie : Dr. z.kcKende Dr. Wallace Dr. loiI.cKenzie : Coffee break :Dia.gnosis of El Tor : Paracholera :Discussion to be opened : by Dr. Fe1senfe1d :EPidemiology of E1 Tor : Paracholera :Discussion to be opened by Drs. Felsenfe1d and : Dizon : COffee break :Discussion : COffee break :Discussion :COffee break : Discussion :Coffee break :Summarization of Discus:sions :Dr. z.kcKenzie and Advisers
10:00 a.m. 10:15 a.m. to 1l:50 a.m.
2:00 p.m.
:Prevention and COntrol of :Research A§Pects :Further discussion on :Paracho1era (Sanitary and :Discussion to be opened by:finished and unfinished :Other M:!asures ) Drs. Felsenfeld and :business :Discussion to be opened by Wallace : Dr. lecKenzie : COffee break :Discussion : Coffee break :Discussion : COffee brealc . :C1osing Remarks by Dr. I. C. Fang
3:00 p.m. 3:15 p .. m. to 5:00 p.m.
, ( ( ',I
f
• ~
•
'--
'* ,
..,
( ( .Jj
:J
'"
•
• WORLD HEALTH ORGAN I ZATION ORGANISATION HONDIALE DE LA SANT~
REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAl DU PACIFIQUE OCCIDENTAL
MEm'mG FOR THE EXCHANGE OF INFORMATION ON EL TOR VIBRIO PARACHOLERA Manila, Philippines 16-19 April 1962
WPR/ CblJlere/ 2 ENGLISH ONLY
12 April 1962
LIST OF PARTICIPANTS, OBSERVERS AND Tl!H?ORARY ADVISERS PARTICIPAMS
WESTERN PACIFIC REGION CHINP. (TAIWAN)
'Dr. C.H. Yen Department of Health Taiwan Provincial. GoverIlDent Wufeng Hsiang Taichung. Taiwan Dr. D.J.M. MacKenzie Director of Medical and Health Services Medical and Health Department Tower Court, Hyse.n Avenue Hone; Kong Dr. Shoicbi Iwata Chief, Quarantine Section Public Health Bureau Ministry of Health and Welfare Je.panese Government 1-2 Chane, Kasumige.seki Chiyoda-ku
HONG KONG
\
Tokyo Dr. Hideo Fukumi Chief Department of Bacteriology I National Institute of Health Tokyo KOREA Dr. Yu Un Soung Director of the National Seoul Airport Quarantine Station Ministry of Health e.nd Social Affairs Seoul
.'-
liffi/198/62
•
•
WPR/ Cholera/ 2 Page 2 Dr. J. Paiva de Me.rtiI;ls
Chief Health Services Macao MALAYA
Dr. L.S. Sodby Municipal Health Officer c/o Ministry of Health and Social Welfare Federal House Kuala IAlmpur Dr. L.W. Jayesuria Deputy Director of Medical Services Ministry of Health and Social Welfare Federal House Ki.la.l.a IAlmpur
NETHEPLANDS
Dr. O. Kranendonk Deputy Director Department of Public Health Hollandia-Binnen Dr. A. Szeley
NORTH BORNEO
c/o Medical Department Jesselton PHILIPPINES Dr. Jesus Azurin Director Bureau of Quarantine Manila Dr. T.P. Pesige.n Director Bureau of Research and laboratories Philippine Department of Health Manila Dr. Amadeo H. Cruz Director Bureau of Health Services Philippine Department of Health Manila
RYUIaU ISLANDS
Dr. Chokei Ogimi c/o The Director of Public Health and Welfare Public Health and Welfare Department United States Civil Administration of the R;yuk;yu Islands APO 331
San Francisco. California
•
WPR/ Cholera! 2 Page 3 SARAWAK Dr. M.A. Rozalla Assistant Director of Medical Services (Health) Medical and Health Department Kuchine; Dr. Ng See Yook Permanent Secretary (Health)/ Director of Medical Services Singapore Dr. Truong Van Quynh c/o The Secretary of State for Health
Saigon
-... 1 ...
SOUTH~EAST
ASIA REGION
Dr. R.E.M. SuJ.ing
Director of the Division of Epidemiology and Quarantine Ministry of Health Djakart..l!; Dr. Chamlong Harinasuta Dean, FacuJ.ty of Tropical Medicirle University of Medical Sciences Bangkok
Dr. Doom D(.lD.OOg
Medical Sciences Department Ministry of Public Health ~~
EASTERN MEDITERRANEAN REGION
Dr. Mohammed Ataur RalJ:nan
Superintendent East Pakistan Vaccine Laboratory Institute of Public Health Nabakali Tejgaon PO Dacca
TEMPORARY ADVISERS Dr. D.J.M. MacKenzie Director of Medical and Health Services Meuical and Health Department Tower Court, Hysan Avenue Hong KOng
WPR/ Cho1era/ 2 Page 4
Dr. O. Fe1senfe1d Director United States Component Cholera Research Laboratory llangkok
COTI'4'l!8.DiI.er Craig K. Wallace, MC, US1iIR Clinical Investigator United States Naval Medical Research Unit No. 2
7 -1
Klmg Yuan
Taipei. Taiwan
:w
Dr. J.J. Dizon
Director Disease Intelligence Center Philippine Department of Health Manila
-.,/
OBSERVERS
Dr. Lloyd Florio Chief Public Health Division AID/USOM Manila
Colonel John Rizzolo Area Surgeon United States Air Force Clark Air Force llase Angeles, Pampanga Dr. Harry F. Colfer Medical Officer in Charge United States Public Health Service American Consulate General Hong Kong
Dr. George W. Beran Director of Research Sillfman University Mission Hospital Dumaguete City
WPR/ CbtJlera/ 2
.. Dr. J. L. Stockard Regional Director and Epidemiologist Pakistan-SENrO Cholera Research Laboratory racca, East Pakistan
Page
5
Lt. Col. Samuel C. Gallup Preventive Medicine Officer United States ArrrIy Ryukyu Isla.nds Lt. Col. Roy A. Highamith Director Public Health and Welfare Office of the High Commissioner R;yuk;yu Islands Dr. Hiroshi Ogonuki Member, Central Pharmaceutical Council Tokyo, Ja.pan Dr. Victor C. Valenzuela. Acting Dean Institute of Hygiene University of the Philippines Manila. Dr. Potenciano R. Aragon Professor and Head of the Department of Medical Microbiology Institute of flYgiene University of the Philippines Manila Dr. Generoso B. Roman Assistant Professor Department of Epidemiology and Public Health Administration Institute of HYgiene University of the Philippines Manila
WORLD HEALTH ORGANIZATION
ORGANISATION MONDIALE DE LA SANT~
REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
MEETING FOR THE ElCCHANGE OF INFORMATION ON EL TOR VIBRIO PARACHOLERA
WPR/ C'oolera/3 4 April 1962 ENGLISH ONLY
,
.....
Manila, Philippines 16-19 April 1962
PARACHOLERA EL TOR IN THE PHILIPPINES 1961 - 1962 EPIDEMIOLOGIC by ASPECTS
J. J. Dizon, M.D., M.P.H. Chlef Disease Intelligence Center Rosalina B. San Juan, M.D., M.P.H. SUpv. Epidemiologist, D.I.C. Julio P. Valera, M.D., M.P.H. Senior Epidemiologist, D.I.C. Manuel G. Alvero, M.D., M.P.H. Senior Epidemiologist, D.I.C.
I
"-
,
PARA CHOlER A EL TOR IN THE PHILIPPINES 1961-1962 - EPIDEHIOLOGIC .ASPECTS -
.... ,.........
I
FORE"TORD ••••••.••
................... " .. " ....... , , ., ..
1 2
II
INTRODUCTION ••• " •••• "."." •• "." •••••••• ". "." ••••••• " • •
'"
,
1. Recent Epidemics of Paracholera El Tor ••••••••• 2. Precuationary Measures Instituted •••••••••••••• III
2
4 5 16
PREVIOlli EXPERIENCE tIlTH CHOLERA IN THE PHILIPPINES 1. The Problem - Extent and Hagnitudes............. 1.1 Epidemic Curve ••••••••••••••.•••••• "....... 1.2 Pattern of Spread ••.••••• ,.t •••• t It " It It..
IV - THE PRESENT EPIDEMIC .......................... ".......
16 16 19
1.3 Horbidity and 110rtality Trends ............. 1.4 Case Fatality Ratios .• •.•••• ... • ... •• •• .• •• • 2. Localized Outbreaks - Epidemiological Feature •• 2.1 2.2 2.3 2.4 2. 5 2.6 l-Ianila •••••. ,. •••••.•••••••••••••• '". • • .. • • • • Ilocos Sur ••••••• " •••.•••••••••'••• '". • •• ... •• Calbiga (Samar) ••••••••••••••••••••••• ".... Lanao del Sur ••••••••••••••••••••••• , • • • • • • Sulu ..................... ZaI!lbOangR del Norte ........................ I • • .. .. • •. • • .. • .. • • ... • • I • • .. ..
24 28
35 35 40 42 43
45 46 47
2.7 National Mental Hospital- An Institutional.. Outbreak
3. Host Attributes ....................................... . 3.1 Age and Sex Dllitribution ••••••••••••••••••• 3.2 Occupational Incidence: Socia-Economic ••••• Groups and Nutritional Status 3.3 Inrrnunization Status ........... 4. Environmental Factors ............................ . 4.1 Geographical Distribution of Cases ••••••••• I •••••••••••••
53 53 59
60 62 62 62
4.2 J-1eteorological Fact0rs ....................... . 4.3 '::Jater Supply ....................................... .. 4.4 Food Supply ........................................ . 4.5 \·Jaste Disposal ..................................... .. 5. Transmission of the Disea~e ....................... . 5.1 Source of Infection .............................. .. 5.2 CR.rrier State ............................ " ... .. 5• .3 Vehicles of Transmission ......................... ..
67
65
6. Further Epidemiological Studies and Inveatigap. tions Indicated '-
72 76
69 71 71 80
....
V.SUM~1ARY
........................................... ..
B4
-000-
t
Nm1BER 1 •••• ~~ ••••••• Philippines, Cholera f10rbidity and Nortality, Number and R.c'lte (per 100,000 Pop.), 1906-1960 2 ,., •• '••~ ••.• , •• Philippines, P8.racholer'l El Tor: "., Reported Cases and Death by \rveek Epidemic P'ori0d, 1961-1962 3 " ., ,', Philippines, Reported Parach01cra It -, It • It . '• El Tor: Provinces and Cities by IJeek, 1961-1962 4 ..... ""4 ........ Manila,. Philippin8s, Parachulera El Tor Cases by Age, 1961-1962 5 , .............. Gitstro-Enteritis , Admissions by vJeeks, San Lazaro Hospital, Manila 19616 ............... Parach01c,ra El Tor Cases and Deaths ....... ,. Calbiga, Samar, Nr)v81'1ber 12-December 1, 1961 7 •••••••_ ........ Paracholera El T'J1': Cases by 3-Day • • • • •• • Period, Lanao d81 Sur, Nrwel'lber 29, 1961-January 4, 1962 8 ................ Pp.racholera El Tor: Cases by Resi- ....... denee Unit, Nati)nal Henta1 Hospit 2.1 , 1961-1962 9 ........ ~ .............Paracholera El Tor: Age Specific • • • •••• C'l.se and Death Rates (per 100,000 population), Henila Area, 1961-62 10-A .......... , •.•.Par'l.chnlera El Tor: Cases by Age ••••••• Several Areas, Philippines, 19611962 10-E ........... P".rCtcholera El Tor: Cases by Age Per Cent Distribution, Sev,-,ral Areas, Philippim,s, 1961-1962 11 ••.••••••••• , .Paracho18ra El T')r: Age SpeCific Case, FatRlity Hatios, Hanila and Capiz, 1961-1962 12 ............. Paracholera El Tor: Cases by Sex, Manila Area and Capiz, 1961-1962 13 .•••••••..•••• Paracholera El Tor: Cases as to l',fater Supply, Hanila and Suburbs, 1961-1962 If • • • • • 14 ••••.•••••• , • Philippines , Parachclcra El Tor: Cases by Food ItoQs, 1961-1962 "
·..... ... .... ... -
~
11 17 29-34 38 39 42 43 52 53 56 56 58 58 66 68
....
04.0 ••••
."""
....... It • • • • •
•
............
........
·...... ·.......
...
Nill1BER
I-A I-B
-
l-C 2
Cholera, Geogrnphical ·........ Philippines, Distribution, Rate per 1,000 pop. 1919 Epidemic Cholera, Geographical ·. ...... . Philippines, Distribution, Rate per 1,000 pop. 1930 Epidemic Pnracholera El Tor: ·........ . Philippines, Distribution Rates " ., Geogr~phical
.EMili ••••• ..... 12 13
14
3
4
5 (,
Hajor Cholera Epidemics ••••. ·........ . Philippines, Since 1919, Cases by Month Paracholera El Tor: ·." ...... . Philippines, ·"... Reported Cases by l.1eeks, Epidemic Period, 1961-1962 El Tor: Geogritphical ·........ . Paracholera Distribution of Cases, Manila Area, 1961-1962 ·........ . Philippines, Paritcholera El Tor: ·.... Cases by Week and Region, 19611962 Paracholera El Tor: ·........ . Philippines, ·.... Major Localized Epidemic Sites,
per 1,000 pop. , 1961-1962
15 18 21
25
7 8
·........ . ·........ . ·........ . ·........ .
.... 9 10 11
·........ . ·........ .
12
1961-1962 Paracholera El Tor: Distribution of Initial Cases, Manila, 19611962 National Mental Hospital, Para" cholera El Tor Cases, by Dates of Onset, November l8-Dec. 1, 1961 National Nental Hospital, Paracholera El Tor, Cases by l-Jeeks 1961-1962 Paracholera El Tor: Age SpeCific Cf'se Rates per 100,OCO pop. K,nila Aren, 1961-1962 Paracholera El Tor: Age Specific Death Rates, per 100,000 pop. M~nila Area, 1961-1962 Philippines, Paracholera El Tor: • •••• Infected Areas, 1961-1962
·....
37
.... ·..... ·.... ·....
49 54
55
Tllis paper io e pxeoenta-vion of oboervations disease - Paracho1era ill ~or
i1l~de
on tho
- as it occurred ill the Philippines to
du::dn:::; the Y<ilE:.:::o 1961 a:ld 19:52, particule:dy ..ritIl reference
its opideciiological aspects. on "(;~e
It includes specific observations of cort&in localized outbreaks of
oiJicle::llolot;ic
~~..itt.-.::cs
ooorl;.ina-l;ioll of the varioCls aGe::lcies of tnc DGpe..rt;;:.oct of lie&l t~,
pa.:::ticalsrly 1&::l00
t~ose
i1:: -the field. -(;n0
ThrouGh t:'1G vigilant ourTeil...; rcco.;ni tion a.nd verifi catio:.:1 of
:.:eo",-a::2is;:! inoti-l;uicci, t~ey
caseD co
occurred,
t~e
notification inplebented throuGll the
a.Dd outbl.... c~o
..;"1. . .
tae
fieli, t'ie Disenoe IntelliGence CC:lter of the Depark:ent
of u..l.-"
.
~, \.
rcct
epiclc~iolo3ic
oboervationo on tho discaoo.
INTRODUCTION ~~olera ~ad be~
&boent in tao Philippineo for about 25 therefare, of epideoico of cholera du~
yearo.
The
a~pear~nce,
to the El Tor vibrio Aeio. :l~icll,
wit~
high
~ortality
in areen in
Eeotcrn oici-
tlith t<:ic exception of the Celebeo, had been t~e dise~no
lerly iroe of
for
abo~t
the nawe period
of
tioo
ao it.;:) Pnilippinco, cros.tod qui-::'e c:n appronenoiol1 ne to ito ponaiblo cpro&.il -::'0 thin cow:-1;ry, eapecially conoidcring the oen~G
pre-
of fQ.c~iio;:n that vlouli r':E:2tc Due!:. oprcad poociblo.
1. R.eo0nt Epidcr.1ic;:) of Parac::'olcre:. El 'Lor -
.In
1961,
rmrak, Ale.cao, pocaibly Southern Chine:. an;! ROl1GJ:l:ong. 0:;. July 14, 10tH, tDe 'iVorld lieG.1 t:'1 OrG;[:::!izodio;c, d.cclc..rcd
....
ire;;;. J-'::? 1 to July 3, 1261.
S~rsmc.k 02.;:)00
had :.1ot exporienced cl::.010reported.
rEi. oi:::co 19()2.
In 2.11, 27D
=d 61:1eetllo WGre
Cacoc -aoro princip!l.11y iil the 20-40 ye".r Q,£.;e Group. The.ini th,l rll.lCpao·i;, OG;:lGO
;)ccurrc·,:l a5..jc..con:t copra iror,: tilG
to"
a pier i.lJ'ncre
t.~.:..ore
were;
!.:100I'Gd
bo;:;to c..ra£~
,;)~in.:;in;:;
P:-.rac~oler~.
El To::- cr:decic Celcbeo
• ~E;.& e~ttc::!.ded tnrou3~
rolata to poroon:J "ilho t~ceo
the aragon. boat rOGcttn. Ino-
of :liz-act. o:)ro£:,ri
30ciel c..ffc..irG .:,w..:l e.:Jpociall~r
th::'oUC;b. funo::-<:.10 ~1lJ.crc friomic 2.!ld relatives dicplcyed gri of by hanCi ODd
"body .contact
VIi tii
tho corpoe "/oro recorded. The
fincl.
3 C~OG
wuo raportod on
Sap~oobor
18. reporto of Pnrncholera
Although denied
by tho CUineoG,
clu.ri~G Juno and July i:l K't'l£'lo:l(,;tu=..g Province ware roc~-ivcd tl:rough
indix~ot
courcoc.
Oval' 30,000 dC3tho were ruoorad.
-1;.
Dinor out-
brenk n oi Peraoaolerc. (Ell Tor otreill) wno a,hi tted by tuo C;;:.nton
re.aio. C2.GeG i::.1 Maoao· were iirat reported by a 3.eutol"O diopc:.tou
on ~u~uot 11.
On A~6UOt 14, 1961, tho World lienIth Or3~uization ~atVlaon.tho
deol2.rod Mcceo infccted., auG. G~Ci.
woako Very
o:=.da6. i;.;;'C;.:.ct 19 littl~
Sopicc:iJol." 23, 13 o,.,:Jeo ~!.:!J
~1Cro
rCForted.
io kllOl'r.:l
of
pc.:i,tcrn of
OC~llrrc:.J.CC
ox
caoca in thio epidemic. cc~oao
On J...u;;uot 15, lIH31, roporto of two m.l:lpect
of
01:.0-
:)uboo'l:lc:.:tly iocle.rod .2.1 GO i:!footod by tIle W'orl~ llC i;.-:' 1 tIl Orgc:.ni-
bro~~::"t
72 cc:.oo:J and 15 aco;:;uo ud occurro::;'.
Of the 72 c['.:::oo, 25
-~, 3% o~ t~c tot~1 Ro~~kon~ popalntio~;
only one cc:Jc
occur~cd
nuong
Llootly i:: -:-l:.o edul t populc.tion.
~ Sercwak Macao
Data of Firct Cace LEot
~,:::o
Cecoo
Doctuo
Popul~tiou
AttGck Rate Fer 1000 0.08 ·0.06
Jul. 1
Sept. 16
Lua. 10(1)
(1) Sept. 23
270 13 72
51 15 25
744, COO
EOI:.e:;kong
AUG. 15 Boc.t Dv/cl1oro 1.,..,,,<1 DvTcl1cro
3,OeO,Oeo 140,000 2,860,000
20°1°°0
0.02 0.18
47
0.02
4 These Paracholera El Tor outbreaks were not, with the possible exception of Communis.. China, extensive in scope; in both the Hongkong and SarawSk epidemics, adults predominantly were affected; the epidemic course where known, was relatively brief; mortality rates were not Significantly different from classical cholera. 2. Precaution~
Heasures Instituted -
On the basis of
these occurrences in the neighboring countries of Eastern Asia /
and the possible threat of spread to the Philippines, the uepartment of Health was alerted as early as July 1961. The Secretary
of Health immediately created the Anti-Cholera Committee that planned and coordinated all health activities geared toward the prevention of the entry of the infection into the country. All
quarantine measures "Which were allowable under the International Sanitary Regulation were strictly enforced. Closer surveillance
on the occurrence of cases of gastro-intestinal diseases was instituted. Immunization against cholera was intensified especial"
ly in areas that were believed more susceptible to infection. Improvements on environmental initiated. Sanit~tion
were prograLmed and
-
Campaigns for hee.lth education of the public on sani-
tary ways of living were vigorously waged. Through the vigil~ce
instituted, the first phses that
occurred on Septei;lber 22, 1961, were thus :LmnedLltely detected, die~osed
and hospitalized, and from then on, epidemioloeic dnd
control measures were started.
PREVIOUS EXPE:llENCES WITH CEOI&.A IN THE "PHI.Lll'?INES
Cholera uoed to be n ocriouoly tho Philippinoo. of occ~'renco
~ovoatcting
diooooe
in
While there io much controveroy on the dato fi~ot
of tho
cholera cpidcnic in tho Phi1ippinoo.
hiotoricc,l Z'ocor::lo 01.0";'[ tuo.t thore wno ::mepi<'iooic in 1628 llhicb.; while J.:ot hewing been Ciofinito1y eotcbliohcc no c:i8.gno~lio
".0
cllolern,
vmo be.ae':;'
~oit::'ar
on pntholOGic •.>! nor 1:;nctorio10;:;i-
eel cvilienceo, c.uthozoitieo, aO"IOVer, believe it nco c2010rc.
,
tarouch doduotion
c~u
oliwinntion.
Tho weicht of hiotcricc.1 introu~cod
proof £nvoro the opinion that tho infection weo tho coeot of ~io
from
to the Iolando by oerchnnt marineo. t~e Y08.1:'O
Suboequcnt1y, c?ideLdco occurrod durinG
1812,
1317, 1820, 1354, 1850, 13G2, 1888 to 1889 end 1902. Qunntitc.ti vo '::atc. io not, l::o~levor,
nV.:lilab10 cue o;:;.ly Ii ttlo
id~ornc·tio::::.
ctt:~ioo
of cc.rly '1?10rkcro.
T~orc
arc indi ccti oW.o J
hO"~/ovor,
thnt
-to bo
<'. pr.rt.~
the i::'ro-{, p:\nQcl::lic
Oil
recor(;. whic!:.l otcrtecl
in
oici.:.:r::. 'uno -::ritnccGocl the Q.piC:cz:ic i:;:l lIc:.r:il£l. , rcao~u:.tc0. t~C'.t all w:,y r...uC: c.ll night tohc ~t~ccto I.'lorc iillcC. 11i t:::. !.'1i th
puol.1 cc.rto loccloa
Qe2.G. bodieo.
Benoit eve;:;. ob::lcrved t:::.cc.t
t:l000
"co
.rere \Jell
6 the epidemic.:-of 1882, Father Cheuz reported that during the peak mor-e than 1,300 persons died in one day in the City of ¥lB.nila alone. h.oeniger, a German Consul in }lanila, reported that this
1882 epideLlic from August to October clairaed about 20,000 vict:iHS in Manila whose population then was around 400 ,000. lity was reported to be more than 755;;. The disease was reintroduced in the Isla.nds in 1902 from Canton, China, supposedly through a shipment of fresh vegetables, particularly cabbages which, upon being refused landing in Hanila, were thrown overboard in the harbor. Almost :iIrunedis.tely, the Within 48 hours, Norta-
people recovered the cabbages and consumed them.
cases of cholera ocfirred in the Farola District which was situated at the junction of the Fasig River and Hanila Bay. the same t:irae, an army transport left ~!ani1a
At about
and proceeded direct-
ly to Nueva Caceres and'the disease was discovered among passengers of the ship after trey landed, so that cholera appeared simultaneously in two widely separate places of the Islands. Some
epidemiological observations made were on the relation of the density of flies, roaches and vermins and the high humidity with small awount of rain to the increase of cases and that, the outbreak of the disease in Hanila always commenced among the poer seg;;lent of the;lpopumtion, frequently among beggars. Localized il rxi w i&,ispread epidemics occurred in an irregular but reasonably contiRuous fashion from the reintroduction of the disease in 1902 tbrough 1922 during which period the disease was Blt t.o have assumed an indigeous character, E,.,ide-
•
II " ~II ,
,
II
, I
7 mics of 3,000 to more than 18,(J()() reported cases with at least an 80;'; case fatality rate were reported each year from 1914 to 1919. During these epidemics, the role of the bacilli carrier in the transmission was pointed out. It was observed, for ex-
ample in the City of Hanila, th:lt o.t one time, over 7';(, of apparently healthy individuals in the i'ieisic and 'lando Districts
\
were found to be b~cilli carriers.
Due to this and other rela-
ted observations, it was believed thL-lt an epidemic got stD.rted by cholera. carriers and kept going on because of the continued existence of these c'lrriers. As a matter of filct, as a precau-
tlonary me,-:.sure, cholera c.lrriers registries were started to follow up the movements of the carriers. Scheoble, et. al., of the
Bureau of Science even elenonstrated that when a choleril. carrier was given a severe purge or when he ingested fooel or oi,her subst=ces which have the effect of producing a severe purge, the cholera carrier frequently wasconverlled to an actudl case. The followinr is '" vivid account on the usua.l start of the disease in a COJ[lj'lunity. months in the connnunitJT, No cholera had been present for
Then, ,m individual, usually from the ~s
verJ poor class, goes to work or fishing,
exposed to rain and
has been thoroughly wet all day; when he returns home tired, ,soaked to the skin, imel verJ hungry, he partakes excessively of any food that is availdble, often rice and fish, which probably
was cooked in the morning and kept the whole day.
Sometime
during the saIJle night .. he gets "cholera morbus" with vomiting, purging and crLUnps, etc., ,me. probably dies. Hhi1e it w~s
ad-
mitted that not every person who had an experience similar to
y
8
tbe above, developed cholera, it was believed that the majority
or at least a large percentage of cholera carriers who bad a s~1lar experience were l1ke~ to develop the disease. This was p3.I'ticuls.rly
observed in the 1916 epidemic in the City of Manna, when shrimps and small fisb which were then avai1a.ble in unusual. quantities were
suspected as probable vehicles or transmission. In 1911, tbe finding of non-agglutimble vibrios in surveys
conducted, is a matter of record.
In 1919, more epidemiological
-
investigations were conducted on the unusual. epidemic that occurred during that year. It was believed, for exampJLe, that water, milk,
and food, fanites and flies, together with improper foecal or
sewage disposal, as well as filthy habits of cases a.nd carriers, were factors that were responsible for the propagation of the disease. It was also pointed out that individual. susceptib1lity
to infecticn was increased by errors in diet brougbt about by scarcity and high cost of foodstuffs, predisposing the population to gastro-intestiml disorders in general, as well as by the increase in the amount of travel and iDmigration between the iSlands, provinces and the City of Manila. In 1919, a total of
18,213 deaths were registered with a mortality rate of 114.2 per hundred tbousa.nd population.
This
inciden~
was the b.igbest II
number of deaths registered fran Cholera in any single year. In 1925-1926, limited localized outbreaks occurred, fol-
lowing Wich, the disease
lar~
disappeared.
A resurgence
9
,
occurred in 1930 "lith 5,09') reported cases.
During the years
1931-1934, between 600 and 2,500 cases
.~I'ij:~portBdai.i1xru.ally.
Only 11 case3 were recorded over the next three years and no known cases following this time until September 22, 1961. As maybe realized, there is very limited quantitative data on cholera in the Philippines, prior to 1906 and 1914, as regards total mortality and morbidity, respectively, when even then, there was obviously too much under-reporting, of cases ~
,
especi~lly.
Table I presents such available quantitative data
on reported morbidity and mortality in the Philippines. A review of the pattern of occurrence and spread of the disease yields little productive information on,fhich to base a prediction regarding the locale possible future occurrence and spread. During the first two decades, epidemics of cholera
moved about the Islands ,Qthout recognizable pattern or particular geographic predilection. In contrast to the present epi=
demic (Fig. I-C), the highest rates during the ma,jor 1919 outbreak were recorded for Luzon and the Visayas (Fig. I-A). Du-
ring the last sip,nificAnt resurgence of the disease, 1930-1934, principal epidemic activity ",as confined to th e Visayas and Surigao; few cases were recorde~ on Luzon or 1''indanao (Fig. I-B). The seasonal occurrence of major outbreaks since 1919 (epidemics beginning in 1919, 1930 ~d 1933) demonstrates nne of two patterns of occurrence. The 1919 and 1930 epidemics show
rising incidence of cholera in ?1ay and June ',lith a peak of cases occurring in July or August. Epidemics in 1925, 1933 and the
present year show rising case incidences in September or October wi th a peak in cases reached in December or January.
In each
of the
epidemi~~,reported
cases fall to a low level of sporadic
)"
occurrences, lilithin three to f our months
aft~
10 the peak vias reached. The
pattern this year .oes not anuear to deviate from that of l)revioulil years (Fig.2).
Notabl:,!' since 1919, in the iJl1mediat,e year succeeding a significant outbreak, no resurgence of cases has bFlen ohserved. HOlever, sporadic cases are comnonly recorded during the year and, as follod.nll: the 1930 outbreak, it is conceivable th2t a resurgence after t fO
or three yearn
If the present epider,ic follo.fS the ed cases should reach very 10 T
t;B
ttern of recent years, report-
levels by late riarch and, although seattered ma,~or
cases may1:e revorted through the end of the year, a the disease {ould not be antici~~ted thi8~ear.
resurg'nce of
11 ~
Table 1 PHILIPPINES
CHOLERA: MORBIDITY & MORTALITY No. and Rate (per 100,000 pop.) 1906-1960 Cases Years Number 4-
Deaths Rate Number 6061 118 11110 8566 1202 124 186 2341 398 8235 3123 %l24 18213 1194 41 12 11 26 588 233 3 8 3979 184 441 1801 636 3 1 1 Rate 13.8 8.6
.-.., :-
1906 1901 1908 190)
-'
". ~
1910 19l1 : 1912 1913 1914 1915 1916 1911 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 199;J 1930 1931 1932 1933 1934 1935 193 6 1931 1938 1939 1940 1941-45 1946 1941 1948 1949 1950-60
No data No data No data No data No data No data No data No data 3013 1488 11623 13082 6236 18213 1810 61 f3)
available available available available available available available available 32.0 16.0 116.0 101.0 %l.0 114.0 19.0
201·1
98.2 81.0 1.4
2.0 24.6 4.1 83.2 36.1 58.2 114.2 11.1 0.4 0.6 0.0)
19 38 619 334 10 13 1 50)6
1941 621 2542
925 9 1 1
1.0 2.1 0.05 0.14 0.01 31. 6 1·5 4.4 11. 6 6.3 0.06 0.01 0.01
0.2 4.8 1.8 0.02 0.06 22.1 5·1 3.2 12.5 4.3 0.02 0.01 0.01
No data available
No data available
No cases and deaths reported
"--~
I
I
FIGURE
I-A
12 PHILIP PINES CHOLERA: GEOGRAPHICAL DISTRIBUTION RATES PER 1000 POPULATION 1919 EPIDEMIC IEGEND : \1 J
0- 0 /~
C'i -
0.01 - 0.49
~} - 0.50 I:::\\J - 1.00
+
- 0.99
.-..., .' \. v. . ;~
.' J ,\ Vi
J) C: ( . .
. /1' \ - - ---' ,) /
1 :'1.:_', ; : ; t ~"""')
Ci:::...--:-\ I/\'.\J · ..... )
v,.,
:.<:;(; . . :5~<~i
tJtp~;J(~,·Y) AfY} ,>(~> '. ) 1 ",~ 'j....
\.\\).r:-:::; <1'c'"
. (~)
)\._~
\..)
. ::; >' "~~i\.
! I
.:\,.(f(v ,j~ \~'. ~;; ..:-.:::-
Vi \, { - -..
'/ ~\
:")
j\
Ii' ~
'-
>~f)~~.~;.r--I
-:'
\l) }~~'l "
~
/ C~:-,
./
~ill
r/
\
/ /\. )~ J
,:.) 0
--
FIGURE 1-B
13
CHQ~!...GEOmt'.PBTCAi.'DISTlRIBmION T£8 PER 1000 POPULATION 1930 EPIDEMIC
PhLLIPPINES
LEGEND :
ffij]
~
- 0 - 0.01 - 0.49 - 0.50 - 0.99 - 1.00
f2.tt1
+
-.'"
~;::J
V -,
"( (,'. {
r\
D \
~...J
)
\
}O
/
(;
FIGURE
l-C
14 PARACHOLERA EL PHILIPPINES RA TOR: GEOGRAP TES PER 1000 PO~~L DISTRIBUTION 1961 _ 1962 TION . .
.~
I)
LEGEND :
r-"·· _J 'iT,:;c ......\ ~..
0
ulilWO - 0.01 . Bi. c-:fZ·
:---,.1
-
o. 49 0 .50 - 0 99
- 1.00
+•
~ . ... ~
1
j ~
.>.J
~ ~
.t,
7000 6000 C
FIGURE
2
T
I
\\ \ \ ! \ \
PHILIPPINES MAJOR CHOLERA EPIDEMICS SINCE 1919 CASES BY 1-10HTH
5000 A I
S 4000 . E
Ii
/1961-62
3000 S
Ii ../
l \\ "
\,
\ 't:,
~t/ o~ ~
t/ \<
I /\
1930-3 \ .
...____ ______
~~
______________
/1919-20 ~~
____
~~
_________
1-1 500
A 1-1 J
J A SON D J
F 1-1 A M J
J
A S 0
./ i
/\ \
c A
300
/ ,,/ .I !
/
S E
100 S
,/
. . . V\/193 ......1925-26 O·
2
~
-33
500 C A
400 300
S E
200 100 ,/1933-34 0
S
16 THE PRESENT EPIDEMIC
1, riz~d
Thq Probleo - Extant ond Mggnitudo -
Caeeo charac$o-
by oudden oneet of acute and profuse, colo~lcoc diarrhea, in
vooitina, oevere dchydration, ouccular craops. cyonoois und -'-
severe caocD. collapse, firot occurred on Septeober 22, 1961. The first cases trere adult reoidents of Paudacan, a district in City of i4Elnill.'li and Were aoon~
the
those associated with ship docks Following this iniin
by reoidence, occupation or facily contact.
tial occurrence, caseB shortly thereafter appeared elsewhere Manila nnd in noighborinG citico and provinces.
Spread oontinued
to involve successively areas in Luzon, the Visoyae and Mindanao and Sulu, firot appearing alone the coastal arcas. So that, since
the occurrence of the first cases on the 38th week of last year (ended September 23). until the 11th week of the current (ended March 17), or a total of 26 weeks of continuous occurrence, a total of 14,675 cases and 2,064 deaths have so for been reported from 45 of the al provinces and from 33 of the 39 cities of the country. In 'L nl~ost
all cities and provinces affected, bncteriologiond~
cal coufiroctiell of one or nere early cases has bGcn Bureau of F.esearch and Laboratories. In about 50~
by the
of cases in Ma-
nila and suburbs and 20% of- all cases, the vibrio El Tor has been identified. 1.1~
Epidemic Curve - Table 2 presents the reported week-
ly incidonco of cnses and deaths throughout the country.
>
17
PJ..tlJ,.CHOLERA EL TOR; REPORTED CASES & DEATHS BY WEEK EPIDEI,!IC PERIOD, 1961-1962
Table 2 PHILIPPINES
38th 39th 40th 41st 42nd 43rd 44th 45th 46th 47th 48th 49th 50th 51st 52nd 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 16th 11th
-
Week
Ended Geptccber 23, 1961 Scpteober30, 1961 October 7, 1961 October 14, 1961 October 21, 1961 October 29, 1961 November 4, 1961 N6vccber 11, 1961 Novecber 19, 1961 Novocber 25, 1961 Dececber 2, 1961 Dccecber 9, 1961 Decocber 16, 1961 Dccecber 23, 1961 Deceriber 31, 1961 January 6, 1962 January 13, 1962 January 20, 1962 January 27, 1962 February 3, 1962 February 10, 1962 February 17, 1962 February 24, 1962 March 3, Hl62 March 10, 1962 March 17, 1962
No. of Cases 3
No. of Deaths 2 17
61 58 123 125 510 747 1094 911 874 823 1302 1452 1110 726 701 942 989 725 302 218 295 197 125 151
7 14 __ 21 17
79 86 93 126 95 233 280 164 126 132 114 154 90 41 39 31 2T 12 14 6
t.11: 14675
2064 It
Three peaks of incidence are apparent in Fie. 3. will be noted that the first of these penks occurred
~uring
the 45th week ended Novecber 11 and reflects principally
the
epidemics in Cnpiz nnd Bacolod City in the Western Visayas; the second, occurred on the 50th week ended Dececber 16, and reflects priocipal1y the epideeics in Boho1 nnd Snenr in Eastern Visayas and in Lanoo del Sur in Western Mindanao; ~hile
the third peak occurred during the 3rd week of the current
FIGURE 3 PHILIPPINES PARACHOLERA EL TOR: REPORTED CASF..8 BY WEEKS EPIDEMIC PERIOD, 1961-1962
....... '\
N
u H B E R
1600 1400 1200 1000
."
0
F C A
800 600 400 200 0
....
S E S
"'"" f L
38
40
42
44
46
48
50
52
2
4
6 1962
8
10
1961
W
E
E
"
"
S
lj' year (ended January 20), reflecting principally the epidemics in Cotabato in Western Mindanao and in Sulu. It will further be noted that as of the end of the 11th week of this year ended March 17, nfter a period of about six conths of continuous occurrence in the country, the is definitely on its tail end. Only in certain ar~as
epidecic in Eas-
tern Mindcnao and Sulu are scalI foci of infection. 1.2. Pattern of Spread - That the pricary focus of the current paracholera EI Tor epidecic was Manila, has been Dore .>
or less definitely established thru detailed investigations cnde by field health workers and the Disease Intelligence Center on the first cases reported on the 38th week ending Septecber 23~
1961.
Although subsequent reports froc the field showed that there were clinically diognosed cases of paracholera in several other areas, as early as, or even earlier than the first cases noted in Manila, further investigation revealed that those casco had their very recent sojourn in Manila. The first
case in Placer, Masbate ccce froc Manila on Septecber 20, had symptoms of severe diarrhea and vomiting upon arrival and died on Septecber 22nd. The case on Septeeber 21, 1961, froc
Tacpogo, Tagudin, Ilocos Sur arrived froc Manila daysoo'Ybre'.'the clinical symptocs set in. «uezon City VIllS
ab~t two ./
a rattan worker socewhere
r
And another· froe
Manila; had It can
symptocs on Septecber 23rd and died the sdne day..
be stated with reason, theref.ro ... that the primary focus of the infection was lfanila. From then on almost simultaneously, other cases occurred in and around Hanila and suddenly sprouting in the fishing viLiages and coastal toms of Rizal, Bv.lacan, Cavite, as far North as Z~
bales and Bataan in ReF,i on I and later to the sov.th in Lapuna, Batangas, and Quezon provinces, all along the China Sea coast (fie:ure 4) Ca('!ee oc.urrec., apparently ,Tithnut rhyme or reason in remote barrios of these provinces, most often sin?ly in f&lilie5 and unrel.ated to one R.n~)ther.
The incidence in Hanila and Central
Luzon rose to a peak on the 43rd week and then went throuI"h a long period of decline to a seemin~ly
endenic level on the 50th
week, interrupted only on th~ 46th week by an institutional outbreak at the National l'lental Hospital. I t may be "lOrthwhile menfte~ions
tioning that the in-land and eastern provinces of II (Northern LUllon) esc"pe infection
I and
until much later; Tarlac
and Cagayan on the 49th w~ek, Is~bela on the 3rd week, 1962. II-)COi!) Norte, l-1t. Province, Abra, and ported any case to date. l!Jhile Central Luzon .fas reachiD,l: its p&"\k inciclence, cases started to appear in Regions V and VI; in Capiz, Aklan, Roxas City, Bohol and Samar on the 41st and 42nd weeks. In Region V, the first cases were r e=rtli. on 1 he 42nd week for Ca piz and Roxas City. 4 week aftermrds (43rd week) the total cases reported for the region sweller\. up to 317, ~ \ I
Nu~va
Vizcaya have not
r~
•
'f- ~.
"1
<:t '" ::.
I t,1
t.
"I
.~
~ !
FIGlIlE 4
"
'-
- - .....··/PARAClI)D!'.RA EL TOR: GEOGRAPHlr1>ISmIBlJV:OH ' OF C1.SIS, 'l~ITU ~
Y--..
~-~ J \
\ ~
.....
) "
N .l> ~ > ,
\ \.,1 /' l
(
_...,r---....../ '\' \ T ..........
A-~ ~.
~
/
,I J>
,r
A c;. ,_
*'
.\
t·~i..}"-:VA
I \~
r
\
J.~
\ ( I
~"""""'---.J ~ ., ~," ~ !~ I
\f
y f'...
\, ':.
,.
f>.
".
( I
• "
•
•. .. # - ••
~
..
.~
.
",._
.....
. ,
,
-, I\' E •
L A 1".'" U
t..:
A
;'lith 54 deathst the infection then had soread to Aklan and Iloilo City and continued on to l'~egros Bccidental, I3p-colod City, 0il<.'.y City, 0an Carlos City and much lCl.ter to Antique, reaching a peak total incidp..rlce of 581 cases on t.he 45th reek. Althoup,h the epi~enic curve presented forthis region, lOoks like 11
common vehicle curve, blo
111
up h~r the hip,h attack
raises in Pcmay Islancl.and Negros Vccidenlf,J. cursory epidemiclogical investip:1\tions r.lc-;.de, revealed that the cases were motsly from cOl1stal to'l1S; rere unrelated, anrl as in the F.anila
area, also appeared sinply in families.
In Region
VI,
suspicious cases were reported in Bohol
on the 41st ,-leek but las not follo'N'ed by other C1\ses until tw-o weeks after. In SaMar, the hardest hit province in this Region, there ~as
noted a slight rise in incidence of gastro-enteritis onl~r
in Catbalo<'an on the 42nd.reek, but itras week,
on the 44th
men l'L0re than a hundred cases '"ere record"-.,in Laoang,
that bacteriolor,ical confirrl):,tion for - Paracholera El Tor ·ras ohtained. Un the 44th reek cases and deaths were also reported in Calbayog city, then followed Cebu province and city, Durnaguete City, l,egros Uriental, Leyte ~ur and Norte, vrrnoc City, Tacloban City, Toledo Cit~r
and Lap Lapu Cit:T in ranked leel~
orner reachinp. a peak on th,' 49th deaths. In "ePion VIII,
of 595 Cl'l,Ses and 101
1.'
cases and 4 deaths were first re-
corded on the 45th reek, most of ·lhich rere from Davao City, then the dis ease s poradicall~r spread to Butuan City,
23 Snrigao del Sur, Cae-ayan de Oro Cit~r,
r.ingoog Ci t::r, ;iisamis
gulc.r downward fluct''>."'.t:i.ons
PT8.d1'2.J.l~·
rose to its
m~,xh\UlIl
dence rOGe to its neak. ''''.on tre CH:-ve had the 5th and 6tl1 weeks.
i'.
steery f8.1l on
In Region VII, t11.e first six 28.1'ac 1.>.01ero. ]';1 Tor cases wi th 3 deaths were recorded in To.nao Sur on t>e 4flt~;
week 2.f/
tel' a m:lsli:n c· ief w"o died of the dise8.se in Davl'.o W'.S broo.ght back to Ii:mao Sur for the burial rites. An exnlasive o1.~t'-eak occ'.~red
2.fterwarc.s cans:i.IF t"e e"irIe'ic Cl'IVe for sl~den
••
t>e rer:ion to rise to a
stee:.· 11ei'ht of 372
cases and
134 deat',s two weeks later, th", disease ra',)idelv s')r8:ld to ot~1er
pro·d.nces 8.nG ci.ties in the rerion; to rfarawi Cit-"
Suln,
:tlie'an City,
ranao
del IJorte, Zamhoow,a del SPI, Ozam.iz City, City f.nd Zamboanga
;:,C.r,1~'0,·.nf'a C· t:.', ·'is2.,111s 0cciden'al, "'··'.sil}.n
del Norte •.\nother peak
Wl.S
eX'Jerienced in t"e reptonal e,i--
tensity wit'in t 1'e 1st to t',e 3rd weeks of 1962.
Then the
inc:i.o.ence rradnaJJ;T declo.ned on t'18 s\,.cceed.inr weeks inter-
, die occ ' )rrence of cnSeS in Za'.J1)02.nra del ;"orte. II
,
(t.ra:1sj.ent) occllrred in ;:as':>e, ';,e on tl'e 32th week, t)'at other cuses \-lere re;)Qrted. A :,ev in "ar'.oEB towns lmtil a
II I ,
sporadic cases continued to oeCl'I m':Ifl':ler 0:;," 40 caees was . t
II
i12.X~i.:'1"J".
.~
24 '-
reached on t,',::! 50th week. ceecinE; weeks.
Then it slowly subsided on the sucViaS
One transient case cooing froD Manila t~le
re~
ported in SOrSOI:;On on
5th week.
Six weeks later, on the
11th week, three other cases occurred in one district (Sanpaloc) in the province verified by laboratory exanination. About tbe same time these cases were occurring, suspicious cases were observed in the municipality of Caaagong, Caoarines Sur. Rectal swabs taken froo 11 cases with diarrhea yielded
three positives for paracholera El Tor. Figure 5 presents the epidenic curves in the respective
-
.
regional areas.
The sequential spread of cases froD the ini-
tial focus in Manila naybe clearly noted • . 1~3~Morbidity
and Mortality Trends - As stated earlier,
since the oceurrence of the first cases on Septeober 22 of last year and up to the 11th week of the current year, or a period of 26 weeks of continuous occurrence of cases in the country, • II
II
a total of 14,675 cases and 2,064 deaths froD 45 of the '~provinces and 33 of the 39 citie-s, have- thus far been reported. Attack rates by reporting- area are included in Table 3.
•
, I
Figure 1-c tack in the
~ves
a comparative idea as to the intensity of atareas affected. th~t
~arious
It will he noted
in Northern Luzon, cooprised by Re-
gions I ansl II, end in Central Luzon (Region III) I as well as in the Bicol area (Region IV), the average attack rate has not exceeded 0.5 per thousand, with the exception of the Lucenn City and the province of Masbate, where the. respective attack I
'""
FIGURE
5
200 100
PHILIPPINES PARACHOLERA EL TOR: CASF,s BY HEEKS AND REGION NORTHERN LUZON
Region I Region II
1961 - 1962
Region III Mental Hosp.
I .. .i
l ! !
/\ ~'"
,
\
Region IV Region VI Region V
\
\ \. 100 .,~
\. ...' ......
-.,.-
O~~----~~~~~~~~-~---~~~--'--------~~-~-~-~-~-~~~--~-
500 400 300 200 .•••...... ...•.. /
MINDANAO - S ULU ,
Region VII Region VIII
\,
...
100 0~3-8----40----4-2----44----4~6--~~~5~0---5~2~~2~--4~--~6~---
1961 H E E K S
1962
26
rates have been slightly nore.
In Northern Luzon, the provin-
ces of Abrn, Iloc08 Norte, Mt. Province, La Union, Batanes and Nueva Vizcayn, and the city of Baguio have not reported any case. All the areE';S in Central and Southern Luzon have been infected. However, Pulawan and Mindoro Oriental have not also reported any case. Particularly notable is the absence of cases in three pro-
vinces in the Bicol region - Canarines Norte, Catanduanes and AIbay - and in the two cities therein, Naga and Legaspi, through which pass considerable traffic to and fron Manila vily infected adjacent islands. v~d
the hea-
It is only within the last two
weeks that a few cases started to appear in the provinces of Sorsogon and C~arines
Sur.
L1 the Visayan Islands, conprised by Region V - Western Visayas and by Region VI - Eastern Visayas, the infection was allover although in varying intensity, as all provinces and cities reported cases.. In both regions, the attack rate average
slightly less than 1.00 per thousand, with the western having slightly nore than the .astern areas. E';nd Al(lan ~illd
The provinces of Capiz
the cities of Roxas, Bacolod And Silay in Region
V, as well as the province!! of Sru:wr and the City of Calbayog in Region VI, notably had significantly higher attack rates, well over 1.00 per thouscnd, with the cities having relatively higher rates than the provinces oentioned~
Western Mindanao ana Sulu, Region VII, apparent1: average the highest att2ck rate for the regions, more than 1.00 per thousand, wi tb the provinces of Suiu and L::mao del Norte and the ci-
27
ties of Marawi and Basilan, having attacll rates ouch higher than the other areas in the region. In Eastern Mindnnco - Region
VIII, the average attack rate was less than 1.00 per thousllnd with the provinces of Surigno del Sur, Surigao del Norte and Cotabato, as well as the cities of Daveo, Cotabato and Butuan having slightly higher rates than the regional average. Sioilarly, it will be noted that all provinces and cities in Mindanao were with cases. All of these dntn on the oorbidity [Iud oortality were based on reports subnittec1 by the field health officers. recognition nnd possible. under-r~portin8 ..
Non-
-
eo!:ccially of oilcl cases was de~~nition
For nn insisht on a nore accurate
of the
extent and oagnitude of the probleo as it occurred in a 1ioited selected area, reference is nade to a snaIl epiQ8oiological study, conducted jointly by the Disease Intelligence Center and the l'lnl ter Reed Arny Institute of Research in the o'.micipality of Duoangas in Iloilo. Vlhile this study was specifically designed to deteroine the oode of trancoission of the vibrio in the given population, through the closer surveillance instituted, Dore cases were recognized and hence, a oore accurate deteroination of the possible cttack rate was available 30,000 ha~ 0
) ../.
Dunangas, wi t!l a population of
e
a total of 71 cases during the period Noveober 12 to
II I 'I
Deceober 15, 1961, or an attack rate of 2.4 per thousand popu·· lotiol.. The cases were distributed throughout tIle locality: and
the highost attacll rate for one barrio was 13 per thousc.nd popu-
28
.
"
lotion • 1.4. Qaae-Fctalitv Ratios -
Aa oaybe noted for the over-
all reported cases and deaths for the whole country during the duration of the epidocic period, the case-fatality ratio averages 14 per cent. This ratio, of course, exhibited weekly varia-
tions, with the highest recorded during the start of the epidenic. Most s:Lllnificantfaotors in the cause of death, have been ~isense
failuro to seek or obtain treatoent early in the
course,
,
inadequate fluid therapy nnd the presence of significant disease pathology, prionrily chronic in nnture. Deaths have generally
been proportional to the nunbar of cases reported by age group, with tho exception of the extrenes of age, where case fatolities have been observed to be significantly higher •
. '
Republic of the Pnilippines Dernrt!<'.ent of Health DIS:S.ASI~ INTELLIGENCE mNTER ?-anila PIIILIPPUSS R1!:P('lflT~;rFpAl.A:~R.lI~~d,A ~1 PROVINC!~ &
29
T\ll.
CITIFS BY 1-lB7KS
1961 - 1962
------------------------------------------------------------AREA REGION NO.3
-------------------------------------------------------'~~~ Total
:38 :39 : 40: 41: 42:43 :44 : 45 : 46 : 47 : 48 : 49
50
51
52: 1
2: 3
4
5
6
7
B: 9 :10
11
No: Rate
Hanila Rizal Quezon City Pasay City
C D
C D
C D
C D D
3: 28: 16: 36: 3:21:,9: 12: 2: 5: 2: 2: 1: 2: 1: -: 22: 11: 15: 20: 21: 29: 4: 4: 2: 3: 3: 2: 2: 1: 8: 8: 20: 15: 4: 1.: 1: 4: 2: 2~ 2: 2: 2: 4: 2: 4: 8: 2: 1: -: -:
1:
Nat. Hental Hosp. C Bulacan Ca vite Prov. Cavite City Trece Nartires Tagaytay Bataan laguna San Pablo C D
-.. -.. -:
-. 2: 10: 3: 1: -: -: -. -: -: -: 3: . . -. -.· -. 1: -. -.· -. .: -: -. .. . .. . 1: -. -. -. -. -. 6: 126: 43: 36: 1: ¥" •
9: 6:
7: 10: 12: -: -:
'-:
.
7: 12:
3: -:
-.. -:
2: _:
-:
3: 1:
2:
--. _.. _.. 0_:
2:
2:
1: -:
5: .;..: -:
4: 4: _: -: -:
2: -: -:
_. _.· · 3: -: -:
3: -:
_.. _.. 1· . :
2: -:
1: -:
3: -:
1: -: -: -:
,
.
5: 2:
5: 11: 22: 14: -~
1:
-:
C D
1: 1:
C D
1: 1: 1: -:
6: 12: 12: 2: 1: -: 6: 2: 3: 1: 1: 1:
-.· 4: -. · 5: 1:
6:
-: -: 1:
1: ,
3:
-;
-:
8: 12: -: 2:
-.. 3: 2:
7: -:
11: -:
C D
1: -: 5: 1: 3: 22: 1: 7: 1: 4: -:
-. .... 2: .
-.·
.
... : -: -:
5:
-. 19: . 8: -.. -: ,
-: 1:
1:
-: -:
-: 1:
-.
-: -: -: -: -: 1: -:
·
1: -:
201 15 164 19 68 10 2f3
: : : : : :
-: -: -: -:
-: -:
1: -:
3 239
4
4:
-:
2: -:
-:
. -. -. -. -. . -. -. -. -. -: . -: -:
3:
3: 4: -: -: -:
2: -:
1: -:
1: -:
1: -:
-:
-:
-: -:
-: -:
-.. 2: ,
.
126 3 44 5 21 1
4
0.16 0.01 0.19 0.02 0.16 0.03 : 0.20 : 0.02 :39.83 : 0.67 : 0.21 : 0.004 : 0.14 : 0.01 0.36 0.07 : 0.21
C D
1:
C D C D
.3: -:
. -. -. · 1: -: -: -:
-. -: -:
:
·
:
1 : 0.13
-:
-:
C D
1: -.. -.· -..
-: -:
-:
-: -:
1: 1:
-: ,
1: 1:
. -. -: -:
-: -:
-: -:
1: -: "
,
.
-.
32 : 0.20 9 : 0.06 11 : 0.03 1 :0.002 2 : 0.03 1 : 0.003
<"-
I
"
.,'
",
(
/' .'!
*, ~-.
(
J
",
-)
'. ., '
~1 '
~--------------------------------------.
'
..
-----------------------_.6: 1: 6: 2: .3 : .3: 6: C Pamps.nga . . 1: 1: D 1: 1: 1= -. 8: 11: 4: -. 1: 1: 15: 8: C Bo.tangas .. 2: D -.. -.. 4'. 2: 5: _. 1: 2: C Lips. City .-. . 1: D 1: C Nueva Eeija _.. 3 : D -!
AREA
:38 :39 :40 :41 :42 :43 : 44: 45 : 46 : 47 : 48 : 49
50
51
52
1
2:.3
8:
4: .3 : 2: 1: 2:
4:
4:
·
7: 8: _. · -'. -. _.· -.· ·
..,.-1: -: 1:
4
5 1: II
6
7
g
9
-----_._-Total No : Rate 10: 11 ----- ..61 6
.30
1: 1:
·
60 14 .3 1
0.09 0.009 0.09
0.02 0.04
1:
0.01 0.009
Cabanatuan City Quezon !'rov.
Lueena City Romblon l.findoro Oriental !vhrinduque TOTAL FOR .
C D C D D D C D
· 10:
5 1: 1: 21 : -: -:
-: -:
-: -:
-: -:
-. 2: -:
2:
1:
11:
11: 1:
5: 1:
3: 6: -:
4: 10: 1:
-.
1.3 : 2: 7: .... : 2'6: .3:
7: .3:
22:
-.
2:
5:
C D
-. · 2:
-. -. 15: 1:
.3:
5: 1: -:
6: 1: -. -.. -.. -.: -: -: -:
. :
1 1
4:
C D
·
2: -:
20 : 10:
-.· -: -.
1:
. -. -: -:
2:
105 17 29 1
-. -. . -.
-:
3: 17: 31:
1:
61 5
-:
.3: 1: -:
6:
-.
76 19 1
0.01 0.01 0.16 0.03 0.55 0.02 0.43 0.04 0.31 0.08 0.003
REGION NO • .3 REGION NO. 1 Zambales Iloeos Sur Pangasinan Dagupan City
C.3: 59: 55:112: 92:136: 49: D 2: 17: 7: 12: 11: J,.?.!-l.:
60: 7:
77: 177: 1.35: 5: 8: 7:
81: 4:
76: 66:
35: 27: 21: 27: .38:
" • 16 • _ _ l' .t..!-.-..!.. ~..
'.3 • 7 . . 1. • =..
4: 5: 4:
-.
-,~
__ ~_-:~ ...__:_. __.2..J..2JL..:_'?.!.92
1:
1:
-;- 1341:- 1.76-
C D C D C D
2: -:
.3 :
-.
4: .3 : I ' 1: 1: <
'. .3: 18: 17: 2: 1: -: -.
7: -:
-. -: 20:
.:
7: 16: 21: .35: 2: 1: .3: 1: 2: 1:
C D C D
8: -:
9: 1:
4: -:
8: 1:
". -'
Tarlae
'-WTALFOR ;reGION NO.1
-c: : 2: 3: 5: 15 ;-Z-2';-47:46: 28: 25: --17:--17: 14: /1: 1:217' 1: - I - : - : 1: 3: -: ...: 1: -: -: 1: -: 1: -: -: -: -: : : : : : 20: 0.009 / _ _p_~_:_=-=--=-:_2..!.....2..:--.1:_ . .4.:.----1.! - - - - - - -..'_._- - - - - - - - - - - - - - - - - ---.-----------... -~
. -: 1: · .... : 15: 17: 17: 14: 1.3 : 6: . -.· -.· -. -. -: -. -. .. 1: -: -. -: -.· -. . '-: · . -. -. -. -. -. -.· 1: -: .3: 1: -. 1: -..· -. 1: -: 7: 1: -: ,
2: -. · ... -.· -.· 4: -. 2:
.
16 1
0.07 0.004 0.16
~:
-: -:
-!
-: -: :
-: -:
1: -:
181 9
58 5
0.01
0.16 0.003
. ~
0.004 293 : 0.1.3 ;2
33 3 5
0.49 0.04 0.01
I ,. -
.-.
(,
,
'",
('
J
1
31 AREA :38 : 39: 40: 41: 42: 43: 44: 45 : 46 : 47 : 48 : 49 50 51 52 : 1 2 -----.-3: 4 : I : ~": ~ "
,------------_.._--------_. C D
8
9
10: 11
Tot aT 'No : R6.te
REGION NO. 6 Bohol Sawar Oalbayog
6: -:
-: -:
;..: 1: -: 1:
8: 2:
C D
C D CD
Oebu. Provo Oebu Oity Iapu-le.pu
11: 12:195: 267: 4: -: 13: 27: 71: 29: 14 . 12 . :' D ..
2: 22: 38: 64: -: 2: 6: 277: 311: 273: 479: 37: 95: 41: 84: 12: 10: 19: 30: '5 . 3 . 6 ' 4' 37: ')': ~ 1: .. .. .. •
f)
5:
.:
7: 1: 3: 1: 1: -: 2: 317 : 24: 2: -: -: 315 : 151: 159: 37: 22: 70: 5'8: 15: 14: 7: 5: 8: 9: 1: 21: 2402 : 22: 6; 2.1 : 2: 12: 13: 5 : 4 : 2 : 1= 2 : '2 : - : -: .393 : 13: 8: 11: 10: 7: 8: 7: 4: 1: 10: 6: 1: 1: 1: 259: . -' '5 . . 2: 5: 3: 5: .;;.: .;;.: -: 64: 3: .'~1J: 27: 15: -: 4: 4: ~: 95 :
166:
-.. _..
-.. -..
0
__
_.· _. . _.. _.. 2: 2: 1:
0.49 0.06 2.31 0.46 3.09
2:
1:
0.76 0.09
C D C D
3: -:
3: -:
7: 1:
3: -:
:iegros Oriental
DUInaguete
C D C D
6: . _.
-: 39: '14' -. _
1:
Le,.e Ormoo Taolol:la.n City TOTAL FOR . ,
C D D
o C
?: 6: 20:
2: 2: 11:
38: 19: .... :
-. -: -.. -.. -.· -.. -. · -. · 12: 3: 3: -: -: -: 3' 1: -: -: -: -.· -: 1: 4: 5: 1.3: 1: 1: . -.· -.. -. -. -. -. 7: 3: 12: 3: 10: -: -: 3 : 1: -: 0
4:
9: 1: -:
6:
-: 1: 1: 1: -:
3: 2: -:
-: 2: 2:
1: 3:
1:
4:
6:
1:
1:
-:
_.. 2: -:
22 : 0.02 0.17 4 : 0.01 1 : 0.02 1 :0.02 64 : 0.11 i8 0.03 28 : 0.74
48
J.: ~:
3: -:
82 41 33 10 82 18
3: .;....:
2: -:
6: -:
1: 1:
5: 1:
-: -:
-: -:
2: -:
-:
0.07 0.04 0.49
D
_REGION
NO~
C D
-: -: "-: -: -: -: 0.15 8: 15: 19: 11: 4: ;..:. -: jI,: 1: 1.42 ~.: .: 2: 4: ,7: -: -: -: -: -: 1: .: 0.31 --6':'":-11: 12:267: 299: 329: 346: 367: m:419?2i2:-66=--96':129: 89: 41: 30: 17: 19: 19: 13: 7:24: 3li'j--:-----: 4: -: 28: 41.: Mi: 98: 6l.!-101: 87: 17: 2.7: 25.: 23: 27: 6: 5: 4: 1: ..:i!_J.L._-...L,__~_L..6m..: 1: -: 2: -: 6: 1: 8: 2: 6: 1:
6:
4:
-:
-:
".:
R'EGI0N NO. 5 Capiz RoXE'.s City Aldan
o D C D 'J
1: 36: 20: :111: 43: 7: 9~
7:19J:240: 171: 76: 76: 31: 10: 18: 10: 10: 12: 14: 14: 9: -: ·4: 33: 10: -: 11; 69; 1:
2: 20: -:
1: 18: 1: 23:
1: 13 : 1:
2: -:
1: 1: 23 : -:
25 : 13 : 15: 1;
-. 8:
5:
1:
5: 1:
-: 5: 14: 11: -!
1:
-: -: -:
'-:
3: -:
-.· 2: -:
89E
70
3.13 0.211-
322
6,06 L). J:::
r:
"
4.3:
64: 7:
46; 5:
J.: 23 :
-:
1: -!
-: -:
17 -: -:
-: -~
6: -:
-: 16:
-: -:
-: -~
4:
-:
2:
341 35
1.40 0.14
1 ,
~,
(,
( ~,
;
J
.' \
..
-- - ----.-----.--- .--- -_.- .--... .. _ _ _ ... ~
-------. -------..... - ......-.-. -- -- --I~: ....... _ _ ... v ........ _ _ ... _ .... _ .. _ _ _ _ _ • _ _ _ _ _ ~ _ _ _ . . . _ _ _ _ _ ....... _ _ _ •. _ . "
....
---_._- --- -.........--.---------....------ ......-.-_._----.....---... _-- ...-_..------- ---_._._-...t-.a --. l .
32
'.[' 0
: 33: 39: 40: 41: 42: 43: - _ _ _ ~ ... _ • • _ _ • _ _ _ _ • _ _ _ _ _ _ ... _ _ ,~ . _ _ . _ .... _ _ _ . . . . . . . _
45 : 46 : 47 : 48 : 49 : 50 : 51 : 52 : 1 : 2 : 3 : 4 : 5 : 6 : '1 . .., _ . _ _ _ ...._ _ ' _ . _ . _ _ ._:_~ _ _ _ . . . . _ _ - - -.... - . - - - -. . ' - - - ...... _ _ _ ...... . . - _ _ ,. _ _ _ _ ...
~
13 : 9 : 10: 11 :- Xo ~
: lhte
_ _ _ _ ......
_'-0_ .... __ .. '... _ . ._________ .. '................. ___ . .
501 : 0.57 22 : 0.03 C Iloilo CHy 82.: 0.50 3: 33 : I~ : ... ; D -; 1: -: : : 3.: 0.02 -; T8gros Occidental C 72: 22: 25 : 8: 7: 8: 19: 14: 5: 4: 2: -: 303 0,27 D 7: 3: 1: -: -: 1: 4: 1: 1: 1: -: -: 4: 25 0,02 42('; C Bilcolod 1: 1: -: 1: -: 1: 226: r/: 6: 7: 6: 19: 5 : 9: 3: 3.33 D -: -: -: -: -: -: -: -: -: -: -: 1: 19 : 24 0.19 2; SHay C 1.16 -: 2: -: -: -: 2: 23 : 75 .- , .... : " D -, I: I: -: -: 1 -; '-: -: 3 0.05 -' ~~an Carlos C 11: 14: 11: 6: -: 6: 3: 7: 58 0.43 1" 1: 2: 1: -: 1: 1: 1: ... : 7 0.05 C -; Antiqne 6: -: 12: -: 1: 163 0.63 7: i~ : 4: I: 32: 69 : 27: 0,02 -; -: n -: I 2: 1: 1: -: -: -: 1: -: -: 5 __ ....... __ _ _ .. ______ - - . . ___ .._ _ _.___ ._•. ___ ._ _ ... _ _ _ _ _ .. ___ ..... _. _ _ _._ ..........__ ..__ ,_. ,.._v_ .... ____ ._ ......... _ .. ,_ _ _.... _ ... __ . ____.___ .-_ _ .__ ._ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _.... _ _. _ ......__....... __ .__ .__.. __ .,. .... Iloilo
C
n
24: 6: 2: 1:
10:
1:
64: 77: 2; 1: 10 : 21: 1: -: 1: 61: 36: 20: ...;..: 2: -: 114: . 14: U: -: 3 ; 1: 10; 7: 29: 55: 4: 8:
. 2:
57:
58: 45: 1; 1:
32: 28: 20: 18: 1: 2; 1: -:
7:
1: 3: 1: 1: -: -;
-:. -:
-:
-.
-.
.
.J
~
_~
TOI.eAL JOH ')'DO"T NO
) " .. .,..;~-_:_..;...~_;;. ... ::.I..._ ..... _ •. __ • ___ 1 ,;;;___~_ ...':...__....!' ... . ___ ,..!_.._._. __
:2
o:
:
l' • .....J.'Z' ...6.L...J.2.L...J.'i.' ~ 54.' !.....15' .. !...-..33..~ ...!.-_.... .~ 0
7:317:377: 581: 427: 251: 229: 218: 233: 140: 70 : 77: 73: 97: 39: 11: 13: lO' 21 _---3. . . .5'.....5..• ]. ~_ .1>..... -4.l. ' ..-.,-!..... ~. ..J.: "'_ .... l" ".. " ..... , ., ... .. _ . • ...
5: ,
2: •
_~__ .!!._ .. _-::.!.. ...,_~.'!'__
1: 1: : 3169 : 0.96 . J.L • ____ .... '21L . Jl..JJ£. 6.. _ _ .... , '
f("':CIOIUIQ. 1+
:asbate Sorsogon i --l;-O-TAiJ~R----------~
r'
,. t : : ; :
n C D:
3: 7: 3 : 5: ~
2: -, :
16:
5; ~
6: 2: :
12: 1: :
5: ;
40: :
5: 11:
24: 6: ~
6: 2:
2: 4: 29: 19: 26: 1:
4: 6:
6:
5: 1: ':
3: :
6: 16: 13: 9: 1: 2: 1:
245 : 0.6S 69 0.19
3: : :
• ____ .._•. _._. ___ __ • _ _ _ __ __ __ __ __ __ ._--" _ _-<:: '_____ __ T:(,IOlJ NO. ! __ •.. _ _ _ ._.T ) : : : : : : 'l: _:._.___...!_. 1:;:_ ______r 1:
Cr -;----------··---····----f;---'f:---2:-i6-;--6:12-:---5-:0_ 40:--"24-:---'6: 2:-"4: 2: .---'_._.~,
:
::::
29;19:f:--6:~i6: -i3:
1:;:
11:
6: _ ,A._"'!'; ": 1: /,.:
6:
._ _ _.__
6:
6: 3: ':
__,_~_....A.____.
-: '): I I --.--: __
9-;--)-:-
:
--:
/~ : 0,01 _-L ____~.J._ ..O ......Q.Q.3.
249: 0,34
- • 7Q_:-. __O...Q9.. 0,23 0.06 1.32
~\GTON
NO.8
Davao (Prov.) Davaq City
C D C D
.
5: 1:
7: 1:
11:
101: 3:
27: 4:
5: 47: 5:
1:
4: 14: 20 : 21: 22: 17: 20: 10: 12: 2: -:
20:
4: 32: 5:
3: 29: ].
5: 10: 5: 5: -: 7: 2:
-:
-:
...
165
40
. -.
13 :
8: 24: 11: 11: 1: 1: 1:
-.
330 23
0.69
C '} v
I
~.
(
..•
,
..,
)
33 __• __ ~_.
_ _ _ ... __ . .
_
........ _ _ _ _ . . _ _
. . _ _ • • _ ...
'._.
- . , .. . . _ . _ _ _ . . . . .
_ _ _ _ ........ _ . . . . . . . . . . .
_ _ _ _ _ _ _ . • _ _ _ _ _ _ _ • _ _. _. . . . _
........ _ . . . _ _ _ .... __ ...... _ _ .... -"
.... _ _ _ . . __
.. . - .
. '.... _ . _ .. _ _ _ _
. . . . . . . . . . . . . _ _ _ _ ............ _ . _ _ _ - . . . . . . _ . _ . . . " " . _ _ ' ... .4 •• _ _
... _ _ _ _ _ _ _ _ ••. _ . _ _ ......... ~
••_ _
Total
: 3[\: 39: 40: 41: 42: 43: 44: 45 ; 46 : 47 : 48 : 49 : 50 ; 51 : 52 ; 1 : 2 : 3 : 4 : 5 : 6 : 7 : 8 ; 9 ; 10: 11: A~;usa-"l
i:'O
:
Rate
C D
Bt'tuan Ci t~r S· ri["e,o del Norte CotG.'~e,to .~ro".
C D
11; 2: •
C p
15: 2: 10; 0. U·
5: 2: 15:
26; C;.
6; -;
39;
3; 21: 7: 5; 17: 1:
C 1:
28: 5, . 2' 11; 17: -, 3: fl2: 1'" v' 1 t :
13 ; 34; 3 7 '
2: -: 22: 5; 30: 12: 93: 14:
Cok)'!2.to Cit,· 8 1.'.rigao del Snr
C n 'J
u
",.
49' ')
r C D (' 'J
J'
: isaids Oriental Ca[~a,'an
-.. -.
Q.
1:
de Oro
Gbgoog C5ty . ~"kic1:lOn -rol~!I.·j;~R·-
-, - -'0·:·'·----- - _ .. - -- - -- ---: A ..:..... _ _ _ .....
rr-Grr"l'T "0_._ 8 .. __ ~ ! __ ~.:.,;.:_.;'::..,l'... ., Jr:CIOi~ ..-...-.... 1<'0. .......... 1.'1:1::10
106:'·34: -6<j-:"'5Y;- I09-:-1s-572'lo;"23-f,'iio";'392-:3'67:40cj':111;79:'if6';--60':"4:F'41:" D · · · · , · , · 1 •______ ~_:.. L , ..__..... Jl' 22' 21' ~ 27' / ..r" 2(> 'i2' 47 1'" 20' 20' c' ' ~4')' ~~ ___ o .... _ _ ~.... _____:_ -.. ...':.. ... __ ........ __.-!.. __ A': __1) . ..::::.._c_ ;......!_.. __.... ~ ~~_. ____ ":0•• ' .!+ ~.~ ... _ ..... ,./. v•.•_~ .... ~~ ... '_._ .. -!.-& .• ___ ..-.2_~... _ ... '............. ____.~... _p. ..,:...._? ._ --.7' _._ _ ;,... ? .. £ ' ... ... & ••
T) C D , C ; D ':'
0, 3: 10; 15: 11: ,-' 1: 3: 6; 5: 11: 2; -: 2: 2: I: 1: -. -, 2: -, 10: 10: 5: 2: 1: 1: 6: Q. 7 • ~: 2: 2; - ; 1: 1; 1: 5 ; 4: - , 2: 20: 30: 27: 20; 10: 21: 24: 13; 25; 22: I; 2: 4; 10: 2; 5: 6: 1: 6: 5: G):1G9;222:297; 55: -~ 2[;: 4: 1: 10' 21.5: 24; 26: 2: -. -. .-', 33: 18 11 2; 4: 2: 4: 6: 3 : 0' . .. -, -. -'. 20; 3·:}; 44; 53: 37: 26: 39: 46: 14; 3; 3; .. '3. L, 13' • 3' 4' 13' u. ", 4'• - .. -. 3 '• 7" 37: 11; 2: 6; 1: 1: 7: 6: 1: -: 2; 1: -: 3: 4; 13, 14' 6: 4' 1; 16: -: 3 : 7: 1: 1: I: I: 2: -~ I: -: -: -; 1; -:
.
-.
14: -: 2: 1;
-
-, -,
-. •
-. -. -. -.
131 20 177 38 301 72 1077 121 1; 200
-;
4 65 13
0.64 0.10 1.99 0.43 1.43 0.31, 0,90 0.10 1 f .C;C 0.10 0.23, 0.05l 0.90 I. 0.10 0,05 0,02 0.005
0
~
2: -:
f6 7 3 1 1
3; 1;
1: ~ ~ ~ ~
:
:
:
~
~
~
~
;:
!
:
~
:
;
:
;
:
:
:
:
_:
~
'20":'-28'5'7":' '6.'0'1" _ _ .~ "....... ~
:
_;_
l'
4,01' C ))~ ~ _0" ... 0 .. ...,;;. • •
..
_-- --
7 C 1)
del Sur
1>ia.rawi City
31'.111
r£\11aO (l,el l orte T
Ilii'9.:1 CHy
C D C D C D C D
6: 254: 372: 235: 176: 64: . u. 3 ; 30: 134: 3.-'· 5: 4; ,\ , 13 ; 14: 9: 1: u· , -, 3: 1: 3 : 64; 166: 75:157; 6: 37: 12; 31; ",' -: I. 0 1; 4:. .... 2: 12: 4: 4: 4; 2; 1:
-.
-. S7;13C: -, u'
132; 36; 45: 20; 0. c' 7: u. , " 1: 20: 8: 10; 7: -:
6: -: 67, 6~: 33; 64~ 30; (; 36: 11; 10: 2; 30 1: 2$; 39: 7' 1: 5:
-.
f:
.
215: n. u. -,
5:
: 38: 3; 3; 4: ... -: 37: 30: -, 1; ~
1356 297 5 : 122
-. :
4
2.61 0.57 2.34 0.0[;
~
-,
U· 0.
.-'"
9;
-.
-,
-.
6: 1:
2:
L
-.
15: 1094 : 13 : 166 : 89 : 22 ; 43 4
3.11 0.47 0.37 0.09 0.66 0.06 ~/
I
'..,j ,
.'
f
I"~
(
c,
(
~
, I.
~
1
34 _._ ........ __ ., ....... _ .... _.-...-4- _ _ _ _ _ '._....._..........._ _,_..... _. ___ ..' ... __ ._..... _ ..... _._________._. ___ .. _ ........___________ •.-... _ ' ....._ ..... _._. ______. _______ ,... ~_,,_.
__ ._._._ ......... __ ........_. __ ..... __ ... __ ..... _ ................
_>_ ...
_
. . . . . . _ _ .... _ . , _ _ _ _
,~_4
ARZA
38: 3S: 40; 41: 42: 43: 44:456 C
46
47
4C;
49
50: 1; -,
51: 52 -:
1
2
J
4
5
6
7
~
Tota.l 9 2; 10; 11 110
R""to 0.23 0.01, 0.28 0.01 1.47 0.23 0.03
Z-oV·l':lO.:U1fD,
del Sur
r: C .!~.
Z,:.:-2bo~'.~_1"';a. Cit~r
R,silan City :. 'iSa['lj.s Q'.cidental OZ:l,'.liz
C
r 0 ., 1~
-:. 10: 56: 21+: -: 13: -: 2: 1: 10: 6: -~ 2; - ; -', ,3; 2; 11: 15: 8:. I' 2: 25: 55:. 30; 30; 23; 20: 22; 12; 25: J :. I: 2; 4: 2; 1: I: 4; 2=
5'
-, -.
-.
... : -. 13 ;
2:
-. ~
115 19 40 2
- -.
-.
-,
2; 2 ,', 1= - ; - :. ';a:"'l02,nza del c·Torte C 3' -:. -; 17' I,].; 24; 11; ___ ... ____ ,... ______ ._._ ... L .:. _.':__ .'. _ ..'__...',. __'. _ ...:. __ .:__.. _,__ ::.. __ ;____'" .. __ '. __. ,:. ,.. _.:. .__ . .:.. _ .. }; ...:. _1,:...":.'•• :.:••.5.'.. .5.:" • ..33.. _l,L TOTI'..L ""OR ( ; 6; 272: 465= 428: 287;268:322:27$;10e:1l9: 97:1}5:].02: 53: C 66' 'o~r;TO~T ..::~ no.,........... 7 _ .... __ 4.-.·.- ,:~_, n . ._ · · , ,· . " ':). ... _ 8" 1'1' 7'':)' 2:.2.-".:.-_ It;· JJ' c' 10' l''. _.";;:~!~"-::.;_::"'._~.:..-,;, ....~ __ . ___ :""_"",_,_~,,, ....... ~ . ___ <~_~ · ~ '4"-~'''''''_''_'''' ____ '~ __ '-'''''''· _____ ~''''''...........I'':: .... _ .... ,~~:.... .... ;:::t.....:-. .....77" , ..... ~ ___22' ....:_ ..... .,1_"-:.. ___ ... ...::.....2"" ..!-~....'_ .. !::;..G:..' __ -=--.~...... ...:i" ..;._ ...... : ... _, .•• C .. _ .. .......
2 -:.
14: 1,
4' 1 :.
-. (:
-.
-. - .
-.
-.
17:
247 39 6
.- .
7' 2:.
37; 0.74 5:. (\ .10 12: 15: 123 ; 0.41 ..-:~ .. ,::;_ ..• _15.• :_ ..0,.1':.5•. 9[L 54: 3272: 1.26 -' t;?':). 0 22_ .. ~ . .4' ~~__ ..-_ .. __ ~......_ L. --' .... "... _ ...........
:K:!J:..9I'; Fq, 2 Ga~-:_a:"'an
n :
c c
5: 1: -4... •• :: . . . . . .
10;
5:
22; 1/. ;
213; 17: 'r ... -: ......
ISi".'Jela
-. -. -. -. -, -. -. -. -.
-'--rp---;)T---~-- .,OT,.J '!OR
A-
-
_
.. _ .
- _ . - ••
2 ....-: .~.__ ,..::.. ...:.l!...,_:H(I ..~~!- __
'rcroY
--.0... _ _ • _ _........
~, ~ --<"", . . :::- .... -~. ~ . . 4:' ........!....-.. ::...... -- :-~ 5 10 . 22, 2<..>. -, -. 2. l . . , . . . . . . 1. 14'_ ••.•• 17'"......"":"_~ .•. ___~~ , '.. '..-_~_ . '-_,_ . ,... _ . . .~ I_ .... ~' ....._-";_,._~"' ___ ...~_._ ..... ..:__ ..... ' .~ ......_ ......... _ ..... _. ___' ____ ... ~. "", ... _-::~__ ._._ ... ~... _ ..... _ . .. :. ..... ~ .• "_ ... ' •• ~__ .... ' 5 .. :. ... ,_ ••.•• r.~ ,9 ...... : - . . . . . , .. \ .... _ -:'-- . . . . . . ... -.-. • • • • •.... ......... : .... ...
~j--,~- .. -..'- ... ~ C .
~-;-.-
'~
~~
~
_> . . -... ~. . . 4 ...._~_.o.-
< ...
2:
.-' : ...
..........
,0
•
to ......... ,.• _ .... .........
~ \, ..... ,..-:.
.
0.16 79 0,09 42 2 0.001. :'... : .....- ..... -:- ... -(',~.: . : .....-: . 10 13. 01. O,Ou , 5 . fir. , 2 'o~ 0 0.4. ~
1;
-.
13 : 5:
'('I.' ,
•. ,_..
..,c..... _
-4
..
_
.. ....
,
. - -GRjJj,ill- ------- --'c":" T~' -6Y:·-5~I; 123': 1"25 :510:'747: '1094";"'9'11 ;--c?i4:' -823' ;1302·:.·U;52'~ 'iTlo";'"'7'2"{:70Y;942 ;'9-ris'; "i2'5-:j·02;-iJ.'i, ;'i95';i'9-i :i2'5' .151;'"111-;146-7'5" ;'" o.'5Y' .. -.:'r9..:~\~ __ . _ ' _______ I-~ .".:_ ...2.'._ .1.I:__7.:,,)4 '_ J.1__ .7J:• .7.9_' , __~6.:...JlJ.;. .1.2.EJ. '. _95_:.. 2.3.3_:. ~2.0,,~. _l.tJ.4,;_ J.2.o. :JJ.2.'.1JA.'J.i4.:... .9_Q..:• .4..l..:..J..9. '. J).:_.2.7.:.._1.2.:. .l4.;, ....2.:. J.0_6A, ,:, . P.• 9.G.,. rhrch 26, 1962 J. J. liIZON, 'f.,D., ;-r.p,I!, C~:,ie:f
Disease Intelli:',ence Center
.)
~
..
<'
'" ,
~
( ..
r
-----
35
2. LOCALIZED OUTBREAKS - EPIDEMIOLOGICAL FEATURES - Presanted in the following sections are .sUDDarizations of najor o~tbreaks
in localized areas which have been investigoted by
the Disease Intelligence Center nod other field personnel. Included are the episodes that occurred in six different geographical c.rens widely scattered throughout the .country (Figure 6) and in the state oental hospital, which is the only institutio-
-,
nal outbreak of its kind recorded during this epideoic. Eophnsis have been laid, where possible, on observations relative to extent and ongnitude of outbreaks. oanner. of spread, and oode of trnnsoission and to sone extent, on host attributes and en-
\
From this presentation oaybe appreciated the brond spectrue of patterns and characteristics of the disease as oodified by existing .local conditions. 2.1. Manila - The first oases of Paracholera ElTor in Manila occurred on Septeober 22, 1961. These weretbree adults,
two cooing froD Pandncon district and a third frow Tondo. These were people who were closely associated with the ship dOCKS, by residence, occupation or facily contact. Following this initial occurrence, cases shortly thereafter appeared sporadically in nIl districts of the city - the distribution being characterized as spotty (Figure 7). The pe~ of the epidenic curve for the city was renched week nfter its start. ~ .--/
Oil
the fourth
FroD then on, it began to decline until
by the end of 1961 the incidence had reached what caybe consi-
\
FIGURE 6 PARACHOLERA EL TOR: PHILIPPINP..8 ¥!AJOR LOCALIZED EPIDE'~IC
19~1'-
SITES
1962 F' ;
,.../,/ I.... . '-, I
1 .~-' .......~ .. . /
, '! "
,.
~
-..... ;
,., ...
-;;-
nocos Sur '-___.;-,.\_ ./ ~
-...
)
(
...... :'
/
, •. '"oJ
\' ! . ",
.'
.11
..I i'\ ",
;,
.''JtI'- i
,_
....,
•
I
'. .' l· :
~"" va: . tOo,.
Masbate
/,.J
/ /'" ..J r,' , ,-'" " I Occidental l~egros
: \r
('.
I
I'v
I
"
I\. ......... '-, \ " /. ~ t
.::,:
\, \ \
Samar .
~. ~-
...J
Capiz
["
Y' ('
/;
~/
Zamboanga
.)
del Norte Ianao del Sur
Sulu
. ."
,
'" ,
.0.-"...."
0":
.--"\ •
\
I \ , \ () C)
( I
FIGURE 7: CHOIERA EL . R; iibNITIALCAsES ~ MANI ,1961 - 1962 ~ . SAN FRANCISCO -
DlS
l ~_:::==::::::=:::::--
to
~
/~~-
{ \
; I
tJ 0
/~~ ,f:.l'~ if
CI,' '!
i
•
TONDO
SHARBORc, " /
~-.!, NORTH f~f. ;.>:~. , v
() " ~ ~ ~.~~_J : S TA ~-.
S n•• Q/ AN '2~{)~ NICOLAS r:::-' __:f~ '.t/.,
jf! Jl. . ·-. . . .:::;,,,----.. . OOi.) 0 0 00 0 \, ._---:::::.... \ \0 !~; RUlf,S '> ~~ °0 00 D ,~---::::---r -==--:::...:- :ll::::-:-~. ="'--..\ \~/ i-.~ )' ~ -~' /I"\~,\. ~"- "~"f t- .. ~ .c,~"..~ :tf.=.:=:-....~ J·\~INONDO ~~·;~l~ // '\\ ~ -'--~~~::-~)·i ~A 4 I -. ---
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.., _.......",
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',\
.... ~ ./-;'::'7-'__ ~, ../ /'" 0. ......... e; 1- \.-- -~------___ -:::;...-' o('S"""LOC "'0 ____ -..;.,,-....i:N"."".·~-------::::::: ....... -1 _-~ -$._ f) '/u',n< (J • ~.-.______. ~.;-...... o~ d,,'Oo 0 () Ot:) 0 fJ ~ ~-.~
'-, I'
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gc:-~
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co
Dr.,'
\\
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a c:I
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MARIKINA
~--:::::::-.
'b
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SOUTH~) HARBOR
PORT ~AREA
•\ \~ ;.--:;:;" \,
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AOo
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SAN JUAN DEL MONI'E -
J'
00 ,. --~
c. '
\ J.ECrf-ND. 0- GASE~ -(/7- O~ATH5 It. • c"AS£$ POSITlIIE a,- OE-ATH po,;) TlVl!
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--"'':::;-_~ .. '
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~":.-;;~~~~-~----/1 \ \.!~~:;:~\.. ...-- 1\ Q[l'bo//O \\._---:;;:.-.:::-- ........ ~..-.~II \P'ASAY CIr-~ .. / / ::=::::::--~ ~ 1:-:;:::;-
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38
dered as endeoic level.: follows:
The distribution of cases by age is os
Table 4 Maniln, Philippines PARACHOLERA EL TOR CASES BY AGE 1961-1962
;r
& ,
Philippine Population Distribution 3.2% 10.2 10.9 10.7 23.0 16.1
Nuober of Cases 7 49 49 15 104 99 165 107 45 35 376
Percent Distribution of
CaNs 1% T T 2 15 15 25 15 T 6
.......
" £,-~
Less than 1 1 4 5 9 10 14 15 24
-
-
25 - 34 35 -44 45 54 55 - 64 65 &: Over
Total
10.7 7.5 4.2 3.4 99.9
-
100
An interesting observation was cade on the incidence of ga8tro~enteritis -.J
during the epideoic of
Porocboler~
El Tor in
Wanile.. The r~te
-.
of gastro-enteritis adoissions to the San Laza-
ro Hospital, the oain infectious disease hospital in the City, was analyzed by age group for a four-week period preceding the epidenic and n cocpnrnble period following its onset. The
following table shows ndoissions by week and by age groups!
I, t
.-
."":'
39 Table 5 GASTROENTERITIS ADMISSIONS BY WEEKS SAN LAZARO HOSPITAL, MANILA 1961 Week ~
-t-".
22.
36 . .2!l
~.
39 liO 41
42-
Total .2..2:27 40-42 163 198 21 123 204 71 39 159 123 $9
"Excess" Admissions Week 40-!;?
Under 1 51 1 - 4 66 62 5 - 9 0 10 10 - 14 6 4 15 - 24 14 14 6 25 - 34 13 35 - 44 8 4 45 - 54 g.; ,5 55 - 64 0 3 2 65 + 1 Total 167 169 Cholera Cases rNa- 0 nila area)
'9
53 70 11 4 11
14 11 8 2 0
184
61 83 21 25 12 13 42- 60 40 48 24 40 26 28 18 25 14 11 122 233 297 300 370
39 31 44 42 6JJ 60 15 19 25 4 10 14 7 37 57 9 40 35 6 25 25 0 18 16 0 3 13 0 J 8
42- 37
-40 25
6 5:1
1M 39 33 23 21 5
70 . 56
-1. 520
..l.l 967
120 90 66 49 51 30 447
-. I
....
0
0
3
59
55 113
93
0
261
261
The first reported cases of Para cholera E1 Tor occurred on September 22, near the end of the 38th week and, within a week, ca)
... '
..J
ses scattered throughout the greater Manila area were being recorded. Admissions for gastro-enteritis at the San tazaro Hospital Parach~lera
.-.,
(including those diagnosed later as
E1 Tor) rose sharp,.~
II
ly in the 39th week and continued to rise each week thereafter. If the gastro-enteritis admissions for the three weeks preceding the outbreak (weeks 35-37) and for a three-week period after the epidemic was reasonably developed (weeks 40-42-) were compared, it would appear that these were 86~
\I
(447) more gastro-enteritis
admissions during the latter three-wGek period. The increase in gastro-enteritis admissions is almost wholly among those 5 years
40 of age and over; no increase in admissions occurre6 among those groups under one year or 1 - 4 :Tears of ',ge, During weeks 40 to 42, 261 cases of ])arOl.cholera were reported fro:i the J,;;mila area essentlall;)T all of which were admitted to the San Lazaro Hospital. The calculated age distribution of these cases COj1lpared to the "excess" of r,astro-enteritis acl.r.d.ssions during this same period indicates the greatest relative excess of gastroenteritls (see table below) to be among those 5 to 34 years of age with an excess evident f'''r all. age groups except 21llOng
those u;:cler
-
5 years of age. Total ---"Excess" gastr~-(_40) enterl.tis ama, i!.•. Paracholera El 1 Tor casesi',
6 50
25
120
90
66
49
51
30
447
8
14
4
44
50
50
25
19
26l
(-1'< Calculated from age distribution of first 340 cases reported)
2.2. Iloc?s_2lt£ -
Iti the province of Iloc s our, there were
114 cases ,vi th 19 deaths irma 10 wunicipali ties frolH Eieptei'Lber 21, 1961 to Dece.,·ber 6, 1961. This represents an attack rate of 3Z.2 per 100,00G population and a iilortality rate of 5.1~
per 100,000 pop.,
with a case-fatality ratio of 16.67,;. Specimens for labor'i.t()ry confirraa tion were taken iroQ 37 cases anll 40.54;; of these were positive Lr the vibrio. The first case suspected to be paracholera E1 Tor was repor-
41 ted freif, the barrio of 'ra.mpoEo, Tagudin of ~eptember 21, 1961. This was a wan who had a hist, r~-
of having COLe frOl.l ".anila tw.
da~Ts
00he
iore the st;lrt of illness ane, eaten raw shriTaps the ciay before left the Clty. lio other ca.se developed in his f1l.J,d.l~T
cOillposec:, .f
10 members, but another resident of the barrio vlhose hO;'.se was 7()O hleters away fro!:l the first case caiile Gown with the c:isease four days after. The follmdng week (corresponding to the 39th calendar week) ; ;
..
,
9 cases with 3
dea<~hs
were rc:perted from the neighborint, barrios.
On the 40th week, 9 eases were again reported. Thereafter, the outbreak com~lete13r
subsiclec: in the coasta.l ba.rrios of the rmnlcipaliL~
ty of Taguclin. At this tll,le, a case was reported ta~r.
the town of Ban-
Fro!," then on, the dJ.sease spreac. to the neighborirl,-c, HUILtcipali-
ties. The epicleiillc curve for the whole provlnce shows too waves of hi;:h inciCi.ence; the first, represen"s the oictbreal; in the 9 Jaunicipalities, and the second and lesser wave represents the outbreak in the JiIt,hicipality of TaglJ.din alone. Ho ~electivity
for sex has been sho"'!1 sJ.nce males and females in the cases am: cieath:;. It has been ob-
were about equally
involvec~
served, though, that there were hlore deaths occ'-.rrll1g in the verJ young or the very old, espec:.aUy in cases associated ,lith conct;rrent affections of either the heart, liver or Iddneys.
11
l'
In the town
of Calbiga, 0i'. lJlar Pro-
vince, the epidel,Iic assumed the pattern of an explosive rather than a progressive type, su;;gestiq; a ~oj)h.,on-vehicle
transmission.
A total of 195 cases and 50 deaths were rece.rC:ed (l1,rir,g the eleTen days from i'lovember 21 to December 1, 1961. Table 6 i;L TOIl: C..·..3~S . ...:.ru i),;:,;i:.tllIS C.·L;.;IG;" SLi·iJ:i
PAR~CliUL.:t~: ..
November 12 - Deceluber 1, 1961
I"".
" /k,-
Date November 21
Cases 8
Death!!
22 ~
24 25 26 27
16 25 44 36 13 20 Ii 12
0 2 11
20 16 3 2 0 0
28
29 30 :December 1 Total
4
-~-195
0 0
50
The flrst cases were reported in Caronogsan, a barrio Sltua~eG..
at the LrlDl".th of the Calbiga River.
This river runs across '1\{0 days before the flrst
the town and er;]pties into Laqueda Sa:'.
cases occ;Jrred a freak typhoon lasting for an h012r passed the tOl'm, swelling up the Calbiga River. At the time of investigation, many
of the wells were not functioning; the water SOlirce was the river. 'l'he cases which sub4ieq1..:entl;y occurred were the Calblga Hiver. 'I'he high case-fatalitc' rc,tio may be attribu-ce( to the lack of intravenous fluids dv.ring the major portion of the epidemic. locatec~
primarily along
43
-"< •
2.4.
;Lan~__de;L.
J:l!!.r -
FollowinG cases of ?aracholera :::J.. Tor
in Davao City and Province and later in other areas of ;':;.},stern l'Undanao in 1'Iovember1 the dlsease erupted explosively in Lanao d"l Sur, ~"lestern
}.indanao, early in December 1961.
The [:;.rst known case oec'rred in the lareely ;·;oslem municipality of LUJ!!baba~raba.., on November 26. This tovm, situated, about 6
.....
ki10l.aeters east of' Lake Lanao, lies on the L\.IlJlbabayabc'.o ItLver. Shortly thereafter, explo-sive outbreaks occurred in this town and those of Tamparal 1 and Taraka lying downstream. Vibrio:::1 Tor iso-
lates were obtained on two occasions froll! this river.
Of 1,085
..
cases in the province between Noveuber 26 and JallUary 4, 955 (Q~j;o) were reported from these three towns and seven others lying on anG. near Lake Lan2,o within 20 kilometers oJ LUfilba':1a:rabao. The pattern of cases is sho~m
below:
Table 7 ? .cffi.;.CIIOhili.s. EL TOR: C.~0l::::' BY J-D2l lE,nuD Llii\:AO IJ}<;L ~llR 1-:(;V":;; b:Gh 29, 1961 - ,j ,;m.\RY 4, 1962
Area Lumbabay-abao Tamparan Taraka Nearby 'l'owns* Hest of prov. Total 1 16 46 7 63 4 15 22 1 9 30 34 45 22 115 l~
__ ..J.. 1
21 52 95 26
5 3 4 2 1 13 710 7 17 31 2 12 8 2 4 61 59 67 26 42 37 20 22 J-6 lQ. 13 ..J..
126 7 6 166 466
52 20 166 265 520 ~'1asin,
2.4 8.3 2.7 9·5 2.3 LUllibakan
'
I"i'
.
!±
DO
4 39147149212ill99 99 57 73 77 17
1085
* Hamain, Lolundo, l1arawi, Poona Bayabao, Bubong,
The emergency conditlons breaks pre~nt.ed·
engenclerec~ Wi.;S
b3T 'e;he explosive outestimated that (}nly 40~
complete reporting; .it
of the total cases were reported.
Juring this tlllle, 299 deaths oc-
curred principally amont, those refusing treatlaent and in those ,areas where it wa. impossible.~r too precarious to establish h~Tdration centers. In Ta.l1lparan "lhere a h:~dr2.tion
center was situated, 27 of
217 Cied, 'lhile in Taraka where none was poSSible, 127 out of 166 reported cases ciied. The trans;cw.ssion of infection by water was suggested b~r
the in
explosiveness of the outbreaks; inorcinately high attack rates
only a. few tm'ffisj and within these municipalities, disproportionately high r2.tes awn[. the bn.rrios alonE the rlver. Introduction of the eelsease by one or both of two possible means was suggested. One possibility is through the merchants who
are especially 2ctive in 'che involveel area antl who travel frequently to DaVilo. ,lith few toilet facilities in the area, stream pol-
lution is cert<"in.:I'he secone;' lJOssibility involved the transport of the boel:" of a victirll cf the (hsease from Davao to for burial on j'~overjlber Lumba.bayab;~
23.
'l'he Sultan of Cadayanon died in Davao and was transported to LurclbabaYD.bao where be' custo,;, the bod:! was washed in the rlver and the intestlnal contents COllililOnly ties use(~ e:;~pressEJ(l
prior to burial. The river is
for bathing, drinking, ..mshing and for toilet facili-
a,~ong
those living near it.
The first case occl..'_rred in Lumbabayabao on l'Jovel!lber 26, the second on December 1 in Taraka and within five days, ."G.
42
additional
45 cases had been reported in these to,m~
and in Taldparan.
2.5.
~~
- Illustrative of the pattern of disease spread in
the Loslem areas of !'d.nclanao and SuJ.u provinces is prvvided by the follo,vine: observations oi epideL;Qologists of the Disease Intelligen.e Center from a brief vlsit to the Seit Lake Area, Sulu. The first Paracholera El Tor case in the nnmicipality of Seit L2.ke, Sulu, occL'rred on 0eceuber 27, 1961. This was a Losleul quack doctor (native ",eciClne-liJB.l1), 62 years of age, who went to nearby ;·'ata Island to treat cases of cholera there. He retnrned on
ueceiIlber 27, 1961 to Seit Lake end that same da~T, he had lIylllpto;ns of diarrhea Gnd volllitlng... he refL'.sed. He was advised to go to a hospital but
Instead, he called a ;-Dsle;.: "panday" (masseuse), a The "panda;)," developed SY;,lptordS that same nibht
65-year old woman. and both ~ied
the folloVQTIG day.
Following native c"stora, relatives vislted and kissed the dead. The ciead were bat.hed in the house and then buried. All the
8 relatlves who vlsitec.. ane: kissed the dead bodies contracted the d.isease. Three were brou~_ht
tv the hospital anel recovered, while clied. 1:0 information as tc source
the 5 who were not
hospitalizec~,
of food and water sl:pply was glven. Of those ''I'ilo carried the dead to the grave, I) got sick. Two only were hospitalized and recovered; four ctJ.ed. Seven da:rs after the burial, there was a feast. Approxim.ately 300 ate and of thelll, 35 g0t sici~.
..... r -
These 35 came fro;" other bar-
rios, and as a result, 6 additional barrios in Seit Lake bec~ile involved.
2.~. J:..:'llJ1boanga· .del Eorte - One huno.red forty nine cases with
27 deaths from Paracholera li:l Tor ol'c'-lrreu in Zar·.lboanc,a del in the months of Januar;-,r and l!:ebruarrJ 1962. these cases were confirmed by the laboratory. tered throughout
i'Jor'~e
Twenty two percent of The .ases were scat-
9 municipalicles wlth the highest attack rates in
the municipali:.ies of Jipolog and Uapitan ami along the main seacoast. road. The poblacions had cOlllparativel:;r lower attack rates
than the barrios. rift:'" seven percent of the cases were lilales and The age dlstrlbut.lon 43;~
were fe-
0:::
cases 'o-ras not to<, (LIferent frow.
that of the general population witII the exception of slightly higher perce"tages of cases in the 5 to 9 and 30 to 40-year rl[je grou.ps. The socrce 0:;'
the introdu('tion oi paracholcra into Zaraboange. The epi<ierrL"lc probab17 began with
del lior-te could not be icie;;tifieG..
occasional scottered cases in Janu2.r,)r and reached its peak b:r the [;Jidcl~e
of FebrL,d.Ij',
C;,ses were still being reported in
earl~r
c,rch
2.t the rate of 1 per (ay.
Lost 01 the cases occurred in the lower po~)t,latior,
income Groups though the ch;lracterlstics oi::' the
Kith
clinical (i:i.sease may not hilve been ve:r:! cllfferent from the general population. Twenty hetcseholds h,~c
multiple cases with all cases ill each no large CO;.U:lOn-S01;,rce
household occl'rring \'Jithin a 6-da:r period.
cl:tbreal;:s Here id.entified, am: no om:'! fooe' or g-everage was shmm to have 2.ccount8l.: for a I~JaJorlt:7
of cases.
Intensive case investi-
gation of over 50 cases falle, to revea:L the exact number of traIlSmission of the disease in any ca.se,
47
2.7. National Mental Hospital - An Institutional Outbreak \ihile the paracholera El Tor epidemic in the metropolitan area ~~nila
of
was already well on tho wane, the disease hit the National
Mental Hospital, the only state mental institution in the country, located in Mandaluyong, Rizal, six kilometers from the city. Inten-
sive studies, carried out by the Disease Intelligence Center epidemiologists in cooperation with the National Hental Hospital Dispensary staff revealed epidemiological observations which are summarized as follows: Built in two stages, in 1928 and 1946, the hospital is comprised of 76 buildings dispersed over a 64-hectare lot. The hospi-
....
tal is densely overcrowded with 6,627 patients occupying space designed for 2,000. Hany of the 1521 employcos at the hospital occupy Located in the Ladst of the mental hos-
residences in the compound.
pital patient facilities, identical and ll.djll.cont to the large pavilion 2, is the National Orthopudic Uospital which serves both as an orthopedic hospital and a rehabilit;"t::'_:. center for those with bone injuries or cerebral palsy. Four hundred patEnts at the latter Approximately 80% of the .J
hospital are cared for by 593 employees.
patients and staff at the Mental Hospital had been immunized ,·:ithin a 3-month period prior to the epidemic. The first cases, four in all, occurred on November 18, twelve occurred on the~
succeeding day, and 76 between November 20 and 22,
After two weekS, the outbreak had involved a total of 172 cases. Plotted by day of onset, the 172 cases describe a series of three overlapping epidemic w~ves,
each less marked than the one pre-
4B ceding (Fig. B). The first and most major shows a peak on November 21 (27 cases), the socond on November 26 (15 cases), and the third on November 29 (9 cases). FIGURE 8
NATIONAL MENTAL HOSPITAL PARACHOIERA EL TOR CASES BY DATES OF ONSET NOVEMBER 18 -DECEMBER 1,1961
30 25
.........
,
C 20 A 15
r--
r-r--
r-r0-
...--
S
1O E
S
5 n.
n
22 D
_r--
r-25 S
18 19 20 21 NOVEi1BER
23 A
24 Y
26
27
28
29
n
30
1
DECEMBER
An additional 112 cases scattered over a seven-week period following this explosive onset. \
In all, the outbreak took 10 weeks
to ran its full course and a total of B24 cases with 4 deaths were recorded (Fig. 9). This represents a morbidity rate of 49.73 per
thousand and a mortality rate of 0.70 per thousand for both sexes. The case-fatality ratio is only 1.41%.
49 FIGURE N U M
9
140 120 100 80 60 40 20 0
NATIONAL I·!ENTAL HOSPITAL PARlI.CHOLERl. EL TOR CloSES BY '"lEEKS
1961 - 1962
B E R
0 F
c A S E S
46 47
48
49 H E
50 51 E
52
1
2
K S
3
Verification of diagnosis of the first cases were made by bacteriological exandnations of ructal swabs taken at random among the cases. Results showed positive isolates from 75% of cases for
tho first two weeks of the outbreak and 25% for the succeeding two weeks more. The first four cases, on ]l)ovcJ:lbcr 18, wore from a male resident pavilion. On the following day, caseS were noted in two sepa.U
rate pavilions and two of the cottage units and, by the fifth day, cases had been reported from each of the six major rcsident pavilions, six of tho 10 cottage units and two of the smaller resident buildings,
,
Cases by resident unit are shown in Table B, both for the initial five-day period of the epidemic and for the epidemic as a whole. Initially involved units show the highest rates for the
total course of the epider.dc; three of the sevon units without i-
50 nitial cases---experi enc~JJ.O.-cases-..duringthe-remai.nder of -the epidemic. The explosiveness of the epidemic, the dispersion of caSt:lS throughout the many hospital units between which patients have little or no contact suggests an initial dissemination by some common vehicle. Hater, supplied to tho N(mtal Hospital, is distributed by a
common system to the Orthopedic Hospital and is consumed by employees of the National Mental Hospital. Neither patients nor emplo-
yoes at the Orthopedic Hospital nor employees at th(.: hental Hospital exper:ie nced cases. Inspection of the plumbine and bacteriologic and
chlorine studies of the water supply carried out on November 21 by l-1ajor Thomas Ostrom, Walter Reed Army Institute of Research, revealed no evident defects or prob10ms. Forty-five cultures of kitchen employees takt:ln on Novt:lmber 24 revealed that two of the ten cooks in the kitchen were carriers of Paracholora ~l
Tor ; no others wore positive. Further investigation
of the cooks revealed that no caSeS had occurred among tht:lir families
,-.. \
or in their immediate neighborhoods.
Host probable was thnt tht:l
cooks had either served to infect sor.le food or had themselves been infected by the suspected responsible food item. Idcmtification of the suspect food item by mGans of the classic <)pidc);liologic o.pprouch had to be abandoned because of the disturbed state of so uany of tho putients. necessary. Since the initio.l four cases duvelopod between 12:30 pm and midnight on November 18th and assuning a nlinimal incubation period
An indirect upproach was
51 for cholera of 12 to 21 hours, the meal at which the food was served, necessarily was either tho noon or evening meal of November 17th. The foods served at each of the mU111s were; prepared and delivered on the same day as it used to be. BE;cause of limited storage
space in the kitchen areas, food preparation for each meal is begun four hours or less before it is served. Little opportunity there-
>,
fore, is present for organisms to multiply sufficiently in the food even if introduced by a carrier. The six items on the menu for tho noon and evening meals were as follows: ",.
Noon Meal 1. Beef - boiled until soft 2. Pans it miki 3. Banana ~.
Evening Meal 1. Diningding Smoked tinapa-baked 3. Lady finger cookies
Of the above six items, tho smoked tinapa, a kind of native fish, has been incriminated as the most probable vehicle of infoction.
52
Table 8 PAhACHCUl(A &:, TOH:CAb&S BY :0;:; I;)ENCE UNIT NATIvNAL ,"iEr~TAL HOSPITAL 1961-1962
De~igr:!..ed
g~~~~
~c_c.~s;J:
Actual ----
G2..~e~
Cases Nov. 18 - 22 35 17 3 1>~ 1 0
(~)
Tot_al CRr'.es Cm;es 88
C~)
(Nov. 21)
........ ... /It-
Pavillon Pavillon Pavilibon Pavillon PavilIon PavilIon Cottage
2 400 100 3 100 4 300 5 6?riv200 7 1 2 J 4 5 b
2258 511 1.,84
148':: 184 n;FIRi,A;cY 26 137 173 173 165
1.6 3.3 0.6 1.2 0.5 LFIc'JHY
66 8 70
5 1 1 1 0
3.9 12.9 1.7 1,.7 2.7 1.2 0.7 1 .~
0
u ()
0
66 54 59 109 90 53 56 69 23 170
1 4 2
? 8
.-
9 10 .
3 4 1 0
0.6 5.9 3.7 5.1 3.7 1.1
0 3 7 6
5 10 2 1 1 1 0 ~3
10.3 11. 1 g.5 9.2 2.2 1.9 1.8
,-'"
........
Chinese PavilIon Inner ;l1e11 Pay • 2
, .O'1len i s Aux.
3 m{~.g.
0 1 0 2 0
1.4 1.2
1.4 4.7
"~
-,-,"ployees
1521
0
53
3. HOST ATTRIBUTES 3.1. Age and Sex distribution 88 deaths in the Manila area, as ble ~aybe
In a series of 720 cases and noted in the teble below (Ta-
9), the age-specific attack rates per 100,000 pop. are definitely'
higher in the age groups cbove 25 years (Fig. 10), while the agespecific mortality rates are highest in the 65 years and over age group, and lowest in tho youngest age group affucted (1-4 years) (Fig. 11). Table 9 PARACHOLERA EL TOR: Ao:::1; 3P.ECIFIC CASE (Por 100,000 pop.) Manila !~€a, 1961-1962 Age Group Und.3r 1 1 - 4 5 - 9 10 - 14 15 - 24 25 - 34 35 - 44 45 - 54 55 - 64 65 +
....
&
DEATH RNI'ES
-3 55 .60 ~7
Cases Number Rate 1.7 10.06 10.28 4.72 9.17 16.60 20.82 26.86 25.98 17.95
DGaths Number Rate
;'
,
.91 2.57 1.39 .97 .92 1.56 2.48 3.14 7.85
113 144 120 100 58 32
15 8 12 8 9 10 7 14
Available data from several aroas in Luzon, the Visayas and llindaneo arc shown in tabulations below, Tables 10-A and B. by age and tt~
Cases
percentage age distribution for each area are shown
in comparison with the percentage age distribution of the total Philippine population.
FIGURE
10
PARACHOLERA EL TOR: AGE-SPECIFIC CASE RATES PER 100,000, MANlul. AREA
1961 - 1962 30 -
25
C A
20
S E
15
.
R A T E
10
5
30
35
40
.
, 4
YEA R S
o
F
AGE
t
.~
(,
I.'
·'1
(
.<
'{I
FIGURE
11
PARACHOLEM EL TOR: AGE-SPECIFIC DEATH RATES
PER 100,000, ~!AlnLA. AREA 1961 - 1962 8.0 +
7.0 6.0 D }~
A T H
5.0 4.0
R
A T E
3.0 2.0
1.0
r--
, L_
o
5
10
15 20
25
30 35
40
45
50 55 OF
60 AGE
65
70
75 30
35 90
YEARS
"'
~
(F
"~
""j
(~
,~
(
56 Table 10-A PARACHOLER..\ EL TOR: CASES BY AGE SEVER,'J, AREJ~S, PHILIPPINES 1961 - 1962 Luzon Mindanao Visalas I y Manila !if l' il ~ 11ocos Sur Capiz Dumaguete Davi1.o Surigao del
~
y
§f ~te.
Under 1 1 - 4 5 - 9 10 - 14 15 - 24 25 - 34 35 - 44 45 - 54 55 - 64 65 + Total
:3 55 60 27 113 114 120 108 58 32 720
) )
4 18 13 7 16
0 41 24 l2
)---- 56 ) .*-,
l
49 91 54 37 16
...!2... 114 343
12 11 4 14 10 12 9 1 _4_ 30
:3
0 4 11 1 16 20 17 19 11
0 5 16 12 21 13 22 15 13
-1 102
--.L 131
Table 10-B e.J\.RACHOLEfu~ EL TOR: CASES BY AGE PERCEN'i'"'DISTRIBUTION, SEVEfuiL AREAS, PHILIPPINES 1961-1962
1"""•. \
Age Under 1 1 - 4 10 15 25 35 45 14 24 34 44 54 55 - 69 65+ 5 -
---
9
Population Distribution 3.2 10.2 10.9 10.7 23.1 16.1 10.7 7.5 4.2
Phi1i~e
Manila
Z.4
Mindanao Surigao ~ 11ocos Sur Capiz Dumaguete Davao del Nte. 0.42 3.51 0 4 0 0 7.64 15.79 12 15 4 4 8.33 11.40 7 14 11 12 3.75 6.14 3 3 1 9 15.69 14.04 14 18 16 16 20.(0) 27 12 19 14 16.67) 16 15 17 17 5.00)---49.12 11 11 18 11 8.06) 5 1 11 10 4.44) 6 5 3 7
~
Vis1llas
!I Y 2!
£I
Disease Inte11igen~e Center Staff Dr. Joaca,uih T~lI11ayo, A8Si:~b.;,t rHO, nocos C".:.r . Dr. Julio Valera, Disease Intelligence Center ~ Dr. George Buan, Director of Research, Sjlljman University Hospital and Dr. Pio Lauengco, Provincial Health Officer, Negros Oriental 5/ Dr. Cipriano Garcia, Provincial Health Officer, Davao Dr. L. D. Carlota, Provincial Health Officer, Surigao del Norte
57 The percent distribution of cases by age, while varying in different areas is remarkably high in the 15 years and above age group, ranging from 62% to 84%. In the Manila area and in Eastern Mindanao represented by
Davao and Surigao del Norte, the percent distribution of cases in the under 5 years age groups, are
B%
and 4%, respectively which are
relatively low, compared to those of 1locos Sur, Capiz and Dumaguete, where the percent distribution are 19.3%, 12% and 19%, respectively, for the same age groups. The percentage distribution of
,
.
the total population at risk in these age groups (under 5 years) is 13.4%. There is reason to believe that the Mindanao figures ~fuslim
would change significantly if Lanao and 9ulu (the
areas)
figures were available, since multiple cases in households were commonly observed in these areas. These differences in age distribution patterQs may be more of differences in exposure potential, customs, eating habits, level of he~th
education, and environmental sanitary condition
and in part, to reporting of more or less severe cases nL10ng those over 55 years of age, a relative paucity of cases 0,~ng
those
aged 10 to 24 years and somewhat variable factors in the other age groups rather than due to intrinsic factors. Estimates of age specific case-fatality ratios made for Capiz on 343 cases and 41 deiC.ths and in and around Hanila, early in the courSe of the epideLuc, on 371 cases and 62 deaths are shown below:
~.
58 Table '.Q) Pl.RACHOLERA EL TOR: AGE SPECIFIC CASE FATALITY RATIOS
MANILA AND CAPIZ 1961-1962 !£,!:. Under 1 1 - 4 5 - '9 10- 14 15 - 24 25 - 34 35 - 44 45 - 54 55 - 64 65+ Manila Total Capiz Cases Deaths Cases Deaths Cases Deaths %Fatality 1 20 26 6 73 83 93 91 0 5 8 0 11
5 7 8
'\
-l!L 343
44
6
0 41 24 12 49 91 54 37 16 471
0 9 6 1 5 6 4 7 0 62
1 61 50 18 174 147 128 60 814
0
14 14
lU
16 11 11
1
15 6
23 28 6 13 6 8 12 10 ~
.l:&.. ..li. 41
..1... 2L
.l:L 103
12.7
For those groups between 10 and 64 years, cnse-fatality ratios are uniform, ranging ~etween
6 and 12%. Significantly higher
ratios are obtained for those under ten and for those 65 years of age and older. Previous studies during epidemics of cholera have
demonstrated similarly higher case-fatality ratios in these age groups. Differences between the occurrence of cases among males and ,
females have generally not been significant at any age.
However,
figures for the Manila area and Cnpiz both show slightly more males than females cases, Table 12 PARACHOIERA EL TOR: Ci\.SES BY SEX MANILA AREA & CAPIZ 1961-1962 Manila Area Capiz CD-ses Deaths Cases Deaths Numb~ Number 01... Number .1... Number .L 178 51.90 26 6).41 421 53.63 49 55.68 ~ 46.37 2.2. 44.32 165 ~ ~ 36.59 785 100 88 100 100 100 41 343
~
Male Female Total
59 This observation may ~gain
be attributed,as in the age
distribution differences in areas compared, to slightly more expo sure risk to a new infection of the male adults p~icularly
the laboring class who work outside most often in insanitary surrounding and unhygienic. conditions, Presuming that the infection
has been newly seeded in the enTironment, the lower the leyel of health education of the community and the poorer the environmental condition, the more diffuse the infection would be both in the household and in the con~unity
and therefore, the greater the
chance of the younger age group and the female group to be exposed. Admittedly, the environmental conditions and the lqvel of health education in some areas in 110cos Sur, Capiz, Dumaguete City and in the MosleD. areas in Mindanao llild Sulu <,xe relatively poorer and lower than in the IvIwila area wd D.:.vao City.
3.2. Occupational Incidence: Socio-economic Groups and Nutritional Status - Of more than seven hundred cases investigated in and around Manila area, a considerable portion or about 30.3% were jobless and 25.3% were plain housewives and housekeepers; 8.2% were laborers, 6.6% fishermen, 3.~%
.....
students, llild the rest The stable, well
had significantly varied odd, low-income jobs.
situated, well dressed, well nourished classes of the population, surprisingly seem to have escaped the disease, so much so, that some workers suspect that, besides exposure potential of these groups of people due to poor sanitation of the environment and poor hygienic habits, other predisposing factors might be playing
" I' , II
"
60 roles in the causation of the disease, such as fatigue and certain nutritional status of these individuals. This suspicion,
of course, although worth pursuing, is at present without basis, and observations made in the National Mental Hospital outbreak seems to strongly favor the assumption that exposure risk rather than intrinsic factors are at work in the apparent lower socioeconomic group selectivity of the disease. In that outbreak,
,.... ! , I. l" .I.
284 cases developed among the more than 6000 mentally ill patients, while none got sick among the more than 1500 staff personnel of the hospital and the dispensary. and
,
Taken at surface
value, this observation could easily be interpreted as group selectivity of the disease but detailed investigation revealed and strongly indicated that it could be more of differences of the two groups in exposure potential to the vehicle of transmission all!i: the disease agent. 3.3. Immunization status - Of the 661 cases inveetigated in and around Manila, 167 or 25% had been adequately vaccinated
,
with cholera vaccine, within six months of the disease
onset~
And
among the 80 Dumaguete cases, 23 or mhad similarly been vaccinated. These percentages correspond roughly to the proportions
of persons believed vaccinated in the population group from which most cases occur. The total per cent of vaccinated popUlation
for selected provinces in the Manila area where the first cases occurred on the 38th and 39th weeks were only 12.44 and 15.07 per cent respectively. As priorities were followed in vaccina-
61 tion, the lower economic groups of the population were with somewhat higher percentag~
Incideut&llYI it
i~
ic theee
~ups;
as;
6hown previously, where most of the cases occurred. No information regarding the severity of the disease among the vaccinated and non-vaccinated is presently available. The
case-fatality rates computed on these two groups, while slightly more for the non-vaccinated, however, has not been shown to be significantly different. ~
/
~
J " ii
~i " " II II " II "
62 4. ENVIRONMENTAL FACTORS _ With this particular disease, as with any other gastrointestinal disease, a major role is expected to be played by the environment in the extent of transmission. i~
In this regard a review of the status of the gene-
ral environmental sanitation condition of the country, with particular emphasis on water supply, food and dietary habits, waste disposal and extrinsic factors such as temperature, humidity and
environmental factors and their variations, with the occurrence of cases.
4.1. Geographical Distribution of Cases - It will be noted on Fig. 12, that the infected areas were mainly coastal. , While
it has to be admitted that the coastal areas are more populated than the interior, especially of island~yet,
a comparison of
the attack rates in coastal and in-land towns in the same province, show higher rates in the former. p~1~ularly
This fact has been
observed in the primary outbreak in Manila and nears~~-foods
,
by areas, and is in line with the hypothesis of
serving
as the probable vehicle of transmission in these areas. 4~2.
Meteorological factors -
Data on rainfall, tempera-
ture and relative humidity during the week of onset and the preceding week are available from some affected provinces and cities. Some of the readings, however, most probably were not made at the exact locality where the disease oocurred, which fact limits the validi ty of these data to [1.
large extent.
FIGURE 12 FHILIPPINF,s PARACHOL."RA ."EL TOR: INFECTED AREAS
63
'1961 ':;;~962
o no " 0
I/JfiJ> 0°
64 Rainfall - Data from 54 affected provinces and cities showed that the daily rainfall ranged from 0 to 5 inches" during the week of onset, with a great majority having less than 1 inch of rain a day. During the week preceding the onset, the amount
of rainfall was practically the sume. Temperature - Minimum temperatures during the week of onset in 41 affected areas with available data ranged from 17 to
23 degrees Centigrade with a median of 21 degrees, while maximum temperature readings ranged from 2B to 36 degrees Centigrade with a median of 32 degrees. did not differ significantly. Relative humidity data for 2B areas showed n range of 74 to 92% and a median of BO - B4%. Although from the analysis made above, a general statement can be made that no unusual climatic conditions were observed immediately prior to and during the onset of the disease in an area; and no relationship was apparent between the variations in such meteorological factors as rainfall, temperature and relative humidity and the magnitude of the outbreak in ~
Readings during the preceding week
area, clo-
ser;8.crutiq. (If .'data in the Mimila area, revealed that on September 21st, a day prior to the appearance of the first paracholera El Tor cases, the rainfall was 3.65 inches and on the 22nd, 2.62 inches. These were two days of heaviest rainfall experienced
during that month. In Calbiga, Sarner, it was recalled by the residents that
a day before the first cases in the explosive outbreak started, ."'-
65 a freck typhoon occurred.
4.3. Water Supply - Only about 41% of the Philippine population are provided with a potable water supply. This includes the
people living in Hamla and suburbs estima.ted nt about 2,600,000 or 9% of the total popula.tion, practically all of whon safe water supply. h~ve
a
For the rest of the country, only ccbout
<l.4%
have a safe water supply which is obtained from 836 water systems, 16,932 artesian wells and 1,938 improved springs. The rest have
to depend on dug wells, unprotected springs, rivers and creeks, and rain for their water needs. Generally, cities, towns and big
barrios have safe water supplies but mAnY ba.rrios do not have any.
The NWSA estimates that 50,000 more wells <.'.re necessary, a.t the '.,1
rate of one well for every 250 people, with the wells at least 300 meters apC'.rt, to provide everybody with sa.fe water. Of 661 cases of Paracholera El Tor investigated in Manila and surrounding areas, 437 or 66% had piped water supply. Of
these, 55 or 12.6% obtained their water direct from the faucet, the rest storing their water in difforent kinds of containers before use. Of those without piped water supply, the sources I
were dug wells with or without pumps, springs, rnin and surface water, and the water by necessity had to be fetched and stored. The possibility of water getting contaminated and acting as a vehicle in the transmission of infection is great except in the few who obtnin their water directly from the faucet. The pos-
sibility of contaminntion exists even if the water source is
-l. .,
66 safe, when the water has to be fetched and stored. The distribution of Paracholcra El Tor cases in Manila and suburbs , according to water supply is shown below: Table 13 PARACHOLERA EL TOR: CASES AB .. TO WATER SUPPLY MANILA & SUBURBS 1961-1962 Water Supply Number of Cases 367 70 182 25 9 1 7 661 Percent 55.5 10.6 27.5 3.8 1.4 0.15 1.05
.-.. '\
:.
Piped Public (Heighbors piped) Deep pump well Shallow Dug well Spring Rain Surface water Total
100%
Many communities which had big outbreaks of Paracholera El Tor did not have safe water supplies and the possibility of their water being contaminated was consequently greater, This was pro-
ven on several occasions by the isolation of the El Tor vibrio from water samples obtained from infected areas / Get[ ks_ Taraka and Lalabuan rivers in Lanao del Sur; sea water in Bo. Rawis, Laoang, Samar; water from the wharf at Catbalogan, Samar; a dug well in Bo. Lublub, Dumangas, Iloilo; river water from Surigao del Norte, and a deep well in Taguig , Rizal. From the data obtained in the study Dumangas, Iloilo, ~ ~orrelation ~t
Barrio Lublub,
of 2ll positive survey swabs
plus hospital cases from the study area with water supplies used for drinking, was attempted.
67 Well DW 1 DW 3 DW 4 DW 5 DW 8 DW 9 DW 12 * DW 13 PP 1 Rainwater
No. Positives 1 2 0 0 1 0 2 3
Popuhtion
AR!lOO
14 15 43 16 2 23 5 3
6 4
7.1 13.3 14 25 0 0 0 3.3 7
62
31
9.7
Note: DW - Dug Well PP - Pitcher punp well -l~
N;my other persons outside the survey arei1 used this well precluding calculation of ~ re21istic attack rate. f~lies h~d
Many of the
dual
w~tGr
supplies, one for
drinking, and another for cooking and other domestic uses, PP 1 is a well-constructed lined well 20 foet deep with form count (MPN 190). ~
low coli-
In contrast, the dug wells arc not much h~ve
more than holes in the ground rmd
coliform counts in excess TWo of the sur-
of MPN 11,000 and often in excess of 110,000.
vey positives occurred Qffiong users of PP1, while 14 occurred ~ong
users of dug wells.
There is
~
slight
indic~tion
that a
/
good water supply Day docre:J.se the prevn.lence of El Tor =ong a populQtion, but the data consist of very statistical significance improbable. sm,~
numbers making
4.4. Food Supply -
The typical Filipino diet consists
of rice and either fish or vegetables depending on the region and the people's occupation. In coastal regions where fishing
68 is 1'.
major occupation, fish and other sea foods are usual. items
in the diet; while in inlnnd towns nnd barrios where the people are mostly farr~ers,
the food is usually rice and
.~getables
.:.1-
though occasionnlly they D.ny Also hD.ve fish.
1-1co.t including poul-
try is less conunonly included in the usunl meal except among the higher socio-economic groups. The use of fresh dairy products as a food item is negligible. Informction on the foods t~en
prior to onset of illness is
2.vt\ilable for 504 investigilted Paracholera ct\ses. These are summarized below: Tilble 14 PHILIPPINES PARACHOLERA EL TOR : CASES BY FOOD ITEMS
1961 - 1961 Foods Taken Fish and other seafoods (Sea foods eaten raw' Vegetables Meat Fruits II Bagoongll other Foods .L
No. of C[tses
Relative Freguencl of Association
,
373 55 121 97 75 58 91
74% 10.9%) 24% 19.2% 14.9% 11.5% 18%
Almost 3/4 of the investigated cases gave a history of having eaten fish or other seafood on the day or D.
few days previous
to the onset of the illness, which probably represents the proportion of the population eating this kind of food. However, an interesting information is the almost 11% who took fish, small shrimps or other sea foods raw. A considerable number of the earlier cases ,
..
~
69 of P~r~cholerc.
El Tor in Hc.niLl. ".nd suburbs as well ,'.s in T.lCIny
areas in the Visayas gc.ve the history of eating raw senfoods,This observation drew c.ttention to tho possibility of fish ~d
other
seafoods acting ns vehicle in the trc.nsLlission of the disease. Attemps to isolate tho El Tor vibrio frou fish and other seafoods were IJ.c.do on hundreds of spec inens, but all gave negative results.
4.5 Waste Disposal - Tho Division of tion of the Bureau of HeLuth
~nvironmental
Sanita-
Servicos ostllUc.tes that 54% of the
,
populntion have simitary facilities for excreta disposal consisting of pit priVies, septic tanks, "'.nd a sewerage system. The only sewerage system in the country serves parts of Hanila ;.md
Quezon City. The sewage collected is discharged raw into Manila Bay at a point about 3/4 mile beyond the breakwater or more than a mile from the shore .~t
Tondo, of the facilities for the
Pit privies constitute the bulk
disposal od excreta particularly outside the Manila area, although there are septic system~. t~s
:in cities and bigger towns which have water /
It has been observed that almost all of the cases of Paracholera El Tor occurred among people living in poor environments without sanitary facilities for excreta disposal. Undoubtedly this type of environmental condition contributed tremendously to the dissemination of the infection, either directly to persons or indirectly through flies ilnd other insects, food or water to which the wastes may eventUally find their way,
70 But the presence of Q
sewerage system, septic tanks or pit
privy does not guarantee that the El Tor vibri.o will be totally kept out of circulation. i.s f.lontioned above the sewage collected by the sewerage system is discharged into Haml2. B2.y without treatment. Effluents from septic tanks generally discharged into street ditches ~d
gutters, while pit privios may permit the en-
try of flies and other insects or the excreta Day seep into nearby dug wells.
-" ,
71
5.
TRANSNISSION OF THE DISEASE
5.L. Source of Infection - ,.lthough without concrete evidence, denic is following curred in Manila. it is believed that the current Paracholera El Tor epi-
of foreign rather than indigenous origin, b':sed on the observations and ~plications: 1) The index cases oc~mnil~
or
g~ve
histories
of very
recent sojourn
in
This city, T.lOre than :my other pl11ce in the country, is
the center of travel to and froD other countries, including such cholera infected parts as India, Hongkong and Celebes. Specifically, it has to be recillled that before the R.ppearance of the first cases in l-{<:milt:!., recent outbre.:J.ks of Paracho-
ler11 El Tor were reported in certi'.in p:--.rts of Eastern :,si11. With the exception of Celebes, these areas had been as the free of the
disease for
about the S2De puriod of tir.le
Philippines.
Sn.rawak was declared infected on July 14, 1961;Hacao, on August
14 and Hongkong, ~anilL
on :,ugust 17.
The n;.lount
of triwel between could not be I
and
these areas,
especi<:11y Hongkong, underestlliated
entirely
disregarded or
as a potential Quarantine
Deans
of entry of the infection into the City.
Deasures as
were allowable under the: International Sn.nitary RegUlations were strictly enforced, but these required only present".tion of volid iUl.Junizi.'.tion the certificates and f.".cilitated the reoognition of
clinical disease. played by
Such neasures did Eut consider the poshealthy carriers and, thereforG, did not 2) If this epidemic were
sibi~_r~le
preclnde Uwir entry into the country,
neonsly in se'Iorc1.l F.ury "(oeus.
are;~s
in t;l,O
con}1tr~r
:md not from o. sin[;le 'Jri-
3) "cron1 t1~e last C."1.S0 ::mCl, r.1oc.th ro')orteci in 19)7 to
This :i.nterv,-'.l is too
,"
were reCl'rrences 01' out·T8::.ks of incli"enons oricin almost e'rery
ye,).r ')Y ye;:cr :'1.no-t>er
t~.pered
o:('f [,rD.c1l\,l.1ly to 101,1
cnc1ec~ic
levels until
e,ioer,lic hroke out.
, witJ, rer-:,rc1s to t~:e
role of c"1.rriers
D.S
sOl'1'co of in-;ection and
\-Jhi1e some authors
POS'~ll.1n-Co
t1-:>;). t cl>olerct curriers
play
0.
dnn-
[,ero\)s role in the snrN1.d of the in?ection, ot}!<'rs ror var] 011,8 rOJ.sons 1)olieve the contr,'.ry."PirCl.s (1913) in an attempt to test
73 and healthy carriers with the aid of guinea pig experiuents, found that on the average, the strains isolated frou carriers were less virulent than those from patients. And when growth initially isolated from carriers were virulent for the test aniL1als, subsequent cultures becaDe less virulent and finally avirulent." Because of this findings, Piras believes, therefore, that carriers are harmless. Similar findings were obtained by Bruce
White as mentioned in a joint report in 1948 of the Office International Hygience Publique and the World Health Organization, and by Kainford in the 1947 epidel.1ic in Egypt. Gil1aour, however, I'
-
in 1952, disagreed with these f indingG, GO that the WHO Expert Comuttee on Cholera states that "so far no conclusivE> evidence is available as to whether or not and to what extent the vibrios excreted by convalescent and contact carriers tend to be rough and to have an altered virulence" and "that further study help elucidate this point." While no further laboratory observations so far have been rede on this point during this current opideIlic, specific epide;aiologic studies and observations on the carrier state were made in various areas: :) In Bo. Lublub, Dumangas, a join~ /
iJaY
study on the Dodo of transr:.ioGicn of cholera was conducted by Major Robert E. Nitz and Major T¥cl:'.ao R. Ostrom of the Walter Reed Army Institute of Research and Dr. J. Valera of the Disease Intelligence Center. This study area was composed of enviroru~ental
35 households with 212 population. A detailed
74 study on food, water, waste disposal, housing and socio-economic condition was done. Before the study vns started, four confirmed
cases of Paracholera El Tor had occurred in the barrio from November 17 to 23rd. Rectal swabs of the entire population were
obtained and examined to determine the prevalence of El Tor vibrio in the infected population. Of the 212 rectal swabs taken, All the
seventeen (17) or $.0% were positive for El Tor vibrio.
seventeen (17) positives rcmained asymptomatic throughout the follow-up period. spite of this observed high carrier
rate, no other cases developed exccpt cne, who probably got the infection from a contaminated dug well nearby. This observation
seems to confirm the contention of some workers that the carrier plays an insignificant role as a scurce of infection or in the transmission of the disease. 2) In the Natioool Monk1 Hospi-
tal, where an explosive outhreak occurred among mentally ill patients, 100 recix'll swabs kIron from the rntients, 56 from kitchen personnel and 17 from tho dispensary personnel, Yielded
,
16 positives among tho first group, three (3) among the second and none among tho dispensary personnol. This obvious diffe-
rence in carrier rate among tho mentally ill and tho hospital personnel may be explained ~
tho differences in exposure to the
suspected vehicle of transmission w]1ich could be food served to the former and not to the latter. Subsequent rectal SWD.bs taken from the 19 positive contaets revealed the ml1.ximum duration of carrier state in this
75 purticular study to be 18 days. in one individual. days. This wns however observed only
The median duration of carrier state was 11
This wns much loncer tr.o.n the es tima ted median duration of
convalescent carrier stnte which was 4 days, the reverse of find.ings by other authors. The possibility of reinfection, however,
cannot be disregardeo. since these carriers wero isolated and confined with the cases. epidemic in MC.nila, of infection in 0. 0.
3) About two ll'.onths ::.fter the onset of the ,I
study to determine the presence or absence
population and an environment whero no clinical w~s
cases were reported in or in nearby areas,
carried out
in
some barrios of Pilar ['.TId Donsol, province of Sorsogon.
Ahout
two hundred fifty (250) reeto.l s.nbs were collected together with various seafood samples :cnd water specimens. were neeative except one rcct~l
All of the specimens fisherman which He had not been out
swnb from
0.
turned out to be positive for El Tor vibrio. of the municipality.
All the household members were negative. No
Subsequent rectal s_m.b eX..':'.minc.tions to.ken "lUre ner,n.tive.
cases hn ve occurred in those municif.C.li ties up to this time, which is four months after. This indicates that thc organism may 6~
be introduced in the population and
the environment long be4) While the epi-
foro or even without the occurrence of cases.
dernic was ragine in l-'f.o.nila and nearby provinces, an all-out effort to get rectal swab specimens of caSes and all the household contacts ~.s
mcde.
Out of tho 3,512 specimens from houseThis household contact
hold contacts, 227 or 6% were positive.
76 infection rate did not seeo to influence ~ch
the occurrence of
cases in those households since only in one or two fautilies were secondary cases observed. While the role of the carrier a s a direct source of irPfection and in the tran smission of the disease seems to be insignificant as based on the above observations, yet, in the total analysis and viewed from a broader perspective, it cannot be easily disregarded, for it, the theory of foreign origin has to be accepted, then the role of the carrier as the original
source of infection also L1Ust be recognized, since it is not 10conceivable.; that a healthY carrier with the freedom of movement that he enjoys, could easily seed any vehicle of transmission.
5.3. Vehicles of TransL1ission- In considering the spread of the disease fron one r0gion to another and locally from one area to another, there were several instances when the index case could be traced from an infected area, such as in Ilocos Sur, Masbate, Lanao Sur, and Sorsogon. 1-:cre often however, no
,
such correlation could be nude so that outbrBaks in various regions appeared unrelated. It is strongly 5ull.Jlccted that carriers
or unrecognized mild cascs rJaY have played a considerable role in inter-island or regional spread and that vehicles of transr.1ission have played a role in the local outbreaks. Throughout the prllnaF,Y outbreak in Manila and nearby areas, seafoodc were suspected all along as the main vehicle of transmission, although other vehicles and modes of transmission might
I ,
77 have played m:inor roles :in some :instances. suspicion were the followi;g: 1) About at, either raw or salted seafoods. The bases for this
y
74% of cases :investigated H
This is suspected to be the
same proportion of people eating raw or salted seafoods in the general population. ble dur:ing the time. a~~ost
Unfortunately no controlled study was possi2) Fror1 the prir,mry focus :in Manila, cases :in nearby fishing villeges and T~guig,
simultaneously occurred
coastal towns such as Navotas,
Valenzuela, and other mu-
nicipalities towards the north and south &ong the China Sea Coast while very few cases occurred along the Pacific coast and later :in inland areas. 3) The spotty distribution and sporadic
occurrence of seemingly unrelated cases, persons who never had been out of remote barrios except to farm and fish, implies or exposure to some locally available vehicles of transmission in the enviror~nt
which could have been sea foods. '
How the
_~fefoods
..:.-
could have possibly been contaminated,
can be bravely hypothesized again. The sewage of Hanila is emptied without treatment into Manila Bay near Pier 2. The presence of either a mild or un-
recognized Para cholera case or a carrier in Manila area could have contaminated tte sewage that flows out into Manila Bay and up north towards Navotas. This could contaminate in turn
fish and shellfish that might have been present in the water. At the tirne of the outbreak, the wind was then blowing in a south westerly direction
ann
this was towards the Bay, so that
78 instead of taking outne sewage into the ocean it must have concentratud, along tho banki. It :.ny be worthwhile mentioning, too, that according to,the fishemen, there was then an unusual abundance of lIal=ngll, a kind v:;:.,.,ery fine shrimps often eaten raw with calamansi juice or EnYbo pre se rved in salt, so that much of the excess in the mariets were sent to nearby provinces in Luzon. It has been sho~m
in previous studies by Cil.
r~
Nolasco
and Monsod, that cholera vibrio
n survive in IIbagoongll and even days. Countless
(salted alamang) for several hours
samples of "alama.ng" and from various area however, all failed to yeild the vibrio. Similar progressive types of outbreak as in Central Luzon were observed in most of the local outbreaks in Visayas and in Hindanao, only varying in intensity and attack rates depending presumably, upon difference in environmental condition, eating habits and level of health education in the area. yas and It; ndanao, a large portion In the Visa-
of the popUlation eat raw
fish or a,ttrimps prepared into what is locally called "kinilaw". This, together with the other factors already mentioned may have some bearinr, on the relatively high attack ·rates in those areas. In isolated instances, an explosive type of outbreak
was experienced, such as, in Calbiga, (Samar), in Lanao Sur and in the National 11 en tal H('. spital... In Lanao Sur, water was definitely established as the mode of transmission. 'Moslem areas, people utilize river In these
water for drinking, bathing, exp~,ins
and for waste disposal which readily
the explosive
79 nature of the outbreak. In Calbigp<, although w<",ter samples col-
lected did not shm-r the presence of the vibrio, epidemiological investigation seemed to point to water as the most logical vehicle. In the National Hental Hospital, food in the form of ti-
napa, a kind of smoked small fish seemed to be implicated. The above observations inciic'lte that the infection once seeded in the environment of a loc~lity,
night be transmitted The type
by various vehicles which have been contaminated.
of outbreak"fhether progressi V8 or explosive, would depend upon the extent and speed of these vf}hicles in r"aching the eonsumer hosts.
J
00
6. FURTHER EPIDEUIOLOGICAL STUDIES AND INVESTIGATIONS INDICATED. As have been indicated previously, &nd as may have been noted, the observations performed and presented may not be as complete and as adequate so as to formulate conclusions. Further epidemiological stu-
dies and investigations are therefore indicated along the following lines of approaehes: 1. Enrironmental investigation of the possible vehicles of infection especially 'Ni th reference to water and food. In any
gastro-intestinal condition, the factors of the environment aLmys play roles in the transmission. A detailed study of
.
water and food sources in an affected area is essential and must be collaborated by the required laboratory examinations. Case and outbreak investigation! must attempt to establish relationship of infection with the incriminated vehicle. 2. Continued surveillance and investigations of cases and localized outbreaks as they occur, during the waning phaae of the epidemic through the endemic level of occurrence and though a resurgence should it occur.. so as to determine the faotors ~.
'\
that maybe associated with such perSistence in a normally non-endemic area, as well as much possible forces that maybe acting to induce a resurgence.
3. Studies on the carrier of the vibrio, so as to determine the role that he play in the transmission. So far no conclusive
evidence is available aJ:l :to whether or not and to what extent the vibrio excreted by convalescent and contact earriers tend to be rough and to have an altered virulence and that
81 further investigations majr
y
help elucidate this point.
Also
more information is awaited on the prevalence and duration of the carriers state in contacts as well as in cases.
4. Field Evaluation of Cholera Vaccine - Cholera vaccine, although in extensive use for mnny years, has never been adequately evaluated in a properly controlled field trial. Studiea that have been done have been carried out by post-epidemic retrospective analysis and have depended on uninoculated persons to serve as controls. The distortions engendered
by this technique have been repeatedly documented such as to invalidate the results of this method in all but exceptional circumstances. Because of the superficial nature
..
of t he infection, the short incubation period of the disease, and, as pointed out by Macleod, the conspicuous lack of success in attempted lfe~tions ~zation
against bacterial enteric in-
generally, a real question exists ae to the value These points were all emphasized at the
I Ii
of cholera vaccine.
-
... /
Dacca Cholera Conference in 1960. A number of factors must be considered and weighed in selecting an appropriate population and the time to conduct chol~ra
vaccine studies:
1) The area must be accessible to permit large sclle immuniZation and adequate surveillance. 2) The majority of the population must be willing to accept routine immunization. 3) Persons once immunized must be subsequently identi-
82
fiable such that it may be positively established whether they had been vaccinated and, if so, Ihen and with lofhat vaccine. 4) Since the vaccine is presumed to confer, at best,
a short term protection of 6 months or less, an area should be selected where cholera may be anticipatedvithin this period. If the entire population cycle must be repeated
twice each year and large numbers are involved, the logistical problems in matching records to insure that each individual consistently receives one or another vaccine are overwhelming. 5) A population of adequate size must be given vaccine
to produce statistically valid answers.
Cal.ulation of "ade-
quate size" must be based on previoue experience ",i th the disease in the area or in presumed comparable areas. 6) On the basis of experience .Ii th Paracholera El Tor,
lower socio-economic groups are to be preferred for immunization. A more comprehensive understanding of the epidemiosalec~ve
logical pattern of the disease might indicate other
factors which could permit selection of a population in which, if
an epidemic did occur, attack rates would be disproportio-
nately high.
7) A knowledge of the past
histo~
of the population
with respect to the occurrence of cholera is desirable. Conduct of the study by use of the "double blind" technique is almost a sine qua non. By this technique, no one
83 directly '>'Orking in the appraisal has knowledge of which vaccine is which. Conscious or unconscious bias in case evaluation is, therefore, precluded. Appraisal of vaccine efficacy may be accomplished by several comparisons: 1) Relative carrier rates between differently immunized groups. 2) Relative incidence of cases of diarrhea from whom vibrio cholera is isolated. ,
--
3) Relative incidence of cases of some recognized degree of severity, e.g., those given two liters or more of intravenous fluids. 4) Relative incidence of deaths due to cholera between the two groups. Each successive approach noted yields smaller numbers for comparison and, therefore, demands the immunization of a larger population. The appronch used depends in part on whe-
ther one wishes to know if immunization reduces the acquisition of chf.1lera vibrio (particularly answered under (1) above) or whether it attenuates the disease (nos. 3 and 4 above). Both are important questions:
-I
·'
84
This is an o.tterJpt to present observo.tions and limited studies made on the diseo.se Paracholera El Tor as it occurred in the Philippines in 1961 - 1962, particularly with reference to its epidemiologiC1l1 aspects. marized as follows: 1. Cholero. used to be a seriously devastating disease
The points of presento.tion may be
sum-
in
the Philippines where major epidelaics occurred in o.n irregular but reo.sonably continuous fashion. Not a single case, however, have
been reported for the last 25 years.
Z. Eo.st~rn
Epider.dcs of P'lN.cholerel El Tor occurred in areas
in
,\sio., as Celebes, Central Asia, Saro.wak, Macao, possib!y It is believed that the in-
Southern China mId Hongkong in 1961. fection spread to the Philippines.
J.
Cases of
P~racholero.
El Tor first appeared in Manilo.
in September 22, 1961 and fron this focus, the spread continued to
,
invade successively arens in Luzon, the Visayas and Mindanao Sul~
and
So tho.t, until the 11th week of the current year
(ended
Harch 17), or during a period of 26 weeks of continuous occurrence, n total of 1~75
cases o.nd 2,064 deaths helve been so far reported
from 45 of the 56 provinces and 33 of the 39 cities comprising the country. Intensity of attack have been varied, being comparo.tiveThe
ly highest in the o.verage in the islo.nds of Hindanao ;md SUlu.
epidel:lic is definitely on its very tail end, the peo.k incidence for
..
t
85 the whole country having been reached during the middle of December (1961) with only small foci of infection in a few areas. Oc-
casional sporadic cases occur now and then in areas where the outbreaks have died out for sometine.
4.
Localized outbreaks show the range of variation in the Thus, the epi-
characteristics of the episodes in different areas.
demic in I.fanila was of the progressive type with the appearance of sporadic cases in different districts describing a spotty distribution. That in Samar was of the explosive type pointing to a common-
vehicle transmission, with a high case-fatality rate; likewise, the Laneo del Sur outbreak was explosive with transl.lission of infection by water highly suggested. On the other hand, the Ilocos Sur and
Znmboanga del Norte outbreaks were progressive and with a high incidence of multiple cases in households in the latter. At the National Mental Hospital, the initial explosive outbreak was lowed by a progressive type of extension. 5. The attack rates are definitely higher in the age groups /
fol-
above 25 years, while the mortality is highest illaong the aged, and nnong those with prinary chronic disease pathologJT. ference have been observed. No sex dif-
Most of the cases belong to the lower While some had been vac-
socio-econooic group of the population.
cinated, the percentage of these corresponds roughly to the vaccination status of the general population.
6.
Significantly higher attack rates have been observed in
• 86 coasto.l areas. Host of the cases came from poor environments
where sanitary facilities for the disposal of human wastes were l~cking.
A great majority of the cases 8ave a history of having
taken SOLle kind of sea food prior to the onset of illness and a considerable proportion p<'lrticul;,rly of thCl early cases in an area ate the sea foods raw. Extensive outbreaks were associated with 0.
an unsafe water supply, ,:!!ld a study in
limited area gave a slight
suggestion that a good w<lte r supply T.1o.y decrease the prevalence of El Tor vibrio in a population.
7. It is believed that tho disease had been introduced the Philippines, presumably by a carrier.
in-
to the country froLl any of the nearby infected ports surrounding Regional and localized
spread within the country could have been initiated PJ1d sustained by the same mechanisLl -- a carrier or 0.
case seeding the environDepending
ment and, consequently, the vehicles of transmission.
upon the extent and speed with which these vehicles, especially sea foods and water, reach the susceptible hosts, the type of epi-
,
derniC, whether explosive or progressive, is determined.
Specific
field epidemiologic studies revealed that in an infected Ll.rea, Ll.S much as
8%
of the healthy population could be carriers of the vib-
rio, with the carrier state lasting for a n:ocilJlUlTI period of 18 days and a l;)edian of 11 days.
8.
Further epidemiological studies and investigations are in-
indicated primarily on the environmental factors that Llay be
criminated as vehicles of transnission, and may be responsible for
•
the persistence and behavior of the vibrio in a given environment. Studies on th~ c~rrier
state are also necessary to answer
many of
questions on the source of infection, as well as on the mode transmission. The expected occurrence of c~ses
would also pro-
vide an opportunity for evaluating tho effectiveness of the cholera vaccine through field studies.
-88 ACKNOWLEDGEMENTS ---------------Grate:f'ul acknowledgements are due the field health personnel fran the Regional Health Directors, the Provincial, City and Municipa.l Health Officers, and down the line, for their prompt reporting of incidence, for their provision of epidemiologic data. and for their assistance and support extended to the investigating units of the Disease Intelligence Center. To the Director of Research and Laboratories and the Director of Quarantine for their most expeditious processing of laboratory materials and for the technical advises and suggestions, a.cknowledgements are hereby grate:f'ully extended. To the World Health Organization Regional Office for the Western Pacific for the assistance rendered in the procurement of vaccines and for baving invited the Canma.nd1ng Officer of the United States,
Naval
Medic~
Research Unit No. II (NAMRU II) for consultation in
connection with the outbreak. To the Commanding Officer of NAMRU II and to the Chief of the Public Health Division, United States AID OperatiOns Mission in the Philippines, for the many invaluable adVices they persona.lly gave and for baving taken the initiative of inViting experts fran NAMR1 II, the University of Maryland, Jefferson Medica.l College, too CaDmunicable Disease Center and the Walter Reed Army Institute of Research who bave so unstintingly offered assistance, advice sud encouragement. To visiting colleagues from the Camm1nicable Disease Center and
the Walter Reed Army Institute of Research, tbanks and a.ppreciation are due for the assistance, adVice and encouragement so unsel1'ishly
afforded.
Above aJ.l, to tbe Honourable, the Secretary of Health and his staff, we are extremely grateful for the support, advice, encouragement and guidance so generously provided the Disease Intelligence Center, without which these studies and. investigations could not have been possible.
REFERENCES
1. 2. 3.
Pollitzer, R., CHOLERA, WHO, Geneva, 1959 Philippine Journal. ot' Science, 1906 Bureau ot' Health, Annual Reports, 1916 - 1937 NWSA, Annual Report, FY 1960 - 196J. Disease Intelligence Center, Philippines Vital and Health statistics, 1960
4. 5.
6.
DIC Epidemiological Bulletins, Vol. 1, Nos. 1 and. 2, 1962
WORLD HEALTH ORGANIZATION
ORGANISATION MONDIALE DE LA SANTf
REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
MEFJrING FOR THE EXCHANGE OF INFORMATION ON EL TOR VIBRIO PARACHOLERA
WPR/ Cholera/4 4 April 1962 ENGLISH ONLY
Manila, Phi),ippines 16.19 April 1962
AN EPIDEMIOLOGICAL AND lMMUNOLOGICAL S'lUDY OF EL TOR V:rmu:O PARACHOLERA IN NEGROS ORIENTAL1 PHILIPPINES I
This paper bas been prepared by Dr. G. W. Beran, Director of Research, Silliman University Mission Hospital, Dumaguete CitYI with the collaboration of the following: Dr. Federico N. Florendo
Director Silliman University Mission Hospital Dr. Pio Iauengco Provincial Health Officer
1
I
Dr. Ones:l.mo de Mira Dumaguete City Health Officer Dr. Pablo Barrios Director Provincial Hospital Dr. Francisco Calumpang Tanjay Health Officer
Dr. Julio Ortillo Pamplona Health Officer Dr. Jose S. Garcia Head, Paediatrics Department
Silliman University Mission Hospital Mr. Osmundo Ellvina and Mr. Samuel Gregorio Laboratory Technicians Silliman University Mission Hospital WPR/177/ 62
CONTENTS
1.
INTR.OIl1CTION ••••••••••••••••••••••••••••••••••••••••••• MATERIALS AND MErHODS
1 1 1
2.
................................ .
2.1
The study population
2.2 2 • .3
2.4 .3.
...•....•.•••.••••••••••.••• Bacteriological procedures •••••••••••••••••••••• Vaccination procedures •••••••••••••••••••••••••• ]mmunological studies •••••••••••••••••••••••••••
2 2 2 2
RESULTS
.............................................. .
4.
DISCUSSION SUMMARY
....: I
...
5·
·..............................................
............................................
6
REF'ERENCES
............................................
7 9 10 11
Table 1 Table 2 Table .3 Table 4 Table 5 Table 6 Figure 1 Figure 2 Figure .3 Figure 4 Figure 5
·.............................................. ·..............................................
...............................................
12
·.............................................. ........................•................•..... ••••••••••••••••••••••••••••••••••••••••••••••
·............................................. .
1.3
14
15 16
·............................................. ·............................................ . ·............................................ . ......•.......................................
17 18 19 20
WPR/ Cholera/4 Pagel 1. INTRODUCTION
Since the first recognition of El Tor vibrio ~f)acholera in the Philippines on 22 September 1961 by Uylangco, et. al. ,this disease has become of nation-~'lide concern to virtually every resident of this country, and certainly to every health authority and medical worker. The nation-wide surveillance effort so effectively co-ordinated by the Secretary of Health and the Disease Intelligence Center of the Bureau of Health has brought together information from allover the country and is now making possible the crawing of some ~~~clusions on the spread of the disease and its behaviour in an epidemic~ J. There is a need, however, for studies in depth in local situations, and for the rapid reporting of results of these stud:l.es to bring together information on the characteristics of this disease Wllich both is and is not cholera at the same time. I I
This report su~~arizes epidemiological and UaRunological information on ei~hty patienta carefully selected for clinical diagnosis of Choleriform Enteritis at the Ne~ros ~4iental Provincial Hospital in Dumaguete City. Included are clinical data, results of stool cultures in the laboratory and irnmunolo3ic~1 data on convalescent patients and vaccinees. Co-operating in the study ,gere the Negros Oriental Provincial Health Office, the Dtwaguete City Health Office, the Tanjay and Pamplona Rural Health Units, the Negros Oriental Provincial Hospital, and the Silliman University Mission Hospital, where the laboratory studies were performed. 2. l.fATERIALS AND METHODS
2.1
The study population
,
.
,
Only patients hospitalized at the Provincial Hospital were included in this study. Clinical diagnosis of Choleriform Enteritis was based on the following signs and symptoms:
2.1.1 2.1.2 2.1.3
Diarrhoea, copious, yellowish-brown or yellowish-green in colour or o~: characteristic rice water appearance; Vomiting in the majority of cases, usually repeatedly and effortlessly; Dehydrat:l.cn w:)derctely severe to severej ColGness of the extremities in the majority of cases, especially in those ~~derately severe to severe; Response to the intravenous administration of hydrating fluido, u~ually dra~atically.
2.1.4 2.1.5
·Pqe'2
WPB/ C!bolera./4 Bacteriological procedures
2.2
Fresh stool samples were streaked on alkaline nitrate agar plates (PH 8.2 - 8.5) and incubated for twenty-four hours at 37 0 C. tentative identification was based on chara~§~ristic colonial and cellular morphology as described by Wilson • Final identification(!1s based on the hemolysis of goat erythrocytes as described by Burrows ant5fhe reduction of nitrate following the method described by Merchant. 2.3 Vaccination procedures
Vaccines received by persons in this study included either cholera-typhoid-paratyphoid A or cholera vaccine produced by the Bureau of Research and Laborttories or commercial cholera vaccine manufactured in the United States. All vaccines contained 8000 million cholera vibrio per ml., 50% Inaba and 50% Ogawa types of Vibrio coama. 2.4 lmmunol08ical studies
Serum samples were collected between two and eight weeks following onset of 11lness, from convalescent patients, or more than three weeks from the date of the last injection in vaccines(6)Antibody levels were determined by the use of a modified Widal test in which six-hour peptone broth cul tures of vibrio were employed as the antigens. "lnaba" and "Ogawa" tYies of Vibrio COllllll4 and a strain of El Tor vibrio originating from Samar * were used thtoughout the study, and ten local strains of El Tor were used for additional comparisons. Serum-antigen mixtUres were suspended in hanging drops and agglutination was determined with the aid of a microscope. Antibody titres were expressed as the reciprocal of the final dilution of serum giving complete agglutination of the vibrio. ComPffiAYns of antibody titres were made with the aid of students "t" test ' • The range, the median and the geometric mean were used in the analysis of results. 3. RESULTS /
.
Included in this ~epo~t are data on eighty patients hospitalized at the Provincial Hospital. Although Choleriform Enteritis was reported throughout the province"seventy-six of the patients (95%) resided within forty-five kilometres of Dumaguete City. The geographical distribution of the cases is shown in figure 1.
II Drug Co •• Philadelphia, and Wyeth Laboratories, Inc., Marietta, Pennsylvania, U.S.A. **Type cultures of these organisms were graciously supplied by Dr. P.R. Aragon, Institute of Hygiene, Manila.
,I
- !!
* National
II
II
WPR/ Cholera./4 Page
3
Patients included in this study were admitted to the hospital between 29 November 1961 and 27 January 1962. Only one person.had been admitted earlier with a clinical diagnosis of Choleriform Enteritis and specUnena were not submitted from this patient for bacteriological culture. After 27 January and until 12 March 1962, only three patients were admitted to the hospital as Choleriform Enteritis cases; all were positive on laboratory culture of their stools. Fifty-six of the eighty patients (70%) had their tUne of onset during the five-week period from 10 December through 13 January. The greatest number of cases recorded on a single day was six on 16 December, and the greatest number in one week was fifteen, during the week of 24-30 December. The median day of onset for patients in this study was 18 December. The dates of onset of patients are shown in figure 2.
-'
.
Organisms characteristic of cholera vibrio were isolated from thirty-three of the eighty stool specUnens placed in culture. Fifteen randomly selected strains showed hemolytic activity against goat erythrocytes and ten randomly selected strains showed a positive Cholera red test. Patients ,1elding vibrio in their stools were classed as definite cases (see figure 2). The sex ratio of the patients was 44 males (55.0%) to 36 females (45.0%). Among the 33 definite cases, 21 were males (63.6%) and 12 were females (36.4%). Patients were recorded in all age groups, the youngest being six months old and the oldest eighty years. The percentage of the cases in pre-school children, below four years of age, approximated the percentage(9) of the population in that age group as based on the 1957 estimated census Among the children of school age, especially those ten to niaeteen years of age, the incidence was below that which would have been expected on the basis of the age distribution of the population. Conversely, among adults. 20 to 54 years of age, the incidence was proportionately higher than the population distribution for those age groups. The age distribution of the definite cases paralleled fairly closely that found for all cases in the study. These distributions are shown in figure 3 • Stool specUnens collected on several different days from each of ten definite cases yielded the El Tor vibrio as long as five days after the onset of the disease; the(i8% end point of shedding as determined by the method of Reed and Muench ) was 4.26 days. Classification of the results of cultures of stool samples collected from all patients in this study by time from onset to collection showed that eighty per cent of the specimens obtained on the day of onset yielded El Tor vibrio on culture. From the first to the fifth days after onset, between twenty-five and fifty-seven per cent of the stool samples were positive. One of five specimens on the liinth day, and a single specimen on the tenth day were also positive. Among the ten patients submitting repeated stool specimens, all of ten rice water stools and ten of twenty-three non-rice water stools (43.5%) were positive. Among all specUneOB submitted for culture, twenty-nine of thirty-seven rice water stools (78.5%) and fourteen of
.'
WPR/ Cholera/4 Page
4
fifty-nine non-rice water stools (23.4%) yielded the El TOr vibrio. Not included were four rice water and three non-rice water stools which were sterile on bacteriological culture. Data on isolations of El Tor vibrio by days after onset and stool .type are presented in table 1. A search was made for inapparent carriers among the familial contacts of twelve patients, by the collection and culture of rectal swabs while the patient was still hospitalized. Sixty-two healthy familial contacts were examined; none of these subsequently became ill with El TOr vibrio paracholera. Three inapparent carriers were detected, two in a family where the patient produced a bacteriologically sterile stool specimen and one in a family where the patient was a laboratory confirmed case. This gave a 16.7% family carrier rate and a 4.7% individual inapparent carrier rate. Data on inapparent carriers in familial contacts of patients and laboratory results on cultures from cbe patients are shown in Table 2. Forty-six of the eighty patients (57.5%) were not vaccinated with anti-cholera vaccine prior to the date of onset of the illness. Among the thirty-four persons who had received the vaccine, "-tween two and thirteen received their immunization within ten days of onset, the eleven patients being unable to give accurate information on the time of their immunization. If these thirteen persons are classified as questionable in regard to having sufficient time to develop immunity in response to vaccination, then twenty-one of the patients (26.3%) had received proper immunization. The records of the Provincial Health Office show that approximately 28.6% of the population of this province was vaccinated by 8 December 1961 or ten days before .the median date of onset of patients included in this study. Excluding the percentage of people vaccinated during this ten-day period and excluding those patients who may have been vaccinated during the ten-day period prior to onset of the disease, then the percentage of cases occurring in both the vaccinated and the unvaccinated groups approximates the percentage of the general population iG each of these groups. The proportion of the cases in each group which were laboratory confirmed was relatively constant. The vaccination record of the patients is compared graphically to that of the general population in Figure 4. Agglutinating antibody levels were determined on serum samples collected from twenty-four definite cases. Relatively high titres were found in all samples against El Tor vibriO, the geometric mean titre being 332.2. The results obtained against "Inaba" and "Ogawa" antigens when compared by the "t" test showed a probability of difference of leu than 0.05, so the geometric means of the two results were calculated and classed as Asian vibrio for comparison to El Tor vibrio. Serums from convalescent El Tor vibrio paracholera patients showed antibody levels against Asian vibrio about one-half as high as observed against El Tor vibrio, the geometric mean titre being 176.3. Eleven of the convalescent serums were obtained from persons who had received anti-cholera vaccination; thirteen were from persons who had not received vaccine. Antibody levele in those patients who had received vaccine were 18.04 higher against El Tor vibrio and 26.8% higher against Asian vibrio than in the unvaccinated patients. Median titres were quite similar to geometric mean titres.
•
,
WPB/ Cholera./4 Page 5 1be range, median and geometric mean titres are shown for all cases,
unvaccinated cases and vaccinated cases in Table 3. Antibody levels were also determined - on serum samples from fiftyfive persons who were not El Tor vibrio faracholera patients. Five of these persons had not received anti-cholera vaccine; antibodies were not detected at 1:10 final dilution of their serums against any of the three types of antigens employed. The fifty vaccinees who submitted serum samples for analysis included persons who had received from one to twenty injections of anti-cholera vaccine during the past twenty-five years. For all of these persons, at least three weeks had elapsed since the last injection and forty-three had received their last injections within the preceding six months. Antibody titres in these vaccinees were much different from those recorded in recovered El Tor vibrio paracholera cases. The titres against Asian vibrio were about equal to those observed in convalescent persons who also received vaccine, but the geometric mean titres against El Tor vibrio were only 7.0% as high in vaccinees as in those who had clinical infection. Antibody titres against both Asian and El Tor vibrio were quite consistent in all vaccines tested. There was only one person who had a titre of forty against the Asian vibrio and none below this level. Only one fer son failed to show antibodies at the 1:10 dilution against El TOr and only one person had a titre greater th~, 80. Thirty-eight of the vaccinees had received Philippine vaccine; twelve had received United States vaccine. No significant difference was f.ound in the antibody titres elicited by the two vaccines, at tbe 0.05 probability level by the "ttl teet against either Asian or El Tor antigens. Median titres were comparable to geometric mean titres in all groups. The range, median, and geometric mean titres are shown for all vaccines, and for the group vaCCinated with each of the two different vaccines employed in Table 4. Antibody levels following vaCCination, infection, and both infection and vaccination are shown graphically in Figure 5. Among the fifty vaccinees tested for antibody levels, thirty-four had received their last injections within three months, nine between three and six months, and seven more than six months before collection of the serum samples. Antibody levels were higher in those persons who were more recently vaccinated but no definite rate of decay could be ascertained. The group last vaccinated more .than six months prior to testing included four persons who had not been vaccinated during the preceding one to ten years. One person last vaccinated in 1959 had an Asian titre of 113 and an El TOr titre of 10. Two persons last vaccinated in 1958 had Asian titres of 95 and 56.5 and El Tor titres of 20 and 20, respectively. One person last vaccinated in 1951 had an Asian titre of 134.5 and an El Tor titre of 20. The antibody levels in vaccinees according to the time since the last injection are shown in Table 5. Fifteen of the thirty-four persons last vaccinated within three months of the time of testing had received a total of one to four injections of anti-cholera vaccine during their life time. The other nineteen people had received frequent injections in previous years and no exact records were available of the regularity of these ~izations among the fifteen persons first vaccinated as a protective measure against the current outbreak. The greatest antigenic response was elicited by the
,
,
,-.....
.
-~-
WPR/ Cholere./4 Page
6
initial ~njection of vaccine. Booster dos.. were variably followed by a small increase in the antibody titre. The data on the booster effect of repeated injections of anti-cholera vaccine are summarized in Table 6. 4. DISCUSSION
The clinical manifestations of El Tor vibrio paracholera, especially in patients sufficiently ill to require hospitalization, were sufficiently characteristic during the epidemic described here that clinical diagnosis was used as the criterion for tabulations of geographical and age distribution of cases, for the epidemic curve, and for the vaccination records of patients. The diagnostic criteria ~loyed in this study were similar to those described by ijflangco, et. al. Wherever the data were presented in graphic form in this report, the proportion of the clinical cases which were laboratory confirmed is also shown. This proportion ranged near one-half of the clinical cases in all methods of classification af tbe patients where the number in each group was sufficient for such comparison (see Figures 2, 3 and 4). For ~unological studies, only definite cases were selected. Further serological studies are now in progress to obtain evidence on the proportion of clinical cases which do not yield the El Tor vibrio on culture but are actually cases of El Tor Vibrio paracbolera. The geographical distribution of the cases in this study was greatly influenced by proximity to the Provincial Hospital. The higher incidence of the disease in the male population and the age distribution skewed t~)the higher age group were also shown in the report by UYlangco, et. al. and the high incide?~, of the disease in older people was noted in the report by Dizon et. al. on the epidemiology of El Tor vibrio paracholera in the Philippines. The occurrence of EI Tor vibrio paracholera in children under one year of age which receive principally milk (usually breast milk) or foods cooked until very soft, raised some question on tbe role of foods in the transmission of the disease. Factors other than the eating of raw sea foods, raw vegetables and unpeeled fruits must be considered in the spread of the disease to these infants. Among the four "P I sIt of enter ic infections, "food, fingers, flies and fomites", attention must lie paid to the last three factors as well as to food. Sanitation was found invariably to be poor in the homes of patients seen by the authors. Improved sanitation and habits of personal hygiene may have been important factors in the low incidence of the disease in school children and conversely in the high inCidence in older adults. Although the vaccination cempaigns in this province centred around the schools, the data obtained in this study ~ointed out the importance of measures other than vaccination with Asian type cholera vaccines in the ~prevention of the disease. The role of inapparent carriers in the transmission of El Tor vibrio paracholera could not be determined from the data collected in this study. The low incidence of the disease among children in schools where members of many families are brought together in relatively close contact. indicated that if inapparent carriers are common in the general population, the spread of the infection from them to other persons can be prevented.
.
'
II
WPR/ Cholera/4 Page
7
I"".
I \
El Tor vibrio paracholera patients studied in this outbreak were found to be most uniformly shedding vibrio in the stools during the early part of the clinical disease. The period of first symptoms of the illness before patients are hospitalized should be considered as dangerous. In only rare instances were the patients in this study found to harbour viable vibrio after the fifth day of the illness. The shedder state in patients usually continued beyond the disappearance of the rice-water stool and the visual appearance of the stools could not be used as a criterion of the el1mina~ion of vibrio from the intestinal tract. Studies not reported here on a limited number of patients indicated that the oral administration of broad spectrum antibiotics inhibited the recovery of vibrio from the stools within a few hours. The current policy at the Provincial Hospital is to discharge 11 Tor vibrio paracholera patients only after at least five days of hospitalization and if possible to dispense antibacterial drugs for a tbree-day treatment after discharge. In collecting stool samples for laboratory culture, it was found to be important tbat tbey be obtained as early in the clinical course of tbe disease as possible, and certainly before the administration of antibacterial therapy. The epidemiological data reported bere indicated that the pre.,nt Asian anti-cholera vaccine em 10 ed in this epidemic was relatively ineffective Aisease. The laboratory ta s '---eathat agglutinating antibody levels elicited by tbe vaccine were very low against tbe 11 Tor vibrio. The antigenicity of tbe 11 Tor vibrio waa demonstrated by tbe relatively higb titres that followed clinical infection. !he anti-cholera vaccine stimulated production of moderately bigb antibody titres against tbe Asian vibrio but the beterologous response was minimal. Following 11 Tor vibrio paracbolera infection, tbe development of antibodies against Asian vibrio was mucb greater tban tbe development of antibodies against 11 Tor vibrio following vaccination with Asian vibrio. In the relatively small study population on wbicb tbis report was baaed. the greatest antibody development followed tbe initial injection of the vaccine and little . booster effect was obtained following repeated injections. The decay of antibodies appeared to be relatively slow. and only about a Sat decline was noted during one to ten years after iaIIIunization. It is hoped tbat furtber studies on the efficacy of tbe pre'tf~ vaccine may be forthcoming. The questions raised by other workers ~ ) on tbe efficacy of the standard vaccine in tbe prevention of Asian Cholera are multiplied in terms of its aid in tbe prevention of 11 Tor vibrio paracbolera. The data presented here indicate a need for further studies on all aspects of iaIIIunization against 11 Tor vibrio paracbolera. including vibrio types to be incorporated inthe vaccine, duration of u.aunity, and effect of repeated injections. Some of tbese studies are cureently in progress in tbis laboratory. 5.
StHfARy
A relatively small outbreak of El Tor vibriO paracbolera was recorded in tbe province of Negros Oriental during tbe latter part of 1961 and the early part of 1962. ligbty patients bospitalized at tbe Provincial Hospital were studied. The greatest number of cases came from
WPB/Cbolera/4 P~e8
people in the older age groups and the smallest number were children of school age. El Tor vibrio was receovered from 41.3% of the patients. The highest incidence of shedding in the stools was during the first five days of the illness. A 4.7% inapparent carrier rate was found among familial contacts of twelve patients. The percentage of cases of the disease which occurred in vaccinated people was approximately equal to the percentage of the population of the province which received anti-cholera vaccine. Relatively high agglutinating antibody levels against El Tor vibrio were found in convalescent patients but the levels elicited in response to anticholera vaccination were found to be minimal. Little or no booster effect was noted following injection of repeated doses of vaccine.
.•
WPR/ ChOlera/4 Page 9
REFERENCES 1.
Uylangco, C., Fabie, A., Primicias, P., and Geronimo, A.: Choleriform Enteritis. Jour. P.M.A., 38, (1962): 1-10. Dizon, J.J., Henderson, D.A., Florio, L., and Joseph, P.R.: Cholera El Tor. A Report to the Secretary of Health, Feb. 1962. Wilson, A.T.: The Cholera Vibrios. Bacterial and ~cotic Infections of Man. J.B. Lippincott Co., Philadelphia, Pa. (1958): 463-469. Burrows, W.: The Cholera Vibrio and Re lated Forms. Textbook of Bacteriology. W.B. Saunders Co., Philadelphia, Pa. (1949): 478-491. Merchant, I.A.: Bacteriological Technics and Methods. Veterinary Bacteriology £nd Virology. Iowa State College Press, Ames, Ia. (1950): 100. Widal, F.: "Student": Bull. Soc. Med. Hop. de Paris, 13 (1896): 589. Biometrics, 6 (1908): 1.
2.
3.
,, -~
r--,
4.
5.
6.
7. 8.
Fisher, R.A.: Proc. Internal. Math. Cong., Toronto., (1924): 80S. Aromin, B.B.: The Demographic Situation in the Philippines. Rep., 2 (1958): 1-6. The Stat.
9.
10.
Reed, L.J. and Muench, H.: A Simple Method of Estimating Fifty Percent Endpoints. Am. J. Hyg., 27 (1938): 493-497. Henderson, D.A.: Coomunicable Disease Center, Atlanta, Ga.: Personal Communication, 1962.
11.
WPR/ Cl:¥:J1era/4 Page 10
Table 1.
Isolations of Vibrio by Days After Onset
P ti t: Date of: a en: Onset A.Z. 12-16 1-4 1-6 1-13 1-13 1-14 1-22 1-22 1-23 1-27
Days 0 1 2 3
After 5
Onset 6 7
4
8
9
10
11
CD f"+1
.
R.G. T.L. C.N. R.C. H.D. P.V. G.C. C.A.
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:(J~~)~U~O:C): 0:0: : . . O~
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m
m tIl
0:
· 0:0:· 0 · · ~~ 8~ - . O· 3/3 4/7 0/3 1/5 0/1 0/1 3/7 3/8
N.J. Total Ail Patients
8 4/5
· '0 · 0/2 0/2
8: 0/1 1/2 0/1
.
. . . :20/39:11/21: 2/8
7/7
5/5
2/3
· 1/1: 0/1
+-
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+
Vibrio isolated from stool Vibrio not isolated from stool
C==I
lndicates rice-water stool Indicates non-rice-water stool Positive/total specimens
c=J 4/5
WPR/ Cholera/4 Page 11
Table 2.
Inapparent Carriers among Familial Contacts of Patients
Patient Initials A~
F .R. : E.N. : F .N.: C.N. : R.C. : L.C.: P.M. : E.S.:
G.D.: R.D.: A.A. : M.B. : N.T.:
Patient Culture Positive Fami11a1 Contacts
+
+
+
+
+
S 2/7 0/7 0/6 0/5 0/2 0/2
,.
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0/6
0/6
0/6
1/5
0/5
O/S
.
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,......
+
Stool culture positive for El Tor vibrio Stool culture negative for E1 Tor vibrio
S At
Stool culture sterile
N.T. Stool not submitted for culture ~
2/7
Contacts positive for El Tor/Total contacts tested
WPR/ Cho1era/4 Page 12
Table 3.
Antibody Levels in Recovered Cases
Classification: ,
Range of Titres E1 Tor Asian 80-320 80-226 80-320
Median Titre E1 Tor 320 320 320 Asian 160 160 226
Geometeic Mean Titre E1 Tor 332.2 308.0 363.0 Asian 176.3 ~
t
All Cases Unvaccinated Cases Vaccinated Cases
160-1280 160-640 160-1280
153.1 205.7 A
----
WPR/ r:bo1era/4 Page 13
Table 4.
Antibody Levels in Vaccinated Persons
Range of Titres Vaccine A
Median Titre E1 Tor 20 20 20 Asian 226 226 269
Geometric Mean Titre E1 Tor 22.7 22.4 23.8 Asian 209.8 197.5 253.8
E1 Tor All Vaccines (10-113
Asian 40-640 40-640 80-452
r-. f
, ,./
Philippine Vaccine United States Vaccine
. : «: 10-113 10-80
~
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WPR/ Cholera/4 Page 14
-
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,
Table 5.
Duration of Antibody Levels in Vaccinated Persons
Time Since NUII1ber of Last Injection: Persons <3 months 3-6 months >6 months 34 9 7
Geometric Mean Titre Asian 207.0 239.6 168.0 El Tor 24.9 17.8 18.4
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WPBtcho1.era/4 Page 1.5
Table 6. Booster Effect of Repeated Injections in Vaccinated Persons
Number of Injections
Number of Persons
Geometric Mean Titre Asian 159.8 134.0 226.1 H1 Tor 28.3 .
1 .2
2 7
31.2 33.0
3-4
6
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FIGURE I GEOGR1,PHICAL DISTRIBUTION OF CASES
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.. WPR/Cho1era/4 Page 19 FIGURE IV VACCINATION RECORD OF PATIENTS CctilPARED TO GENERAL POPULATION
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.. WPR/ Cholera/4 i---pa-ge 20
-------------------1 :?IGuB.E V
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COMPfL1L>ON OF ANTIBODY LEVElS FOLLOl.vTNG Th'FECTION AND VACCDMTION
360.,
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El Tor Asian Infection but Unvaccinated
El Tor Asian Vaccinated but no Infection
El Tor Asian Vaccination and Infection
..___._______, ___________________________--.J
I
I
.
.., WORLD HEALTH ORGANIZATION ORGANISATION MONDIALE DE LA SANT'
·Co
REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
MEETING FOR THE EXCHANGE OF INFOIlMATION ON EL TOR VIBRIO PARACHOLERA Manila." Philippines 16-19 April 1962
WPR/Cho1era/5 11 April 1962
)
........
REMARKS ON THE EPIDEMIOU>GY OF THE 1961-1962 EL TOR EPIDEMIC by
1
Dr. Oscar
~senfe1d --~~ , .• _
,._ r_., .....
J . '
.. )
~ector.. United states Component, Cholera Research Laboratory, Bangkok, TbaUand.
WPR/195/ 62
.
. WPR/ Cholera! 5 Pagel
Since the studies of de Moor (1939), there was a general belief that the El Tor infection in the Celebes has no tendency to assume epidemic proportions. Due to reasons unknown to date, after the infection was exported during World War II to Java and Singapore (Dr. Ng See Yook, 19(2), and sporadic cases occurred during the late 50's in Djakarta (Professor Ghan, 19(2), during 1961 the El Tor vibrio found its way into other parts of the Pacific area. One lias to add that the disease remained non-seasonal in the Celebes where 10;1 cases with 29 deaths were observed, fairly evenly distributed throughout 1961. The first cases outside the Celebes were reported in a small camnunity near Kendal in May. According to reports (Dr. Sovrlich, 1962), it was brought along with a seafaring visitor frem the Celebes who had seme diarrhoea and who returned to his island before the epidemiologic investigations could be carried out. Travellers and food brought from the Celebes were suspected in the transmission of the disease to further localities along the northern coast of Java, namely, Semerang and Djakarta. The infection was also carried to Bandung where, however, it did not take a foothold. Borneo was infected in August and. by November 1961, East Java, SUmatra, as well as one of the smaller islands near Timor reported cholera cases. To January 1, 1962, 4107 clinically tYllical cases of cholera with 8)7 deaths (21.~) were brought to the attention of WHO. This number does not include patients from an outbreak in the Central Hospital of Djakarta which involved 92 persons in about 10 wards. These were third class patients who had their own kitchen but the vehicle of the infection could not be ascertained.
• 'll-
• ..t.
During June and July 1961, rumours were circulating about a cholera epidemic in KWantung. A news broadeast reported from Canton 234 cases with 23 deaths. The outbreak was labelled as a paracholera infection. Later, travellers reaching Hong Kong from Kwantung had vaccination certificates proving that they were inoculated against the "four diseases", namely, cholera, tYllhoid, paracholera A and B. ~
-
During the last days of June, a regatta took place in Kuching, Sarawak, in which boats from the Celebes participated. The first cholera cases appeared on July 1, 1961 in the part of Kuching called Surabaya, where the boats were anchored. The Sarawak epidemic lasted practically two weeks and involved 582 persons with 79 deaths (11i). cases. During the first days of August 1961, Macao experienced its first Thirteen patients with six deaths were diagnosed.
Nearby Hong Kong followed on August 15. Seventy-two cases with fifteen deaths (20.~) were registered. While the persons who actually imported the disease to Hong Kong and. the New Territories are unknown, it is noteworthy that the first case appeared in a small fishing camnllD jty near Kwantung and the second in a boat-dwell1ng population who are notoriously on the move between Kwantung, Hong Kong and the New Territories.
WPR/ Cholera{ 5 Page 2
In the Philippines, the first instance of cholera was diagnosed on September 22, 1961 in a poor neighbourhood of Manila. The family of this person and the second. victim bad close contacts with the Northern Port District of Manila where ships from many Asian countries call. The infection spread. mainly southwards throughout the islands of the Philippine Archipelago, sparing the Bicol peninsula and. the jurigle areas. It did not take a strong foothold in the interior of the islands, except in the regions of lakes. According to Dr. Dizon (1962), about 15 000 cases with 2005 deaths (approximately 13%) were ill up to March 1.
Cholera was introduced to British North Borneo by a person fran the Jolo Island of the ?hilippines who went to North Borneo and became ill there. At least one mor,~ case was introduced to North Borneo fran the Philippines, and. thus in March 1962 North Borneo started to experience El ~or cholere.• On that date, cases still occurred in the Philippines, mainly in the South, and in Indonesia. The epidemiologic pat.tern of this infection does not differ fran that observed in "true" cholera as described by Seal (1960), Seal et ale (1960), Abou~eeb (1960) ~ Morgs.-''l et ale (1960) and Amada (1961) during the past years. 'l:lla::J. Tor epidemic is also restricted to poor people, inhabiting bustees or slums with little or no sanitation and unsatisfactory water supply, to offshore fishermen and. boat-dwellers with less than minimal sanitary facilities and bad bygienic habits. The present epidemic is also limited to coastal areas and to the vicinity of rivers and lakes, where properly treated water is not available. Shallow wells and. canals with high saline content and organic materials are characteristic for most of the involved areas. Hilly regiOns, jungles and. coasts with steep sho'~es, rapid rivers and strong sea waves, like those of the southern coast of Java, remained free fran this infection.
!.j'
Water definitely plays the most im~~nt rQle in tBe ~~~sm1s§~Qn of the disease not only because of the possible survival of the vibrios Iii them bUt becaUSe of its repeated contamination by carriers and patients. Fish and shellfish ~~y playa secondary role in the transmission of the disease but the quantity of vibrios ingested by eating such food is usua.lly smaller than that taken in with contaminated water when drinking or Swimming in it. The number of vibrios adhering to dishes and other eating a.r.d drinking utensils washed in contaminated water is also considerably high. Nearly all affecteQ mQuicipalities were of riverine nature, often with tidal inlets and lacldng sufficient treated water, especially during the dry season. Since such conditions favour successive contamination, a ·,0/'9.ter-bo::ne outbreak does not have to be necessarily of explosive nature in these localities. It can be postulated that this was the cause of the relative absence of explosive outbreaks in the cities afflicted by the present epidemic. The infection often spread along rivers, upstream. This can be partly attributed to funeral customs in the area which attract maD1
..
......
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- '--
.'
WPR/ Cholera/ 5 Page 3 relatives and friends from upriver areas who then carry the infection back to their longhouses, kampongs or other types of' camnunities. The lack of ability of the infection to acquire a solid foothold inland may be due to the more sparce population, greater isolation of the localities and the self'~ification of the rivers, the greater dilution factor in them, and the use of wells by a more limited number of persons. Apart from the Mainland, the Chinese population of the area was little affected. This may be due to their habit of drinking tea and eating freshly cooked food, as well as to their long-standing adaptation to urban life where sanitary custcms are different from those in the barrios, longhouses and kampongs, wherefrom many of the recent nonChinese city dwellers come.
Thus the El Tor outbreak in the Pacific area did not take an unusual course for a cholera epidemic. The remedies, therefore, have to be the same a.s those applied against cholera.:
1. 2. 3.
4. 5· 6.
~--7.
8. 9.
Reporting Quarantine and isolation Amelioration of sanitary conditions----Public health education Treatment of cases and carriers Proper laboratory diagnosis Immunization with an effective vaccine Legislation International co-operation
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WPR/ Cholera/ 5 Page
4
FtEJ!'ERENCES
1. 2.
Abou-Ga.reeb, A.H. (1960): Cholera in Calcutta during the season of prevalence, 1959. J. Trop. M.& Hyg., §2.: 122 Ama.da., Ch. (196J.): study of families in an area wbere cholera
occurred in Bangkok, Thailand. Cholera Res. Lab., 65.
Final Rept. Tbailand-BEATO
3. 4.
Dizon, J.J. (1962): Epidemiologic Reports and personal cammmication Ghan, J. L. (1962): Personal. camnmi cation.
5.
Moor, C.E. de (19") : Paracholera El Tor.
WHO Bull., g:5
6. 7. 8. 9. 10.
Morgan et ale (1960): Study of patients with mild cholera in Bangkok, Tha1la.nd, Spring, 1959. Am. J. Hyg., E :250 Kg See Yook (1962) : Personal. cammmlcation.
-
Seal,
s.c. (1960): The problem of cholera in India. J. PUbl. Health, !±.:l
SUpple Indian
Seal et ale (1960): Cholera in Greater Calcutta. Health, 4:2;) Sovrlich, D. (1962): Personal camnunicatlon.
Indian J. Publ.
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WORLD HEALTH ORGANIZATION ORGANISATION MONDIALE DE LA SANT~
...... REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R£GIONAL DU PACIFIQUE OCCIDENTAL
WPR/ CbDlere./ 6 12 April 1962 ManUa, Philippines 16-19 April 1962 SQ<lE CHARACTERISTICS OF THE EL TOR VIBRIOS
ENGLISH ONLY
ISOLATED FRa.f THE 1961-1962 EPIDEMIC
by , Dr. O. Felsenf'e1d1 and 2 Dr. S. Mukerjee
II
...
ID1rector, United States Canponent, Cholera Research laboratory, Be.ngkok, Thailand.
2Indie.n Institute for Biochemistry and Experimental Medicine, Calcutta.
Wffi/199/62
WPR/ Cbolera./ 6 -"
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Page 1
1.
Im'ROOOCTION
Textbooks of bacteriology usually summarize the differences between cholera vibrios (V. comma. or V. cbolerae) and El Tor vibrios in a more or less categorfc statement tbe.t the El Tor vibrios are be.emolytic and give a positive Voges-Proskauer test, while cholera. vibrios do not. Cholera. vibrios are assumed to cause endemic and epidemic cholera. El Tor vibrios are said to occur only in mUd disease, in water during interepidemic periods, but are not supposed to cause epidemics. Abdoelracbman (1944-45) differentiated two types of El Tor vibrios. The Yam Zam type is found in tbe Near and MiddJ.e East, causillg mUd diarrhoea or no symptans at all. The Celebes type bas its bane in the Celebes and wbile causing higb mortality but low morbidity, it does not becane an agent of epidemics. Mukberji (1955), however, described an El Tor outbreak in Iuclmow and Felsenfeld et al. (1961), an El Tor epidemic in Ubol, Tha.Ue.nd. The events of 1961-1962, when El Tor vibrios spread over Indonesia, Britisb Borneo, KwantUOS, Hong Kong, Macao and. the PhUippines, proved tbe.t it was a fallacy to believe that El Tor stra.ins are unable to cause epidemics. While the isolation of El Tor vibrios does not cause undlle difficulties in the laboratory, the classification of the strains is not easy in a.ll instances. Those cultured fram cases of illness belong to the "0-1" serologic group of vibrios and react with Ogawa and/or Inaba sera.. The biocbemica.l characteristics and the specia.l tests recommended for their differentiation fram cbolera vibrios were summarized by Pollitzer (1959) and Multer jee and Gube. Roy (1961). It can be stated that none of the previously recamnended metbods of differentiation (baemolysin), Voges-Proskauer, soda agglutination, soda sublimate, cbloropb~ and beat test) proved satisfactory in a.ll instances. Mukerjee and Gube. Roy (1961) found, however, tbe.t phage typing permitted them to distinguisb cholera. and El Tor vibrios in every case.
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El Tor vibrios proved to be insensitive to phage group IV whicb un!versa.lly lyses a.ll "true" cholera vibrios.
,
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Felsenfeld (1960) reported on the difference in the toxin production of' cholera, Egyptian (z.am z.am) and Celebes El Tor stra.ins. Cross~bsorption tests and cross-protection experiments witb different culture extracts and superne.tes as well as witb sanatic antigens shoved a difference in the toxin production of the various vibrio groups and in the antibodies formed against them. In a.d4ition, it was shown that vaccines prepared fran cholera. vibrios do not confer inRmmity against El Tor toxins even if the be.emolysin does not seem to play any part in human disease. These observations were confirmed by Briones (1962) and Aragon (1962) who found that • during the recent El Tor epidemics in the Philippines persons inRmmi zed witb vaccines prepared fran choJ.era vibrios bad low agglutination titres against El Tor stra.ins but tbe.t convalescents fram El Tor disease bad high agglut1ne.tion titres against botb cholera. and El Tor vibrios.
WPR/ChoJ.era/6 Page 2 The 1961-1962 epidemic presented an opportunity to carry out further observations on El Tor vibrios. Mukerjee and Guha. Roy (1962) e:xamined the phage susceptibility of organisms isolated in Hong Kong and found that they were true El Tor vibrios, i.e ..., they were not lysed by cholera phage group IV. They were sensitive to phage group III which is a characteristic commonly seen in El Tor Vibrios of different provenience (Mukerjee, 1961). The present paper summarizes the results of the examination of selected El Tor strains fran the 1961-1962 epidemic, canpared with El Tor of different provenience and cholera vibrios.
2.
MATERIALS AND ME.'l'HODS
The following vibrios were studied: 19 strains fran Indonesia, 2 fran Sarawak, 16 fran Hong Kong, 1 fran Macao and 25 fran the Philippines, isolated during the 1961-1962 epidemic. Five El Tor strains cuJ.tured in Indonesia during the pre-epidemic period in 1959 and 19£0: 3 stra1zls fran the 19£0 Ubol outbreak; 2 fran India dated 1958; and 6 fran Tbailand isolated during the cholera epidemic in 1959. In add1tion, 15 Ogawa and 5 Inaba strains of typical cholera vibrios, received recently fran Poena, were employed.
I
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AlJ. strains were tested for their ability to grow on B;ynes t modification of the desoxychol.ate-citrate agar, on Difco desoxycholatecitrate medium, on the bismuth plate of AhuJa et ala (1951), on the tellurite plate of Fe1senfeld and Watanabe (1958) and in Kligler's medium. Reactions in dextrose, sucrose, mannitol, mannose, arabinose and indole formation were examined. The Voges-Proskauer test was performed in the modification of Barrit and the ba.emolysin determination by the Pollitzer and Greig (Pollitzer, 1959) method. Phage typing was done according to the method of Mukerjee (1961). AlJ. vibrios were tested for lethal toxin and baemolysin formation by the procedure of Watanabe and Felsenfeld (19 61) •
For "toxin n production in :IlIImunologic tests, two El Tor strains each fran the Philippines and Indonesia, one each from Hong Kong and Sarawak, isolated in 1961, were used. For comparison, one El Tor strain each fran India, Ubol, the TbaUand cbolera outbreak and fran the preepidemic period in Indonesia, as well as one each of typical Ogawa and lnaba strains were used. The antigens fran tbase strains were prepared in duplicate, by the methods of Watanabe and Fe1senfe1d (1961) and the SN extract procedure of Ghosh and Mukerjee (1961). Tbe agar gel diffusion tests were carried out as described by Morgan et ala (19£0).
Sera were available at the United States Army-S~ Medical Research Laboratory collected fran patients, contacts, carriers and controls during the cholera epidemic in Thailand in 19 'f) -19 £0 and from the Ubo1 El Tor outbreak. Additional convalescent sera and blOod samples fran not infected persons were received fran the Philippines
, WPR/ rJbolera/ 6 Page
3
and fran Hong Kong. Only such convalescent sera were used which were collected between ten days to three weeks after the onset of the disease. Blood fran :immunized persons was taken one week to three months after the second vaccine dose was given.
Twenty-seven water samples were collected in the Philippines, in Indonesia, Sarawak and Hong Kong.
3.
RESULTS
:
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All examined cholera and El Tor strains grew well on tellurite The growth of El Tor strains was saoewhat restricted on Ahuja's plate. Cholera vibrios grew slowly on Difco desoxycholateooeitrate agar, while El Tor organisms formed larger colonies during a shorter period of time on this medium. and on ltYnes' medium.
All vibrios studied during this project fermented dextrose, mannitol, mannose and sucrose but not arabinose. The 1Dclole reaction was strongly positive. Sane hydrogen sulphide jlt"oduction was observed. in th1rty-nine El Tor vibrios fran the 1961-1962 outbreak in lO.1gler's medium. Ii
The Voges-Proskauer reaction was negative with cholera Vibrios
and with eight ElTor strains fran the 1961-1962 epidemic and two El Tor cultures fran Thailand. Among the El Tor vibrios, two Inaba strains came fran the Philippines and one fran Indonesia. One Hikojima steain was present among those fran Indonesia. All other El Tor strains belonged to the Ogawa serotype.
...
One El Tor vibrio from Thailand was non-haemolytic. Four strains from Bong Kong, one from the Philippines and two fran Indonesia failed to produce measurable amounts of haemolysin during early transpla.nta.tions. All other El Tor strains were haemolytic. Their ba.emolysin titres were between 1:80 and 1:360, or expressed in Watanabe units, 140 ~ 13.5 units for the El Tor strains from the present epidemic and for those collected in the pre-epidem1c period in Indonesia. The control El Tor vibrios fran India, Thailand and the Ub01 outbreak formed 12) + 15.' baemo.lytic units. -
Regardless to serotype, none of the El Tor vibrios was susceptible to MIlker jee' s phage group IV while a.ll cholera vibrios were lysed by this phage. The vibrios were susceptible to phage group III in working dilutions. The average lethal. tOXin production of the El Tor vibrios fran the 1961-1962 epidemic and fran Indonesia collected in 1959 and 1960 was 62+ 5.8 units; that of the El Tor vibrios from India, Thailand and the Ubo1. outbreak was 2l.!. 4.5 units as measured by the Watanabe method.
, WPR/ Cholera/6 Page 4 A.l1 cholera and El Tor vibrios produced an alpha-band when tested against human and rabbit immune sera by the agar gel diffusion method. This band represents the heat-stable cell-wall antigen of Misra and Shrivastava (1961). El Tor antitoxic sera gave one additional heat-stable band. The nature of this band will be studied further. The SN bands followed the :pattern observed previously (Ghosh and Mukerjee, 1961) •
Table I represents the most important :part of the results testing human sera with the method of Morgan et a.l. (1960). Convalescent sera fran the 196:1.-1962 El Tor epidemic showed antibody titres against all toxic filtrates which were employed. Fewer sera of convalescents after cholera infection showed significant antibody titres against El Tor toxin. Persons who experienced El Tor infections during the Ubo1 outbreak, which was caused by a less toxigenic vibriO, showed nevertheless protective antibodies against highly toxic filtrates. Vaccinated 1ndividuals presented such a.ntibodies only in relatively few instances. None of the twenty-seven vater samples yielded bacteriophages active against El Tor vibrios. 4. CONCWSIONS
!
The 1961-1962 El Tor epidemic was caused by a vibrio which belonged to the Ogawa serologic type. Most strains were haemolytic and Voges-Proskauer positive; many formed same hydrogen sulphide. Biochemically the cultures belonged to Heiberg group I. The most important and constant feature of all vibrios studied in this outbreak was their characteristic behaviour in phage typing.
These E1 Tor vibrios produced more lethal toxin than those isolated in'previous years outside Indonesia. The baemolysin production did not show significant differences. El Tor antitoxin was present in the majority of the convalescent sera but not in immunized individuals.
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., WPB/ CbtJlera/ 6 Page
5
Tablel
Sera fran
No. of sera tested
.
~
r.
Convalescents, Cholera in Thailand
.
196
.
Serum antitoxin level 1.0 or more units with extracts fran :Ogawa vibrio:El. Tor vibrio: El. Tor vibrio fran fran the fran Philippines Poona Ubol 186 138
94
Convalescents, El Tor outbreak in UboJ. Convalescents, 19 6J. -19 62 El. Tor e12idemic Vaccinated with sta.ndard cholera vaccine 41
30
32
25
36
38
106
20
17
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WPR/ Cholera/ 6 Page
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REFERENCES 1. Abdoelracbman, R. (1944-45): Vibrio reservoir in the Hejaz in connection with the E1 Tor problem. Antonie v. leeuwenhoek, !Q:93 Ahuja et al. (1951): laboratory diagnosis of cholera. Med. Res., ~:135 Indian J.
2. 3. 4. 5. 6.
Aragon, P. (1962): El Tor type vibrio in the recent outbreak of cholera. In print. Briones, T.N. (1962): The El Tor vibrio and the Manila outbreak. In print. Felsenfeld, O. (1960): Pathogenicity of El Tor and NAG vibrios. Proc. Haffkine Inat. Diamond Jubilee, 37 Felsenfe1d et al. (1961): El Tor vibrios of the Ogawa subtype in an epidemic of diarrhoea with vomiting in Ubo1, Thailand. J. Trop. M. & Hyg., .§.:207 Felsenfeld, O. and Watanabe, Y. (1958): Alkaline te11urite lauryl sulphate salt plate for the isolation of V. ccmna.. US Armed Forces M.J., 2,.:975 Gbosh,S.N. and Mukerjee,S. (1961): studies on antigens of V. cho1erae by agar gel diffusion tecbnique. II. Further observations on the antigenic analysis of materials soluble in water. Ann. Biochem. & Expt1. M., Sh:15l Misra, S.B. and Sbrivastava, D.L. (1961): Studies in iJD:nunocbemistry of V. cholerae. Indian J. Med. Res., ~:183 Morgan et al. (1960): Study of patients with mild cholera in Bangkok, Thailand, Spring, 1959. Am. J. Hyg., E:250 Mukerjee, S. (1961): Diagnostic J. Hyg., 22. :10) use of cholera bacteriophages.
7.
8.
9. 10. 11.
12.
...
Mukerjee, S. and Guha. Roy, U.K. (1961): Evaluation of tests for differentiating V. cholerae and El Tor vibrios. Ann. Biocbem. & Exptl. M., 21 :l~
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Mukerjee, S. and Guhe .. Roy, U.K. (1962): The vibrios of the recent cho1era...J..ike outbreak in Hong Kong. Brit. M.J., 1,:685 14. 15. 16. Mukherji, A. (1955): Haemolytic vibrios in cholera epidemic at Iucknow in 1945. Indian J. M. Sci., 2,.:540 Po11itzer, R. (1959): Cholera. WHO Monograph Series No. 43 Watanabe, Y. and Felsenfe1d, O. (1961): Production of V. El Tor toxin in a liquid medium. J.Bact., 82:43
J.-.
J. WORLD HEALTH ORGAN I ZATION
RETURN TO WHO LIBRARY if..Q.
GIl) &1, . ",<
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• MANJLAl P.I. ORGANISATION MONDIALE DE LA SANT' .
REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
MEETING FOR THE EXCHlmGE OF INFORMi'.TION ON EL TOR VIBRIO PARACHOLERA Manila, Philippines 16-19 April 1962
WPR/Cholera/B 16 April 1962
( ENGLISH
THE TREATMENT OF CHOLERA* by \.
Dr. Craig K. Wallace Lieutenant Commander l'ledical Corps, United States Naval Reserve Departnent of Clinical Investigation, NAMRU-2 Dr. John W. Cox Lieutenant Commander Medical Corps, United States Navy Chief of Kedicine, Station Hospital United States Naval Base Subic Bay, Philippines Dr. Anastacia Fabie Senior Resident San Lazaro Hospital Manila, Philippines Dr. Paquita Prild.c1as Resident in ~Iedicine San Lazaro Hospital Manila, Philippines Dr. Robert A. Phillips Captain· Medical Corps, United states Navy Commanding Officer, NAMRU-2 Dr. Cesar V. Uylangco Chief of Hospital IV San Lazaro Hospital Manila, PhilippiI:\es *From the San Lazaro Hospital, ~janila, Philippines, and the United States Naval Medical Research Unit No.2 (NAMRU-2), Taipei, Taiwan. This study was supported in part by funding under Public Law 480, Section 104(0). The opinions and assertions contained herein are those of the authors and are not to be construed as official or reflecting the views of the Navy Department or the Naval Service at large •
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vJPR,lCholera/8 page 1 El Tor type of cholera has been a severe problem in Southeast Asia during the past eight months. In view of this, we present here the current treatment of cholera based upon our recent experiences in the Philippines. The mortality rate at ~anila 's San Lazaro Hospital was reduced from 14 per cent to 3.4 per cent after the introduction of the treat.eDt regimen descri bed in this paper. These figures substantiate our opinion that death in cholera can be prevented by rapid and adequate correction of the severe deqydration and acidosis seen in these patients.
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The present therapy of cholera is based on physiologic studies and subsequent u:eerstanding of the disease process. It was definitely determined during the Egyptian epidemic of 1947 that there were very large losses of water, bicarbonate, sodium, chloride and potassium ions in the stool. It was further shown that analyses for nitrogen in Seitz filtered stools revealed an average protein loss of less than 0.1 gm per 100 ml of stool. This ~ l concentration of protein is far less than that observed in transudates' • The fluid loss and the fluid volume required for replacerrent in cholera were accurately estimated from the specific gravity determinations of plasma proteins by the copper sulfate method devised by Phillips, et al 5• Subsequently, the Bangkok epidemic of 1958 provided the opportunity to perform quantitative water and electrolyte studies. Important advances at that time by Watten, et al 6 l'evealec1 that fecal sodium and chloride concentrations were consist(r.tly lower than thai ~ plasma val ues, while the fecal potassium and HC03 were in greater conc61.tration than the plasma values with the potassium being 2 to 6 times and the HC03 nearly double the plasma levels. The Bangkok studies clearly demonstrated that one is dealing with essentially an isotonic dehydration~ Replacement with isotonic saline and an adequate amount of potassium and HC03 ions corrected the fluid-electrolyte deficit and subsequently maintained a satisfactory state of qydration7 •. METHOD
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Fully equipped treatment centres must be available and should be so spaced that the population can reach them wi thin three to six hours. The facility in Nanila's San Lazaro HtoJepi tal was a converted respiratory disease pavilion that provided adequate space for beds and a small area 22 September 1961 through 12 October 1961 there were 143 admissions with 20 deaths (14 per cent). From 13 October 1961 through 1 March 1962 there were 526 admissions with 18 deaths (3.4 per cent). 1,2*Gangarosa, et al.3 subsequently found that the epithelium in hUI,an intestinal biopsy specimens ren ained intact throughout the course of the disease. Gordon's work with I -131 tagged polyvinylpyrrolidone (PVP) infusions revealed no greater PvP content in the stool of the cholera patient per unit time than in the stool of normal individuals4. This was indeed conclusive evidence against the theory of massive desquamation of epithelium with tremendous outpouring of a transudate. The precise mechanism of fluid loss in cholera remains to be delineated.
*From
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v.l?R/Cholera/8 page 2 for simple laboratory determinations. It was found that all personnel functioned best with maximum efficiency and continuity by working together in eight-hour shifts. A history of copious, watery diarrhea is deemed sufficient, especially during an epidemic, to admit patients to such a ward.
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Patients should be weighed immediately on admission. Frequently, patients are unable to stand or sit unsupported because of extreme dehydration and shock. The problem can be circumvented by having the orderly hold the patient, weighing both individuals and then simply subtracting the orderly1s weight. The patient is next placed on a Watten "cholera bed" which is an army cot with a reinforced hole in the centre some eight or ten inches in diameter over which the buttocks can be placed (Figure 1). A two- or threegallon bucket* is placed under the hole and serves as an effective means for collecting all excreta wi thout the necessi ty of moving the patient and of frequent emptying and measuring of bedpans and urinals. Wooden sticks can be appropriately marked for each 500 ml so that simple but satisfactory measurements of the ~unt of excreta can be determined at any time by merely dipping the stick into the bucket. Upon placing the patient in bed, a venipuncture is performed using a number of eighte~n or larger gauge needle which is left in place, thus providing a large bore for the rapid administration ot fluids. A superficial arm vein is preferable~ A leg vein is less desirable because of the higher incidence of thrombophlebitis and embOlic phenomenon in the lower extremities. Frequently, there is little choice and in our experience we have seen no ill effects from using leg veins. In cases of severe dehydration and/or shock, we often utilized a femoral vein:, a technique which allows specimens to be obtained with ease. By holding the needle in place fluid may be given untU a "cut-downtl or some suitable superficial vein can be utilized. The blood specimen is then placed into a tube** containing an anticoagulant. An infusion of isotonic saline is started irrmediately through the large gauge needle. Since the fiuid losses generally are severe, the infusion rate should be given as rapidly as possible and may be 100 ml per minute. Rapid replacement is life saving and can be given wi th impunity to elderly
*At San Lailaro Hospital used lard cans were readily available and suitable. **The tube should contain 0.05 ml of either 0.4 per cent heparin solution or a 2 per cent solution of an oxalate mixture (12 gm of ammonium oxalate and 8 gin of potassium oxalate to 1 liter) for each ml of blood the tube is to receiveS. We believe a 3 m1 blood specimen is sufficient and therefore reoommend 0.15 ml of either anticoagulant. This is added to preferably a plaatic tube marked at the 3 m1 level and allowed to dry to a thin film.
WPR/Cho~era/8
page 3
•
patients with cardiac involvement or to children since the patients are to be rehydrated to their usual physiologic state. During the Bangkok epidemic, Watten and Philli ps 9 had no difficulties with oVerhydration. This was also our experience in Fanila. The specific gravity of the whole blood is determined by the copper sul.fate method .:hich is discussed in the appendix. After determining the whole blood specific gravity, the remainder of the blood is centrif~ed to obtain plasma for its specific gravity determination. A hand ~entr~fug? c~ be utilized, but a small electrical table model is more conven~ent. Phill~ps, et al 5 have shown that the plasma protein concentration as determined by the copper sulfate method is the most reliable guide to the extent of dehydration. Complete history and physical examinations are time-consuming and frequently misleading. Temperature, pulse and blood pressure determinations, as well as the s tate of skin turgor and mucous membranee, do not give a reliable indication of the patient's state of hydration. l"lany cholera victims are anemic and any determination of hemoconcentration may also be misleading, therefore, we do not rely upon whole blood specific gravities initially for a true indication of the patient's dehydration. Both Whole bleod and plasma specific gravities are determined so that subsequently the two values may be correlated. Once the patient is rehydrated to a normal plasma specific gravity of 1.025, one may equate the whole blood specific gravity for this individual at the same time and consider this value his "normal" whole blood specific gravity at physiologic hydration. Laboratory studies for determining electrolytes, blood counts and urinalyses are not necessary as the results will reflect the dehydration but will not provide adequate information for hour-to-hour management. The amount of fluid replacement is determined on the basis of weight and plasma specific gravit y7 (Table I). This is a rule-or-thumb means for determining the amount of isotonic fluid required to rehydrate the patient. For example, a 50 Kg adult, who is admitted with a plasma specific gravity of 1.032 would need 200 ml of isotonic fluid for each 0.001 elevation of specific gravity vbove 1.025, this would be 7 x 200 ml or 1400 ml of fluid. A child weighing 20 Kg with a similar admission specific gray! ty of 1.0)2 would reqUire 7 x 130 ml 02' 5Eo m1 (Table I).
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A simple, effective and most important aspect of therapy is the constant recording of fluid intake and output. A sheet of paper is attached to the cot, wall or I-V stand and the time and amount of all infusions are rec~rded as they are ini tiated (Figure 1). The amount of diarrhea is estlmated by using a dip stick and recording the time and amount on the ~am? sheet. U::ine and Vomitus are also recorded. I t is important to ~ndicate the t:une the excreta is emptied so that an accurate balance may be determined readily. After the calculated fluid requirement for initial rehydration is completed ~h~ infus~on rate is slowed to about .3 ml per minute. The whole bloo~ spec~flC gr~vlty value that will equate with a plasma specific gravl~y of 1.025.1S then determined thus correcting any discrepancy relat~ng ~o anemla or hemoconcentration and obviating the necessity of centrifug~ng blood for further plasma specific gravity determinations.
wpR/cho1era/8 page 4
Once the patient is initially hydrated his fluid state can be controlled completely... :'he, amount of intake may be equated to the amount of output. Watts? and Phillips 9 state that paralytic ileus from hypokalemia will occasl.onally cause sequestrat~.on of a large volume of diarrheal fluid in the bowel and may result in a misleading estimation of fluid loss. Furthermore insensible water loss must be considered. Blackwell10 has shown in studyin~ cholera patients in Bangkok that thel'S was an average 108s of 1.0 ml of water per Kg per hoUl' when the ambient temperature was JloC. Therefore in a 50 Kg man, a 24-hour insensible water loss would be 1,2~ ml (50 K~ x 24, hrs); and, in a 20 K~ child, the loss would be 480 ml (2J Kg x 24 hrs). This amount must be replaced and is added to the fluids administered. OUr experience has shown th3t determinations of specific gravity every J to 6 hoUl's after initial rehydration are a sufficient check to prevent any severe replacement discrepancy... As the diarrhea subsides the freq~ency of specific gravity determinations may be lessened. The type of fluid that the cholera patient should receive has engendered much controversyll.4 Since the diarrheal loss is prin,arily an isotonic one, the ghysiologic replacement is primarily isotonic saline. Watten and co-workers reported that an average of 45 mEq of bicarbonate pel' liter was found in the cholera stool. This loss suggests the possibility of rather severe acidosis. They stated that for each mEq decrease of plasma C02 belmT 25 mEq,lL, 0.6 rnEq/Kg of body weight of sodium bicarbonate was required to elevate the C02 to 25 mEq/L. These workers gave bicarbonate as soon as rehydration was completed. We found that 1000 ml of 2 per cent sodiu..'ll bicarbonate for each 3000 ml of isotonic saline infusion would correct the acidosis. No useful purpose is served in waiting for rehydration or attempting CO 2 determinations prior to giving 2 per cent SodiUlll bicarbonate. We have observed that vomiting and nausea are practically non-existent once acidosis is being corrected. Oral fluids may then be given. Watten and Philli ps 9 have discussed the necessity of potassium in the treatment of cholera to pre'lent :leuror.msc~u2.'l' disturbances su-::h as pa:~'llytic ileus as well as renal tubular damage end myocardial depression. They found that the addition of 10 mEq (0.75 gm) of KCl to each liter of fluid will replace at least half of the loss. As long as diarrhea persiSts there is no danger of hype:okalemia since the fecal lnsses cre approximately ~.O to 15 mE<¥'L. tJter adequate hydration and cessation of diarrhea, any evidence of renal failure would necessitate discontinuing the use of potassium supplements. We were unable to obtain p&renteral KGl during oul' recent experiences and present belo" a pOSSible, though less effective, remedial replacement of this ion. The efficacy of oral nuids in the therapeutic regimen i~ an aspect that remains to be eVClluated. However, it has been our, experl.ence ,that oral supplements, once tolerated, will afford psychologlc and ~OSSl.blY therapeutic benefits. Warmed meat broth with supplements of bl.carbonate and potassium oi trate was well tolerated by our patients. A 5. per cent oolution of sodium bicarbonate is palatable and can be added dl.rectly to the broth. Ten ml of a mixture of 100 gm each of potassium citrate, . potassium acetate and potassium bicarbonate per liter of H20,may be gl.ven three times a day ~ recommended by Watten and ph:Llllpn9 ; this too may be added to the meat broth. Tea and rice gruel were gl:'adually added to the fluid regiInen until the patient was eating a soft diet.
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,
,1 .
W"PR/Cholera/8 page 5/6 The duration of intravenous therapy was determined on the basis of three factors: 1) the termination of diarrhea, 2) the satisfactory ingestion of both fluids and a soft diet and 3) the abili ty to excrete a normal amount of urine, i.e. 1 ml per Kg of body weight per hour. These are reliable indices that the patient is able to maintain a physiologic fluid electrolyte balance without any apparent gross disturbance of the gastrointestinal system or kidneys. At this time it is convenient to transfer the patient to a convalescent ward where he may ambulate, improve his nutritional status and generally recuperate away from the tempo of the acute ward*. Considerable material has been wri tten about the Efficacy of various regimens of cholera therapy. Our therapeutic regimen is based upon the prirrary defect in cholera which is the loss of water and electrolytes and other therapeutic adjuvants are mentioned only to be condemned. We freqently found individuals treated with various vasopressor agents and cardiac stimulants. This is deemed harmful from several viewpoints. First, this therapy is not directed to the true cause of shock which is the need for fluid replacement; second, the effect of these drugs might well cause further ischemic damage of kidneys, brain and liver, leading to irreversible changes in a patient who is already experiencing maxLmal physiologic response to his dehydration. We have encountered many advocates of colloid plasma-volume expanders and other types of fluid replacement. Glucose is given frequently. Obviously this is undesirable since large quantities of glucose obligate the lddneys to eliminate sugar. The anuria, a physiologic mechanism which has responded to the patient IS need, is reversed so that even additional water' and essential electrolytes are eliminated. We do not recommend the use of sulfonamides or antibiotics altheugh many of these drugs ar,e bacteriocidal for the vibrio. There is no evidence that their use affects, the pathogenesis or prognosis of the disease.
,
\
.,'" *At the San Lazaro Hospital daily rectal swabs were obtained from patients for culture of vibrio. A convalescent patient was discharged only after three consecutive negative cultures.
WPR/Cholera/8 APPENDIX page?
J
The copper sulfate method is mentioned above as the recommended means for measuring specific grav1ties 5 • The technique consists of letting drops of plasma or whole blood fall into graded solutions of copper sulfate with known spec~fic gravitie~. The drops become encased with a capper proteinate upon.enter1ng the solut10n and remain as discreet droplets without change of graVl. ~y for some 20 seconds. During this time the gravi ty of the droplet relat1ve to the solution can be determined b,y its rise or fall. Neither the size of the drop nor the temperature of the solution* needs to be constant. The copper sulfate solution automatically cleans itself after each test and the drop settles to the bottom as a pl'ecipi tate. The standard solution decreases in specific gravity some 0.0005 units with the addition of each 50 drops of plasma or Whole blood. It is recommended that the stock solution be replaced after 50 determinations; however, in emergency situations, determinations may be continued by correcting for the changed specific gravity. We definitely recommend changing the stock solutions at about every 100 determinations. In the Philippine Islands, a series of 20 bottles of copper sulfate solutions graded at intervals of 0.00) with a range of from 1.018 to 1.CJ75 was adequate to cover the entire range of plasma md Whole blood determin~ions •. The whole blood specific gravity may be determined at the bedside by dropping the specimen directly from the syringe needle. This is satisfactory if anticoagulants are not available. The remainder of the specimen is then allowed to, coagulate and a serum specific gravity can be determined in lieu of plasma. We prefer to use anticoagulants since the plasma sample can be quickly obtained without having to wait for blood clot retraction. The specimen must be mixed thoroughly prior to the determination of the whole blood specific gravity. The specimen is optimally delivered from a height of about 1 em above the copper sulfate solution using a medicine dropper with a fine tip. It is convenient to steady the dropper on the edge of the bottle. If the drop is lighter than the test solution, after the momentum of the fall is lost i t will rise in about five ssoonds and then settle; if heavier it will continue to fall; if of the same gravity as the test solution the drop will become stationary for 10 to 15 seconds and then fall (Figure 2). A standard stock solution of copper sulfate with a specific gravity of 1.1000 is prepared by taking 159.6) gm of analytical (reagent) grade CuS04.5H20 and placing it in a 1000 ml volumetric flask containing about 800 ml of water. The contents are mixed thoroughly until they are in solution (they may have to be warmed slightly for complete mixing and then cooled to room temperature) and diluted exactly to one liter with distilled water of the same temperature. *The co-efficacy of the expansion of the copper sulfate solution approximates that of blood and plasma.
,
\
WPR/Cholera/8 Appendix
page 8 Plasma and whole blood in copper sulfate solution are somewhat lighter than the indicated gravities, therefore, one ml less than the labeled gravity of the solution is added. For example, to prepare a solution of 1.018 gravity, 17 ml of stock solution is diluted to 100 ml; 20 ml of stock solution is diluted to 100 ml and labeled 1.021, etc. The required volumes of copper sulfate solution are most conveniently delivered into a 100 ml volumetric flask from a 100 ml burette with distilled water of the same temperature added as the flask is swirled to make 100 ml of solution. After mixing, the solution is poured into an appropriately labeled four-ounce bottle. The flask is thoroughly washed and rinsed with distilled water and is then ready for the Bext preparation.
.-
-
i11PR/Cholera/8 Appendix page 9 Table I Relationship of Fluid Requirements to Weight Amount of fluid needed to rehydrate for each 0.001 elevation above a plasma specific gravity of 1.025 and whole blood specific gravity of 1.060* Weight
F, \ .t
80 75 70 65 60
320 ml. 300 ml 280 ml 260 ml 240 ml 220 ml 200 ml
240 ml. 225 ml 210 ml 195 ml 180 ml 165 ml 150 ml 135 ml 120 ml 105 ml 90 ml 75 ml 60ml
55 50 45 40 ..: /""\
180 ml 160 ml 140 ml 120 ml 100 ml 80 ml 60 ml 40 ml 20 ml
35 ,30 25 20 15 10
,
45 ml 30 ml 15 ml
\>
~
5
*whole blood epecific gravity of 1.060 is considered normal for an individual without an em a or hemoc oncentrati on. Correction for anem a or hemoconcentration is made by determining both the whole blood and plasma specific gravities taken at the same time. When the plasma value is 1.025, the corresponding whole blood specific gravity is considered "normal" and may be used for subsequent fluid calculati ons.
WPR/Cholera/8 Appendix page loIn Table II Summary - Treatment of Cholera Patients 1. 2. Weigh patient. Place on chQlera cot. Draw) ml of blood with 18 gauge needle, leave needle in place. ml per minute.
).
4. 1ni tiate isotonic saline infusion at 100 5. Record all intake and output at bedside.
-" , ,
6.
Determine whole
bl~od
and plasma specific gran ties. Give rapdilyo
7. 8.
Calculate amount of fluid needed on basis of Table I.
Upon rehydration re-evaluate specific gravities determining "normal whole blood II specific gravity and allow slow infusion to run. for insensible water loss.
9. Give fluids to balance the output using dip stick at bedside. Calculate 10. Check state of hydration with specific gravity of whole blood every ) to 6 hours during acute phase. Number of determinations is decreased as patient's condition improves. Give 1000 ml of 2 pEn' cent sodium bicarbonate for every )000 ml of isotonic salina-. Present oral fluids with potassium and bicarbonate supplements upon demand and toleration. Continue infusion therapy until cessation of diarrhea. Further adjuvants are not indicated.
11. 12. 13. 14.
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.
Qui put rec. oydC?d.
ii
,I
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II II
CHOLERA COT is an ordinary iolding canvoc;,. COT wi1h 4 g/I remfo'Yced hole li"\cldC? just abovG middlG (NOT
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directly
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is
l.lnder oPGnin~ tocollec1 siool
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WPR/Cllolera/8 Appendix page 14/15
\
\., 4-'
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(-,,-
--.....
....... 'I
'\::::--------'
1.024 Figure 2 \
1.027
This illustrates the determination of the specific gravity as would be seen with a plasma specimen of 1.025. Since the drop is heavier than the first test solution it continues to fall. In the second test solution it is lighter, therefore, after the momentum of the fall is lost it is seen to rise.
-
".
. /3
'W"PR/ Cho1era/8
Appendix page 16 References 1. Weaver, R.H., Johnson, M .. K., and Phillips, R.A.: B1.ochemical Studies of Cholera. J. Egypt. Pub. Health Association, 23, 1:5, 1948. R.~, and Phillips, R.A.: Treatrrent of Cholera. J. Egypt. Publ Health Association, 23, 1 1 15, 1948.
2. Johnson, M.K., Weaver,
3. Gangarosa, E.J., Beisel,
w..R., Benyajati, C., Sprinz, H., and Piyarath, P.: The nature of the gastrointestinal lesions in Asiatic Cholera and its relation to pathogenesis~ A biopsy study.. Amer. J. Trop.. Hed. and Hyg., 9:125, 1960.
4. Summary of SEATO Conference on Cholera. Public Health Reports, ?6 1 323, 1961.
5. Phillips, R.A., Van Slyke, D.D., Hamilton, P.B., Dale V.P., Emerson, K. Jr., and ArChibald, R.M.: Measurement of specific gravi ties of whole blood and plasma by standared copper sulfate solutions. J. Biol. Chem., 183, 1:305, 1950. 6.. Watten, R.H., Morgan, F.M., Songkhla, Y. na, Vanikiati, B., and Phillips, R.A.: Water and electrolyte studies in cholera. J. Clin. Invest., 38, lltl8?9, 1959. 7. Morgan, FeM.. , Watten, R.M., B1.dyabhed, L.B., Vejaeakdhi, L.P., Bangxang, E.M., aM .Phillips, R.A.: Treatment of Cholera. J. Med. Association of Thai-land, 42, 5=413, 1959. 8. Heller, V.G., and Paul, H.:; Changes in cell volume produced by varying concentrations ot different anticoagulants. J. Lab. & Clin. Med., 19t???, 19)4. 9. 10. li.
,-,
Watten R.H., and Phillips, R.A.: Potassium in the treatment of cholera. Lancet, 1i:999, 1960. Blackwell, R.Q.: Personal communication. I
r
Pollitzer, R.I Cholera studies. 9. Symptomatology, Diagnosis, PrognOSis and treatment. Bull. of' WHO, 16, 2t296, 1957.
;-'
--
,•
• WORLD HEALTH ORGANIZATION
A.uc ORGANISATION MONDIALE DE LA SANT~
REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
I I
WPR/ Cholera/9 16 April 1962 Manila, Philippines
16 - 19 April 1962
ENGLISH ONLY
m
roTLINES OF PREVENTION AND CONTROL PROGlW+SE
JA:PAlV AGAINST PARACHOLERA WE TO EL TOR v:mRIOS
1961-1962 by
Dr.
s.
Iwata1
Chief, Quarantine section, Public Hea.l.th Bureau, Ministry of Health and Welfare, Tokyo, Japan.
J.
WPR/206/62
, WPR/ abOlera/9 Pagel
1. 1.2 Scientific background
The Ministry of Health and Welfare established the "camnittee for Prevention of Cholera Invasion" (Chairman, Dr. Keizo Nobechi) consisting of the scienti~ts and the experienced concerned last fall, and referring to their opinions, the Ministry is forming their policies in regard. to the measures to prevent the invas ion of the new type cholera, prevailing in the South-East Asian Territories. The Ministry also requested the standing "Committee on the Diagnostic Method of Cholera Vibrios" (Chairman, Dr. Hideo Fukumi) to revise the present standard diagnostiC method to accord with the new situations. In connection with the pa.racholera due to Vibrio El Tor according to WHO, these committees are so far of the Views as follows:
1.2.1 About 65 epidemic strains of outbreaks of the present new type cholera epidemics were secured fram different South-East Asian Territories, namely : 10 strains of Celebes cases frClll Dr. TanemaJ, P.H. laboratory,
Makassar 9 strains of Java cases fram Dr. Sumlatno, Pasteur Institute, Bandung
3 strains of Sarawa.k cases fram Dr. Singh, I.M.R., Kuala 8 strains of Hong Kong cases framDr. Alvarez, Government Institute of Pathology and Quarantine SerVices, Hong Kong 1 strain of Philippine case indirectly fram U.S.N.M.R. Unit No.2, Taipei 34 additionaJ. strains of Philippine cases secured fram Ministry of Health
Wmpur
..
Comparative bacteriological examinations of these strains with those of the nationaJ. type cultures of cholera Vibrios were independently carried out by the NationaJ. Institute of Health, Institute of Infectious Diseases, Quarantine Station laboratories (Yokohama, Tokyo Airport and Tokyo) and Hyogo Prefectural Public Health laboratory. The results, thus, obtained were practically concordant. Namely all of the abovementioned strains were found to display microscopical, cultural and biochemical findings equal to what the cholera type culture strains did, except the results of baemolysin and Voges Proscauer tests. In the baemolysin test, follOWing Greig Method, the epidemic strains unanimously revealed the positive results, whereas the cholera type culture strains, the negative. In the case of V-P test, while the latter reacted negatively, the former discordantly or irregularly. It was further ascertained that iDmunologically, all epidemic strains, except one out of 10 Celebes strains and 2 out of 34 Philippine strains, which were found to be of "Inaba" type, belonged to the "Ogawa" type, as had been informed by Drs. Tanamal, Singh and Alvares to us.
, WPR/ Cbolera/9 Page 2
Thus, tbrougb tbe bacteriological examination of 65 epidemic straine by the Japanese Researcb Workers I own bands, it was clearly proved tbat the present epidemics, whicb is still prevailing in tbe Soutb-East Asia, bave been due unitarily to the El Tor type vibrio, mainly of the "Ogawa" subgroup, althougb WHO reported as i f they were dualistic epidemics due to cholera vibrios (Sa.rawak, Macao and Hong Kong) and El Tor type vibrios (the rest of the affected areas).
Ba.siDg upon the above-stated fact and the timely sequence, it is presumed that the present epidemics must have been originated fran Celebes and spread first to Java, then to Sa.rawak, and further to Macao, HOIlS Kong and Continental Cb1na., tbence to tbe Pb1l.ippines, and finally to Nortb :Borneo, directly or indirectly. 1.2.2 Because of tbe fact that paracbolera according to De Moor, used to show only small scale endemic upheavals confined to the Southern Celebes, it was resolved, at the 1958 meeting of tbe CCIIIIIlittee on International Quarantine, to be excluded fran the term "Cholera" under the International Sanitary Regul.ations. However, the present epidemic bas unmasked this disease, and disclosed its hitberto unknown nature as follows: Firstly, it is able to given rise to a quite extensive epidemic of international scale extending to several countries. Secondly, under circumstances, it can entail quite significant epidemics to cause even over ten thousand cases as in the case of the Philippine epidemic. Thirdly, the fatality rates suppressed through the practice of the up-to-date therapeutic method experienced in Hong Kong and the Philippines as to this disease were nearly equal to tbat of the autbentic cholera cases under the same condition in the recent Thailand epidemic. Since such icna.te character of tbis disease to be able to arouse serious events as enumerated above have been made known, it should be pertinent to include it in the term "Cholera" in the International Sanitary Regulations, erasing tbe definition proposed by the Committee on International Quarantine in 1958. 1.2.3 As stated above, all of the afore-explained 65 strains, except one of 10 Celebes strains and two out of 34 Philippine strains, 1nrmmologically belonged to tbe "Ogawa" type. The three exceptional strains were of the "Inaba." type, as labelled by Dr. Tanama,), and according to Professor Biran, Djakarta University Medical Scbool, an El Tor type strain bad been isolated fram a child case in Djakarta City during 1957 epidemic in the Celebes. Furthermore, De Moor reported that 7 strains out of 370 epidemic strains of 1937-38 and 1939.40 Celebes epidemics beloDged to the ''Hikoj:lma'' type. Thus, the El Tor type vibrios originating fran South Celebes, not only possess the antigenic construction correspondiDg to those of the 0-1 group, but also tbey were seen to be provided witb the peculiar inherent mutability into three :I.DJnunol.ogical types, munely fran the "Ogawa" type througb ''Hikoj:lllla." type to the "Inaba." type and vice versa., canpletely conforming with the a.uthentic cholera vibrio.
.t
WfP/ Cholera/9 Page
3
Therefore, it is scientifically most logical to regard the El Tor type vibrio as a haemolytic variant of cholera vibrio, and to refer to it as 'Vibrio camma, vax. el tor". 1.2.4 The term "Paracholera" bas long been accustemed to denote the sickness due to vibrios of O-II - IV groups. And so the serious disease, clinically nothing different frem the authentic cholera, however, caused by the haemolytic variant of cholera vibrio, should scientifically be called "Cholera" also, and not "Pa.racholera ", just like 10 the case of diphtheria. In the case of the latter disease, it is unanimously called as ''Diphtheria'', irrespective of whether they are due to the non-baemolytic gravis type germs or those of the haemolytiC mitis type. Furthermore, the appelation of ''Paracholera'' is to be avoided, because it may give the public such impression, as if not as serious disease, liable to lead to unconsciousness toward this disease. Administrative background 1.3.1 In our country the first epidemic of cholera was reported in 1822, and since then we bave suffered over ten t:!mes of cholera epidemic including the widespread epidemic in 1862 and also the one in 1946 introduced by repatriation ships (refer· to attached paper No.1). According to ma.ny reliable reports almost all of these epidemics were f'0W'ld to be due to cholera vibrio :llIlported frem other countries. In other words, cholera has not been an endemic disease in our country and, therefore, we can say tbat any epidemic of cholera in our country which is cempletely surrounded by the sea can only occur through importation of cases fram foreign countries. 1.3.2 All of the above~ntioned epidemics due to importation came frem the . aouthern part of Asia. Usually the cholera which originated in India sprea& eastward to the southern part of the Chinese Continent, and afterwards, canes to our country through Hong Kong and Shangbai or through Ta.kao and Keeling of Formosa. Also there bave been several cases transmitted directly from Java and the PhUippines. 1.3.3 We bave a close trade relation with countries of the southern part of Asia where they are at present suffering fram the epidemics of the WHO-d.efined paracholera due to El Tor vibrio. Frem countries of southern part of Asia a large n\.UDber of Japanese ships and foreign ships are coming to all harbours of our coast, and also many planes are ccming mainly to the Tokyo International Air Port. (Refer to attached Paper No.2). This fact, therefore, accelerates the danger of importation of the disease into our country. 1.3.4 The series of cholera epidemics in Southern Asian area in 1961 seem to have developed into such magnitude while sufficient measures were not taken because of such unrealistic consideration on the difference of bacteriological type and epidemiological character fran those of cholera vibriO, and also because of hesitation in ts.king emergency policy.
WPR/ Cbolera/9 Page 4
Where preventive measures were taken treating the epidemic as that of cholera, tbey~were able to check the epidemic with the least casualties. Our country under these considerations, had to take a quick decision for establishing emergent preventive measures. 1.3.5 In an international and domestic vacuum in which we cannot cODduct the sdtable domestic and international preventive measures against cholera for the present epidemic of WHO-defined pe.racholera due to El Tor vibrio, it is obvious that once there is an invasion into our country, we would suffer fran severe epidemic as in the case of the southern parts of Asia. If this should happen the epidemic wouJ.d be a threat to the security of the Japanese peoples' lives, safety of transportation and d.evelopnent of our econcmic programme, and eventua.lly to the maintenance of trade and friendly relationship with countries of the southern part of Asia. EspeciaJ.ly what should be noticed in this connection is that we have along the coast of the Japanese Islands, approximately 20 million inhabitants at present, and the possible danger for these peoples is too great to be ignored. 1.3.6 The eradication or control programme for communicable diseases being transmitted by international traffic cannot be successfully carried out by one country alone, and for the success of the programme, a close international collaborative work is absolutely necessary. UDder such circumstances it was thought to be appropriate, also fran the standpoint of international. trust and justice, that we should strengthen the quarantine measures and make a strenuous effort to prevent spreading of epidemics not only for our country, but also for the other countries.
2. Intensive Cholera Control Programme, 1961-1962 2.1 2.1.1 Quarantine measures a) revent invasion
To encourage notification of information concerning health conditions of ships and air crafts before reaching the quarantine area.
b)
To give attention to doings of ships and aircrafts in epidemic area, especially loading conditions of food, drinking water and others. To perform inspection of health conditions of seamen and passengers, especially early finding of diarrhoeal patients among them. To perform inspection of valid international certificates of vaccination for cholera for seamen and passengers. Preparations of materials, equipment, facilities etc. which are necessary for bacteriological examinations and other quarantine measures. Dissemination of information on the correct knowledge of cholera to travellers who are .proceeding to the epidemic area.
c)
d) e)
f)
2.1.2
Sanitation and control of port areas a) b) c) Cholera vaccination for workers in the sea and airports (refer to attached paper No.3). Investigation of contamination of sea water in the sea ports. Examination of drinking water in ships. Rodent control, including examination of carrier. Insect control. Sanitation and control of sea areas of ports. Disinfection of public lavatories and unhealthy areas. Dissemination of information on the current knowledge of cholera to the residents of port areas.
,
d) e) f) g) h)
-f ....
-. 2.2 2.2.1 Intensification of outbreak within the Immunization a) b) 2.2.2 About 600 000 persons, mainly in selected flort areas (ccmpulsory) About 400 000 persons, seamen, police, defence forces, etc. in addition (recommendation) ation for an
Organization a) b) c) Special units for cholera control at prefecture level.
Expert committee and national level. As
inter~inistral
liaison committee at
well as at prefectural level.
2.2.)
Reporting and laboratory examination a) b) Refresher courses Provision of diagnostic sera
2.2.4
Insects and rats control a) Selected port areas
2.2.5
Intensification of environmental sanitation a) Intensified inspection of water supply and food handlers in selected areas
2.2.6 2.2.7 2.2.8
Reassurance of isolation facilities Reservation of about 5 000 000 doses cholera vaccine for emergency use Health education
Paper No.1 Number of Cases and Deaths for Cholera in Ja:pa.n
(1877-1961) (Annual Report of Health Statistics) Ministry of Health &Welfare Ja:pa.n
Years
: No. of
: No. of :
: Cases
: Deaths : Years : Cases
: No. of : No. of . :No. of : Deaths . Years : Cases
: No; of
: Deaths
1877 1878
1880 1881
18'79
1882 1883 1884 1885 1886 1887
: 13 816: 8 902: : : 162 637 :105 1 580: 9 38) : 6 51 631 : 33 13 : 155 1 46 11 904: 824 : 9 923 :108 228 811 751: 019 : 35 142 7 874 633 546: 144 : 40 481 8)4 655 83) 377 101 8)1 8 172 1
6&)
1888 1889 18)0 18)1 18)2 1893 1894 18)5 18)6 18)7 18)8
55 1
1899 1900 1901 1902 1903 1904 1905
12
027 275 786 618 237 784 '+34 417 33) 405 654 410 431 227 760 497 3et 314 154' 907 488 374 487 .. 012 139 48 34
: §
: : : : : : :
1906 1907 3 632 1908 652 190':1 328 1910 2 849 1911 9 1912 2 614 1913 87 1914 5 1915 : 1916 : 10 371 1917 8)4 1918 407 1919 496) 1920 3): 1921 1922 743 : 4 : 1923 : 1924 624. 2 19 5 1926 25 2 1927 1 1928 193) 205 1930 1931 4. 1932 : 1933 : 1934
1 1 1
7
3
..
.. ..
3) 1935 702 1936 3)7 1937 1938 158 656 1939 35 : 1940 763 " 1941 106 1942 100 1943 63 19 4 5 482 1946 1947 718 1948 32 1949 356 417 1950 1951 35 542 1952 31 195:5 1954 1955 1956 1957 1958 1959 1960 1961 J.
57 18
II
10
1 24·5
.. .. .. .. ..
..
1 ~
• .. .. .. .. ..
.. .. .. .. .. .. .. ..
..
•
Paper No. 2 Number of Aircra.f't and Vessel which Arrived fran Hong Kong, Macao, Ph:Uippines, Indonesia and North Borneo during 1961 Name of Port or Airport otaro Kushiro Rumoi HakodAte Muroran Aanori Hachinohe To~o
-y
:No. of inspected :Hong Kong :Ph11ippines :Indonesia.: North Borneo :vesse1 or air- :and Macao: craft 131 123 13 127 335 8 22
27
3 5 27
10 1 6 12 1 265 7 4 * 1 :
3 10 10 11 --:
4 81
r--. '. i
Kama.ishi Mima.lw Shiogama. Onabama.
1119 144 2j 18 5912 3 626 327 74 257 216 16 28 25 537 39
-
5
*1 839 2j2 3
....
Airport Yokohama. Yokosuka Misaki Niiga.ta. Fushiki Toyama. Funakawa.
To~o
*
-
3 * 1
2
81.6 214 9 16 1 4 1 54 192 22 6 220 10 2 440 6 35 4 10 10 1 1 85 40 14 5 12
157 3 2
49 1 6 6 3 11 18
10
5
Sakata. Nanao Slrlmizu
20
"'" ..Jo.. .....
-
J.
..... ...
"
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Yaizu Nagoya. *1 680 Yokkaichi 344 40 Tsuruga. 1 284 Osaka. 326 l'1aka.yama. Shimotsu Maizuru 97 * Osaka. Air Port 350 2 074 Kobe 46 Sakaide 126 HiroslUma. 111 Kure Niihama 93 32 Sal'2.i Matsu;yama 137 3467 Moji 116 *3 Iwakuni 322 Tokuyama Klldamatsu: 1 Wakamatsu 118 Tsukumi 10 Saiki 236 Ha.ka.ta. Izuha.ra 7'J3 Itazuke * 165 Miike 55
44 26
.
16 3 23 16 75
68 7 7 106 13 4 32 12 2l 14 15 5 1 6 1
100 7 3 719 10 7 10 2
5 13 34 39 27 20 3
354
... -: .
2
14 3
-
*
1
-
7
*
Aircra.f't •
Paper No. 2 Page 2 :No. of' inspected: : vessel or air- :Hong Kong :Pbilippines : Indonesia :North Borneo craf't :a.td Macao: r ,
Name of' Port or Airport Karatsu Sasebo Nagasaki Misumi
Kagoshima. Naze Hososh:ima Yoron Total
*00
55 24 5 237 120 206 120 37 218
2
3
2
1
27 9-
: 1 7(1) :* 1 8:11
..
9 46 9 1 7
3 4 2 ~
1
1
25 5 1 1
.....
18931 * 6491
~ ~9
()+7
*
494 1
549
.-. ,
1
"
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}_ "I
, I , ,
II
II
II
I
.r-~~-----------------------------------------------------------------.
FIGURE III - CHOLEM lliJMUNIZATION AREAS IN JAPAN JANUARY - MARCH, 1962
(.)
INDICATES SELECTED PORT AREA
WORLD HEALTH ORGAN I ZATION
ORGANISATION MONDIALE DE LA SANT~
REGIONAL OFFICE FOR
THE WESTERN PACIFIC
BUREAU REGIONAL DU PACIFIQUE OCCIDENTAL
MEEn'mG FOR '!'HE EXCHANGE OF mFORMATION ON EL TOR VIBRIO PARACHOLERA Manila, Philippines 16-19 April 1962
WPR/ Cholera! 10 16 April 1962 ENGLISH ONLY
I
\
Scm: BIOlODICAL AND SEROLOGICAL CHARACTERISTICS OF '!'HE VIBRIO STRAINS FORWARDED TO US FRGi VARIOOS PLACES m SOOTH ASIA AS THE CAUSATIVE AGEm' OF THE SO-CALLED "PARACHOLERA" by
Dr. H. :FUkumi1
"
J,
lDepartment of :&.cteriology I, National Institute of Health, Tokyo, Japan. Wffi/204/62
. WPR/Oholera/10 Page 1
GREIG HEMOLYSIS TEST: strains Kuching Kuching 886 Kuching 900 Incubation 4 hours at 37tJC OVernight after the preincubation at 37"c
f
~
~ f OVernight at refrigerator after the preincubation at 37°C
Incubation 2 hours at 37° r'"
"-
,
Java Java Java Java Java Java Java Java Java
1
3 4 5 6
j j.
7 8 9 10
j ~ f ~ j OVernight at refrigerator after the preincubation at 3~C
Incubation 3 hours at 37 cc Hong Hong Hong Hong Kong Kong Kong Kong 1 2 24 25
~ ~ f
j ~ f
New Territory Mainland 50
.....,.....
New Territory Mainland 51 msroRY OF Sl'RAINS Strains Kuching Kuching 886 Kuching 900 Java Java Java Java Java Java 1 3 4 5 6
Serotype Ogawa IT IT
History from I:1stitute of Medical Re search, Kuala LUlIl.J?ur, Malaya isolated from Bandong (west Java) IT
Ogawa IT
" IT
Tjiandjur (West Java) IT
--
7
" IT
purwakarta (west Java)
"
WPR/Cholera/l0 Pace 2
HISTORY OF STRAINS (cont I d) Strai ns Java 8 Java 9 Java 10 .~
Serot ype Ogawa II II
Histo ry isola ted from Tjireb on (\vest Java) SwmaranC (Middle Java) II
r
Hong Hong Hong Hong
Kong Kong Kong Kong
1 2
Ogawa II
24 25
" "
isola ted on August 17, 1961 from patie nt II 18, 1961 23,19 61 " 24, 1961 " isola ted on August 29, 1961 from a carri er
New Terri ty Mainl and 50 Ogawa New Terri ty Mainl and 51 "
"
,-.... . ~
lfPR/Cholera/l0 Pace
3
GREIG hemolysis test was made for the following authentic cholera vibrio strajns by using 24 hours', 72 hours' and 7 days' cultures. Greig hemolysis test was carried out with the incubation period of 2 hours at 37vC and thereafter overnight at refrigerator temperature. Noiccolytic reaction was recoGnized for all the strains employed. stro.i.ns Inaba (protype) yanagihara Ogawa (protype) Kamata 1102 Ura 12 Ura 13 Ura 14 375 Serotype Inaba Inaba OGawa OgaYT8. Ogawa Ogawa Ogawa Ogawa Inaba It It It It
History isolated in 1913 in Japan It It 1916 It It 1913 It If 1946 It It 1942 It It 1946 It It 1946 tt It 1946 received from Central Research Institute, Kasauli, India It
384-
;1)3 ;1)9
" tt
420 )68 378 425 556
Ogawa tt
"
" tt tt tt tt
558 ~-
"
"
chogen Cho-i J\J.
Inaba Ogawa Ogawa tt It It
received from Korea after the war
" tt It It
tt
tt
It
. ..
recei ved from Thailand It It It
...
AIl BI BII 11
lnaba II
14 47
received from Central Research Institute, Kasauli, India It It It It
Ogawa It It It
69
70 71
vTPR/Cho1era/10 PaGe 4 AGGLUTINATI ON REAarION.
Sera: rabbit immunized with antigen heated at 1000 C for 2 hours. Antigen for agglutination reaction: heated at 100°C for 1 hour. Antigen ~
lnaba antiserum (titer:2560) KUching KUching 886 Kuching 900 Java Java Java Java Java Java Java Java Java 1 3 4 5 8 9 10 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 2560 1280 1280 2280 1280 640
OGawa antiserum titer:5120) 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 5120 160 5120 )120 5120 5120 5120
KUch1ng 886 antiserum (titer:1280) 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 1280 640 2280 1280 1280 1280 1280
I
"
6 7
Hong Kong 1 Hong KonE, 2 Hong Kong 24 Hon" Kong 25 Nel. Terri tory 50 New Territory 51 Celebes
" "
" "
" " " " "
1 2 3 4 5 6 7
8
10
9
The f'e:ra em;p1oyed were not absorbed.
WPR/Cholera/10 page 5
History of strains egployed:
strains Celebes Celebes Celebes celebes Celebes Celebes Celebes Celebes Celebes Celebes 1 2 3 4 5 6 7 8 9 10
serotype OGawa
Original No. 8899 8900 9029 9110 9162 9835 12714 12885 12925 13708
Date of Isolation 31 31 2 4 5 29 31 4 6 7 1961 July 1961 July August 1961 August 1961 Au,;ust 1961 Augusil 1961 october 1961 November1961 November1961 November1961
Isolated from corpse
,1<
Inaba OGawa
" " "
"
" " "
patient corpse patient
" " "
"
"
"
Agglutination Reactions with Absorbed Sera: Antigen Kuching 886 Hong Kong 1 Celebes 1 558 (authentic Ogawa) 384 (authentic Inaba) Antigen 558 (authentic OGawa) Kuching Kuching 886 Kuching 900 Antigen Kuching 886 Kuching 900 Kuching Kuching 886 anti-serum absorbed 'nth authentic cholera vibrio 555 (Ogawa type) 1:10 1:10 1:10 1:10 1:10 -
Ogawa anti-serum with kuchinb 886 1:10 1:10 1:10 1:10 Inaba serum absorbed with Ogawa 1:10 1:10 1:10 Ogavla serum absorbed vith Inaba 1:640 1:1280 1:640
J
WPR/Cholera/10 pa&e S Alltali agglutination reaction: Serum employed: rabbit antiserum a8ainst Oga'la strain, containin8 merthio1ate as preservative at a concentration of 1:10,000 (final concentration). Agglutinin titer of the serum was 1:5120 aGainst Ogawa strain in the usual 8~1utination reaction. .\lkali agglutination titer 1:40 1:40 1:40 1:1280 1:2560 1:2560 1:2560 1:2560 1:2560 1:2560 1:2560 1:51120 1:5120 1:25EO 1:5160 1:2560 1:5120 1:2560 1:2560 1:2560 1:2560 1:5150 1:2560 1:2560 1:2560 1:1280 1:2560
Strains Ogawa 420 (authentic Inaba) 558 (authentic Ogawa) Kuching Kuching 886 Honb Kong 1 Hong Kong 2 Java 1 Celebes 1 Hong Kong 29 Kowloon lZ}5 Hanila 291 Philippine 1 2
, "\
Phil. 16
10 11 12 13 14 15
3 4 5 6 7 8 9
Alkali agGlutination titer 1:2560 1:5120 17 1:2560 18 1:80 19 (Inaba) 1:2560 20 1:2560 21 1:2560 22 1:2560 23 1:2560 24 1:5120 25 1:2560 26 1:2560 21 1:2560 28 1:2560 29 1:2560 30 51 32 33
34
1:2560 1:2560 1:2560 1:2560
The strains Hong Kong 29, Kanton 1235, and Manila 291 were received from the U. S. Navy at yokoswca, J~Fan.
.
. ,-
WPR/Cholera/10 page 7 SUGAR FERMENrATION: strains Inaba Ogawa 420 556 558 Ura 15 Arabinose Lac~.)se
11annose
Succhurose
Salicin
384
1:4 ~J /-7 /-. /-7
j ~ f ~ ~ t ~ ~ ~ ~ l~ ~ ~ ~ /-3 f
,...., ""......
AI
Kuching Kuching 886 Kuching 900 Java 1 5 4 5 6 7 8 9 10 Hong Kong 1 2 24 ~'" r #"
1-5 • l1-.3 /-5 /-.3 /-.3
j ~ ~ ~ ~ f. ~ ~ ~ ~ I-
I
~
-
-
1-3 /-.3 /-3 /-.3 /-.3 /-3 1:3 /-.3 /-3
~ ~ ~ ~ I ~ ~ ~ ~ I ~ ~ ~ ~ ~
,-.,..,.
"-
New Territory 50 New Territory 51 Hong KonE, 29 Kanton 1235 Manila 291 Celebes 1 2
...
~ ~ ~ ~ l-
8 9
3 4 5 6 7
1-3 1-3
10 4.-
1:3
.~
j ~ j
~
j ~ ~ ~ ~
·
-
WORLD HEALTH ORGANIZATION
ORGANISATION MONDIALE DE LA SANTt
REGIONAL OFFICE FOR
THE WESTERN PACIFIC
BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
MEEl'ING FOR THE EXCHANGE OF INFORMATION C~ E"L TOR VIBLUO PARA-CHOIERA
WPR/Cho1eralll 16 i\J?ri1 1962
Manila, Philippines 16-19 A;pril 1962
ASPEOl'S OF CLINICAL MANAGEMENT OF PARA-CHOIERA PATIENl'S
,..,
by Craig K. Walp-ce LCDR Me USNR
1
Hailing address:
U.S. Naval Medical Research Unit No.2, Box 14, APO 63, San Francisco, Cd.lif'ornia
WPR/Cholera/ll Pa,:je 1
From the United states Naval Medical Research unit No.2 (NAMRU-2), Taipei, Taiwan. This study has been s1,lpported in part 'uy fundinG under public La., Section 104 (c).
480,
The opinions and assertions contained herein are those of' reflectin~
the author and are not to be construed as official or of the Navy Department or the Naval Service at large.
'"
the views
The clinical manifestations in patients vi th El Tor cholera or classical Asiatic cholera are identical and therefore the treatment the same. MOrtality rates in an untreated popttlation during a cholera epidemic generlly are stated to be about sho~d
be
60 per cent. (1) In some small Groups the
mortality may be 100 per cent and in others the disease may be manifested by only a mild diarrhea.(2) In the Philippine Islands from September 1961
until 3 March 1962, there were 14,189 cases ,rith 1,998 deaths, an overall mortality rate of 14.1 per cent.(3) At Manila's San Lazaro Hospital, from
the onset of the epidemic until 12 October 1961 there "ere 143 admissions
.' with 20 deaths, a mortality rate of 14 per cent. After the in~Groduction
of
our therapeutic reGimen, the mortality rate from 13 October 1961 t,hrough 1 March 1962 'liaS ).4 per cent (526 admissions vith 18 deaths). (Slide 1)
These figures substantiate our conviction that death from cholera can be prevented by raFid and adequate correction of the severe electrolyte losses. Intelli~ent
dehy~~ation
and
treatment of any clinical entity necessitates an understandThe severe fluid and electrolyte losses in the
ing of its pathophysiology.
HPR/Cholera/ll Pace 2
massive diarrhea of cholera have been Immm qualitatively for over 100 years. (1)
(4) In 1~09
ROGers
documented the tremendous losses of sodium, chloride and He did not deterndne the electrolyte concent-
potassium in cholera patients.
rations of the stool 1Tater nor did he draYT serial blood samples from the few patients studied. He concluded erroneously that the blood vas llypotonic and
that the replace;2en'c solutions should therefore be hypertonic.
(5)
InitiaJly,
he stated that parenteral potassium also vas necessary in therapy; seven years ,
,
later he retracted this statement, believinG that the administration of po-
(6) tassium might be physioloGically harmful. The ,Torl~
(7) of Saha and Das in sellards, working
1952 again emphasized the excessive loss of potassium ions.
here in Manila in 1910, first observed the larGe losses of bicarbonate ions. (8) Furthermore, Rogers and SCllards both 8u[Q;estec1 that the acio_osis in this disease should be treated.(5,8) DurinG the EGYPtian epidemic in 1947, lTANRU-3 workers ITere the first to relate fecal eletrolyte losses to plasma levels in the same patient. (9) They formulated a simple and successful theTalleutic reGimen based upon these data. (10) HO"lever, oral intake VTas not res-i;,ricted in their patients and there-
fore accurate determinations of fecal electrolytes could not be made. Hatten and h~s
_
NAMRU-2 co_workers
(11)
, during the BanGkol: epidemic in
1958, definitively related the concentration of electrolytes in plasma 'vater to the concentrations in stool water. ially isotonic. They found the dehydration to be essent-
For the first time, fluic1 and electrolytes "ere administered usin;:; balance techniques with frequent measure-
only by intravenous infusion.
i,lents cf intal;:e and output in the same pa-c,ient, fecal electroly'ce concentrations VTere shown to vaJ.'y vi th hourly stool volwile. If the G!D.rrhea occured at a rate
WPR/Cho1era/ll pa...;e 3
of 125 m1 or more per minute, concentrations of fecal sodium and chloride .,ere nearly isotonic with plasma, .mile potassium and bicarbonate ,Tere si1$nificant1y hi&~er.
As the hourly fecal
vo1~~e ~ecreased,
the concentrations
of sodium and chloride decreased, ,mile the concentration of potassium rose even higher, thus demonstratinG that both 1ar...;e and small vo1~ues
of diar-
rheal stool in cholera produce similar severed losses of electl'olytes. (Slide2) controversy as to the action of the orcanism in causinb massive diarrhea followed the isolation of the cholera vibrio by Koch in 1883. (12) Virchow
(13)
from 1879, had been the leading proponant of the denudation of the intestinal (14) mucosa theory. Cohnheim first denied "C~le denudation theol'Y and his work ,ms most ably supported by Goodpasture in 1923.(15 ) epidemic in Cairo(9) studies dtTing the 1947
~rovided
the first sicnificant indication that there ,ms At that time, Seitz-filtered A
no massive desquamation of the intestinal mucosa.
cholera stool was shown to contain less than 0.1 gram per cert ~rotein. transudate should contain about 2 grams per cent protein. dicated that there was little or no slo~1inL
These studies in-
of the intestinal mucosa to subsequently,
permit an outpourin[, of a tro ..lsudate in the cholera patient.
,
during the
Banolwl: epidemic in 1959, GanGarosa, (16) studyinG biolJSY speci-
mens obtained by a
Crosby capsule found t!lat the epithelium fror,) human inGordon (17)
testinal mucosa vas intact throu[)1out "Ghe course of the disease. provided the final prcof a 6 ainst the denudation theory polyvinylpyrrolidone (PVP) tagGed with Iodine throu~1
his use of
(151 )
•
PVP is a lar:;e :protein Gordon admdnistered in-
molecule that is not attacked by intestinal bacteria.
t ravenously the taGGed PVP to cholera patients and to healthy controls and found that the cholera stools contained no larGer quantity of PVP per unit
WPR/Cholera/ll Pa:::;e 4
time than the stools of normal individuals.
This was indeed conclusive evi_ However, the
dence against the theory of massive desquamation of epithelium.
preCise mechanism of fluid loss in cholera remains to be delineated. Durin::; epidenics of cholera, medical personnel, hospital facilities and supplies are often less than adequate. TherapJ' must be sll.lple in deSign, Such
it must be simple to accomplish and, of course, it must be efeective. therapy was developec, durin<.o the \
Cairo epidemic in 1947.(10)
The regimen was
(18) midified during the B~nglwl,"
epidemics in 19513, 1959 and 1960, and further modi.
fied in Manila last fall. (19) Adequately lar~e
and suitably equipped treatment centres should be Admission should be a simple pro.
available to patients Within 3 to 6 tmits.
cedure and a history of a copious, watery diarrhea is sufficient during an epidemic. upon admission the patient is weiC;,hed, and placed on a "cholera bed" which is an anny cot "lith a reinforced hole in the center about 9 inches in diameter. (Slide 3) ~
receptacle is placed under the hole and serves as an
effective means t.;):r collectine; all excreta ,lithout the frequent necessity of moving the patient or emptyinG and measurinu bedpans and urinals. stic!~s
Hooden
are marl:ed for each 500 r.U. so that satisfactory measurede,1ts of the It is necessary to ],eep a conA sheet of paper
amount of excreta may be rrade at any time.
stant record of fluid intake and output for each patient.
is attached to the cot, ,Tall or I-V stand and the time and. alllount of all in. fusions are recoroal as they are initiated. by using a "dipstick" and also recorded. The amount of excreta is estimated
WPR/Cholera/ll PaGe 5
A venipuncture is performed using a
It
18 or larJer gaU[;e needle '\-rhich
is left in place to provide a large bore for the rapid administration of fluids. Superficial aJ."1ll
veins are preferable.
A leG vein is less desirable because
of the hiGher incidence of thrombophlebitis ana. embolic phenomenon in the 10l[er extremities. However, there is frequently little dloice and in our experIn cases of severe
ience ,-re have seen no ill effccts fro ill usinG leg veins.
.-.: , ,
dehydration and/or shock we often utilized a femoral vein, a technique which allmlS blood :pecimens to be obtained
In. th
ease.
By hold in;:; the needle in
place, fluid may oe Given until a "cut-down" or a superficial vein can be utilized. The blood iJ2ecimen is then placed into a tube coateo. 111th either
heparin or oxalate nnticoagulant solution. An infusion of isotoniC saline is started immediately. should be administered The infusion
as rapidly as POSSible, preferably 100 ml per minute.
This amount may be siven uith impunity to elderly patients "'ith cardiac involvement or even children since the patients are to be rehydrated only to their usual physioloSic state. During the Ban::o!;:(18) and PhiliPPine(19)
,
epidemics, there vere no difficulties 1lith overhydrati. on. Complete history and physical examinations are time-consu!iunG and fre_ quently misleadinG in the cholera patient. Temperaiu l'e, pulse and "blood pres-
sure dctenninations as well as the state of sl.in tursor and mucous membranes do not provide a reliable indication of the patient's state of h:yclration. Laboratory studies for deteITilining blood C01.U1tS, urinalysis istries are not necessary. aile.
blood chem-
Results may indicate dehyfu'ution but cannot pro_ PhilJ.::r.s
vide the rapid information neccssary for hOUl'-oy-hOur manaGeuelTG. '1 ...
...
vlPRjCholerajn
Pase 6
and co_workers(20) have shown that the plasma protein concentration, as determined by the COppel" sulfate methods, is -chc most reliable Guide to the extent of dehydration. The copper sulfate method. is performed easily and The majority of cholera pa-
quicldy under the most primitive conditions.
tients havo craryin c , c.ec;rees of anemia and any determination involvinG hemoconcentration may be misleadinG. Initially, ve do not rely upon ,mole
blood specific Gravities, but rather upon plasma specific gravit.iez for the
..
true indication of the patient's state of dehydration.
Both \Thole blood and
plasma specific gravities are performed, hOi-leVer, so that subseqlcently the two values may be correlated. 1,Jhen the patient is rehydrated to a plasma
specific gravity of 1.025, his ,mole blood specific gravity is d.et.ermined and considered to be his physiol0 6 ic value. The amount of fluid replacement is and specific Gravity (Slide detel~uned
on the basis of weiJrrt
4).
This is a l~ue-of-thumb means for deterFor eXa!i"!ple, a 50 K.;
minint; the fluid required to rehydrate the p:x:;ient.
-, '-
adult, admitted _lith a plasma speCific
~ravity
of 1.035 would neec. 200 ml
(4 mljKg) of isotinic fluid for eacl1 0.001 elevation of specific Gravity above 1.025, i.e. 2000 ml of fluid. After the calculated amount of fllid for initial rehydration has -been C;i ven, the infusinn rate may be slo"ed to 3 - 10 blood specific ~ravity
,;ll
:ger minute.
The ,;hole
that will equate ,lith the plasma specific Gravity of This corrects for any discrepancy relatinG to
1.025 is then determined.
anemia or hemoconcentrati. on and obviates the necessity of further centrifUGuinc, blood for plasma specific gravity deterilunations.
.
.....
HPR/Cholera/ll PaGe 7
Once the patient is initially hydrated, his fluid state may then be con_ trolled completely. of outptrt. The amount of intal~e cnn cenerally be equated to the amount
ROI,ever, one also should consider the insensible iw:;;'er loss which has
been shown in a small series of cholera patients to be somevrhat ,..;reater than 1 ml/ KG/hr. (21) (Slide 5) vatten and Phillips (22) have stated that paralytic ileus
from hypolcalemia ivill occasionally cause sequestration of a lar2,e volume of diarrheal fluid in the bowel and may result in misleading estir.mtions of' fluid
,
loss.
These qualifications of fluid loss
est~nations
necessitate specific graThis pro_ As the
vity determinations every three to six hours after initial rehydration. vides a sufficient check to prevent any severe replacement discrepancy.
diarrhea subsudsides, the frequency of specific Gravity deternunation may be lessened. The type of fluid replacement that the cholera patient req1..cires is primar_ ily isotonic saline. Recently, Hatten and co_workers(ll) reponed that an aver_ They indicated that The bicarbonate
age of 45 mrqjL of bicarbonate is found in the cholera stool. for each mEq decrease of plasma CO2 belOi'T 25 rnEq/L, 0.6 mEq/L. "~
loss suggests the possibility of' a rather severed aCidosis and patients who are not infrequently occurs because of' the severe untreated acidosis. Treatment of a deIn the
hydrated child is ahTays critical and. is especially acute with acidosis. I
'. 'C
Philippines we used the ratio of 1000 ml of 2 per cent sodium bicarbonate to 3000 ml of isotonic saline.
These fluids vrere Given initially and Generally corrected He observed
the acidosis.
Determinations of plasma C02 vrere not necessary. vOLtittin~
that nausea ru1d
were practically nonexistent once acidosis was beinG
corrected and oral fluids could then be ';iven.
WPR/Cholera/ll Page 8
watten and Phillips(22) have discussed the necessity of potassium in the treatment of cholera to prevent renla tubular damage, myocardial depression and neuromuscular disturbances, such as paralytic ileus. They found that the ad-
dition of 10 mEq (0.75 gm) of KCI to each liter of fluid would replace at least half of the loss. ,.-.' As long as diarrhea persisted, they anticipated little dan-
ger of hyperkalemia since the fecal losses are approx:i.I!L'ltely 10 to 15 mEq/L. They stated that if the d~rhea
does not exceed 3 liters per 24 hours and does
~
,
'.
not last more than 3 days, intravenous potassium is not necessary in the uncomplicated case. There is little question of potassium loss but the depletion mal~e
'._. r'-
has not been sufficiently elucidated to
absolute therapeutic recommendations. stocl~
We do not recommend that potassium be incorporated into any
solution but
rather that it should be administered only opon the physician's recommendation in the individual case. During our recent experiences in Manila, we were unable
to obtain parenteral KCI and used, probably with less effect, an oral replacement. Oral supplements once tolerated, give an extremely favorably psychological benefit and possibly a therapeutic benefit. " The efficacy of oral fluids in Warmed
the therapeutic regimen, however, is an aspect that must be evaluated.
meat broth with supplements of bicarbonate and potassium citrate was well tolerated by our patients. A 5 per cent solution of sodium bicarbonate is pa2atTen ml of a mixture of 100 gm
able and may be added directly to the broth.
each of potassium citrate, potassium acetate and potassium bicarbonate per liter of H 0 may be given three times a day as recommended by Hatten and 2 Phillips (22) or may also be added to the broth. Tea
a~d rice gruel were grad-
ually introduced at San Lazaro Hospital until the patient was eating a soft diet.
WPR/Cholerajll page 9
The duration of intravenous theraphy ..Tas determined on the basis of three factors: 1) the termination of diarrhea, 2) the satisfactory ingestion
of fluids and a soft diet, ani 3) the ability to excrete a normal amount of urine (about 1 ml/Kgjhr). These are reliable indices that the patient has
no gross disturbances of either the gastrointestinal or genitourinary systems. It is co~venient
at this time to transfer the patient to a convalescent ward
where he may ambulate, imprOve his nutritional status and generally recuperate ,
"
away from the tempo of the acute ward.
Usually daily rectal swabs are obtained A convalescent patient was dis-
from patients for culture of the vibrio.(24) charged from Manila's San cultures. L~zaro
Hospital only after three consecutive negative
Our therapeutic regimen is based upon the physiologic replacement of the water and electrolyte losses in cholera patients. is self limiting, therapy is dire~ted
Since the disease process
to maintenance of the patient until his There is no indication for other Such therapeutics are not
physiologic processes are re.established. ,~
vasopressor agents as well as cardiac stimulants.
directed at the true cause of shock which is the need for fluid replacement •
....
Furthermore, the effect of th&se drugs mic;.'lt ;lell cause additional ischemic damage to kidneys, adrenals, brain or liver, and may lead to irreversible changes in a patient already experiencing maximal physiologic response to hts dehydration. lie have encountered advocates of colloid plasma.volume expanders Glucose was frequently recommended and
and other types of fluid replacements. given.
Obviously, this is undesirable since the large quantitiBs of glucose
solutions necessary to rehydrate the cholera patient would markedly raise 1:he blood glucose level and obligate the kidney to eliminate S1.lg8.l'.
The anuria
WPR/Cholera/ll Page 10
which is the patient's response to his dehydration is so reversed that even additional water and essential electrolytes are eliminated. We do not recommend the use of sulfonarnides or antibiotics. Although
many of these drugs are bacteriocidal for the vibrio, there is no evidence that their use affects the pathogenesis or prognosis of this disease. Slide Slide
6. 7.
WPR/Cholera/ll Page 11 REFERENCES 1. 2.
Pollitzer, R. Cholera. World Health Organization Monograph Series No. 43, Geneva, 1959. Re:iJna.nn, H. Cholera in: Current Therapy. Philadelphia and London, 1962. vl.B. Saunders Co.,
3. 4.
Weekly Disease Intelligence Center Bulletin, Department of Health, Manila, Vol. 1, No.9, 8 March 1962. Rogers, L. The variation in the pressure and. composition of the blood in cholera. Proc. Royal Soc. B. 81: 2<:9, 19 <:9 • Rogers, L. The treatment of cholera by injection of hypertonic saline solutions with a simple and. rapid method of intra-abdominal administration. Philipp.J.Sci. (Sect. B) 4:99, 19<:9. Rogers, L. The further reduction of the mortality of cholera to 11% by addition of atropine hypodermically to the hypertonic and permanganate treatment, with an addendum summarizing the system for treatment. Indian Med. Gazette, 51:7, 1916. Saha., H. and ras, A.
.
5· '.
6.
7. 8.
Observations on the nature of cholera stools. J. Indian Med. Asso., 21:464, 1952. Philipp.J.
Sellards, A.W. Tolerance for a.lka.lies in Asiatic cholera. Sci. (Sect.B), 5:,63, 1910.
9. 10. 11.
Weaver, R.H., Johnson, M.K. and Phillips, R.A. Biochemical studies of cholera. J. Egypt. publ. Hlth. Ass., 23:5, 1940. Johnson, M.K., Weaver, R.H. and Phillips,R.A. J. Egypt. publ. Hlth. Ass., 23:15, 1948. The treatment of cholera.
Watten,R.H., Morgan, F.M., SongltliLa, Y. na, Vanikiati, B. and Phillips, R.A. vlater" and electrolyte studies in cholera. Invest., 38:879, 1959.
J. C1in.
12.
Koch, R. Vierter Bericht des Leiters der deutschen wissenschaftlichen Commission zur Erforschungder Cholera, Geheimen RegierungsBaths Dr. Koch. Dtsch. med. Wschr. 10:63, 1884. Vir chow, R. Gesammelte Abhandlungen auf dem Gebiete der offent1ichen Medizin, Berlin, vol. 1, p. 151, 1879. Cohnheim, J.F. Lectures on general pathology ""- a handbook for practitioners and students, London (translated from the 2nd German edition by HcKee, A.B.) 1(0)..1)0. Goodpasture, E.W. Histopathology of intestine in cholera. Sci. (Sect.B), 22:413, 1923. Philirp.J.
13. 14.
15·
· ...
'. 1fPR/ Cholera! 11
Page 12 16. Gangarosa,E.J., Beisel, W.R., Benyajati, C., Sprinz, H., and Piyaratn, P. The nature of the gastrointestinal lesion in Asiatic cholera and its relation to pathogenesis: A biopsy study. Am. J. Trop. Med., 9 :125, 1960. Summary of SEATO Conference on Cholera. 76:323, 1961. Public Health Reports,
17. 113.
Morgan, F.M., Watten, R.H., Bidyabhed, L.B., Vejasakdhi, L.P., Bangxans, E., na, and Phillips, R.A. Treatment of cholera. J. Med. Ass. Thailand, 42:413, 1959. Uylangco, C.V., ~.yallace, C.K., Cox, J.V1., Fabie, A., Primicias, P. and Phillips, R.A. The treatment of cholera. In press. Phillips, R.A., Van Slyke, D.D., Hamilton, P.B., Dole, V.P., Emerson, K. Jr., and Archibald, R.M. Measurements of specific gravities of "'hole blood and plasma by standard copper sulfate solutions. J. Bio1. Chem., 183:305, 1950. vTatten, R.H., Blaclwell, R.Q. and Phillips, R.A. The relation of electrolyte concentrations in plasma and excreta of cholera patients. SEATO Conference on Cholera, Dacca, East Pakistan, 5-8 December 1960. Watten, R.H. and Phillips, R.A. Iancet, 999, 1960. Potassium in the treatment of cholera.
19. 20.
21.
22. 23.
Watten, R.H. and Phillips, R.A. Cholera: Physiological alterations and their correction. U.S. Naval Medical Research Unit No.2 Lecture and Review Series, Report No. 6p~2, 1961, and presented at the Annual Meeting of the Association .of Military Surgeons of the United States, Vlasbington, D.C., 1 November 1960. Uylangco, C. V. Personal connnuni.;ation.
24.
WORLD HEALTH ORGANI ZATION
ORGANISATION MONDIALE DE LA SANT~
REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
MEEWLNG FOR THE EXCHANGE OF INFORMATION ON EL TOR VIBRIO PARACHOLERA
17 April 1962
Manila l Philippines 16 - 19 April 1962
A REPORT ON THE CHOLERA OOTBREAK IN SARAWAK
1961
page 1 1. INTOODUCTION
Cholera is one of the six quarantinable diseases under the International Sanitary Regulations. In July 1961, Sarawak was startled to find that what appeared to be a Virulent form of this disease had suddenly appeared in Kuching after an absence of fifty-nine years, the last outbreak having occurred in 1902. In the pages that follow, an attempt is made to set down varibus interesting aspects of the outbreak, and the methods employed to bring it under control. It must be emphasized that the type of cholera ubrio:was not identified until October 1961, when it was proved to be a parachl>lel'a strain of the El Tor variety. 2. GENERAL INFOIf1A"nON ON SARAWAK
Sarawak lies between latitudes 0 0 50' and 50 North and longitudes lOsP J6' and li5° 40' Eas t, occupying mos t of the northwestern coastal area of the island of J:Iorneo. With an area of about 47 500 square miles the terri tory covers a little less than one-sixth of the island, which is the third largest in the world and the largest of the 3000 or more i.~ands comprising the East Indies Archipelago. The boundary between Sarawak and Indonesias Borneo follows the watershed between the rivers flowing generally northwest into the South China Sea and those fiowin(' southeast into tba Celebes and the Java Seas. Although much of this watershed is not particularly high the country is generally rug/!ed and topographically canplex, and the boundary is unsurveyed. Because of the almost continuous presence of heavy cloud, part of this boundary and the adjoining Sarawak terri tory have not yet been covered by satisfactory air photography and only preliminary reconnaissance mapping is available. In the north, Sarawak adjoins North Borneo and in the northwest the State of Brunei forms a double enclave. The boundaries between Sarawak and these two countries run through much easier country and sections have been surveyed as the need has arisen see Appendix I. Mount Murud, of about BOOO feet, is Sarawak's highest mountain, dominating an area of practically unexplored raVines, plateaus and involved mountain ranges rising to over 5000 feet. Knowledge of this area has been gained by Visual reconnaissance from Royal Air Force aircraft and by various expeditions, notably those of the Sarawak Museum, Geological Survey Department and the Oxford University Expedition to the Usun Apau Plateau region in 1956. The remainder of the country comprises an alluvial coastal plain a belt of undulating country separating the coastal plain from the sharply rising mountainous interior. The coastal plaiR varies in width from less than a mile at Miri to over a hundred miles elsewhere and IiI:d
~
r-..
page 2 cont~·_r:i'JlE.l'ge areas of peat swamp of various depths. The beaches are generally of mud and mangrove or nipah palm. The belt of undulating country is broken by a few mountain groups, generally not more than 2500 teet in height, Shallow coastal waters and the existence of bars at river mouths limit the development of deep seaports.
(
The main rivers rise in the interior ranges and flow fast through deep gorges and over numerous rapids until they reach the undulating country and the coastal plains, where they meander towards the sea. In spite of the high rainfall and the steepness of the interior mountains no spectacular waterfalls have yet been discovered, the rivers descending to the undulating country in a series of rapids rather than by waterfalls. The largest river, the Rejang, has a length of 350 miles and is navigable for small coastal steamers as far as Kapit, 150 miles upriver. Kuching, the capital, is situated on the Sarawak River eighteen miles from the sea and can be reached by ships up to 2500 tons. Besides being the seat of government, Kuching is the administrative headquartera of the First Division. The town is growing rapidly and the population 1.S estimated at about fJJ 000 of whom the trading corrmunity is mainly Chinese, with large Malay end other smaller communi ties occupying suburban areas. The main part of the to~, with its wharves and warehouses, government offices, museum and other public buildings, schools and places of worship of the various cO!M\:r,itiea, and the main residential areas, is on the south side of the Sarawal( River. Access to the north side is mainly by small passenger ferry but vehicles may reach the northern residential areas across the river b,y a BU3pension bridge and a ml.nor road. On the north bank of the river directly opposite the contre of the town are situated the Governor IS residence, knotv'n locally as thG Astana and formerly the palace of the Rajahs of Sarawak, end Fort Hargherl ta, another link with old Sarawak. Behind these buildings are res:"dential a!'eas and on the river banks, upstream and down, are extensive Halay villages or ka.'Ilpongs. The business part of the town and the inner suburbs are adm!.nistered by a fully elected municipal council. Control of the outer suburbs and residential areas is in the hands of a Rural Di~trict Council. Sirr.c.'1ggung is cl tuated on the Lupar River and is the administrative heooq'larter3 of the Second Division. The population of this division consists mainly of Ibans or Sea Dyaks I with a few scattered settlements cf Nalays in the coastal areas and a small population of Chinese living in the towns. Navigation on the Lupar River is hampered b,y a tidal bore. Sibu is the second largest town in the terri tory and is expanding rapidly. It is situated about eighty miles from the sea at the head of the Rejang delta and can be reached b,y ships of up to 2500 tons. The population is estimated at about 30 000 and the town is the administrative headqua!'ters cf the Third Division. I t is lOW-lying and subject to flooding when t.he spring tides coincide with the arrival of floodwaters fro,n the Rejang c~tchment areas. The inhabi tants of the town are mainly Chinese~ with Malay and Melanau settlements adjoining the business areas. Sibu, with Sarikd a:"ld Binatang lower down the river, handles a large proporticn of the import and export trade of the country.
Page 3 Miriis the administrative headquarters of the Fourth Division and owes its existence to the openiIJg of the Sarawak oUfields in 1910. AJ.though oU is still produced, the neighbouring oUfields of Brunei bave beccme of far greater ilIIportance. The Miri river bas a shallow bar which prevents all but small coastal vessels from entering, and the shaJ.low coastal waters force larger ships to.anchor about three miles out to sea. LimbaIJg is situated on the Limbang River and is the administrative headquarters of the Fifth Division.
Binatang and Sa.rikei are the main towns of the Rejang River delta and are ilIIportant ports for overseas shipments of pepper, timber and other products of the Rejang River plains. The Tanjong Mani deep water anchorage further down the river can accommodate vessels of up to 10 000 tons. Of the other towns, BintuJ.u is the largest and developnent of this coastal town shouJ.d follow the openiIJg up of the hinterland for rubber growing. The characteristic features of the cl:lllla.te of Sarawak are heavy rainfall, a uniform temperature and high humidity. The mean annual rainfall at Kilching is 158 inches. This ccmpares with London's mean annual of 24 inches, New York's 42 inches, and Singapore's 95. It is not unusual for rainfall to exceed eight inches in a day at one place (especially during the north-east monsoon) whilst at another merely sixty mUes away no rain may occur during the same period. A large area of the country receives between 120 to 160 inches of rain. The highest recorded fall is at Long Akah on the Baram River, with a mean annual rainfall of 236 inches. The mean surface t~rature varies between 72~ and 88~ with the highest recorded maximum 97°F and the lowest minimum 68~. The relative humidity is generally high throughout the year.
From the beginning of October untU nearly the end of February, the north-east monsoon brings heavy ra.infall, particuJ.arly in the coastal belt. The monsoon moves at ~ fa.irly uniform speed a.cross the China Sea, but once south of latitude 5 N. its average speed decreases, and at times its boundary may become stationary or even malte a temporary retreat. The rain accempanyiIJg the boundary may then persist for several days and add substantially to the 'total rainfall. An exposed coastal belt like Sarawalt is therefore heavily influenced by this bo~ry layer at its southmost trends, giving a rainfall of twenty inches and more during, usually, November, December and January, whilst areas in Borneo, south of Sarawak . (except the north-west coast of Indonesian Borneo) are sheltered from this. Four seasons can be distinguished: the north-east monsoon, as bas been said - from October to January or Februaryj the mUd ~outh-ea.st monsoon, from April to July or August j and two shorter seasons of about. eight . weeks each, separating the end of one frem the beginning of the other.
Page
4 (
3.
THE CHOLERA <XJTBREAK - 1902
Detailed medical information on this is la.cking, but reports by Residents and people who were in Sarawak at the tJ.me indicate tha.t there was a high morta.lity rate in certain areas. Elders J..iving in the Second Division state that the outbreak reduced the popuJ..a.t1on of that Division by nearly ha.lf, but this is probably an exaggeration. Sane information on the outbreak is contained in monthly reports contained in the Sarawak Government Gazettes published during 1902 and these reports have been s'UIllD8I'ized for inclusion here. PreviOUS to the 1902 outbreak., there was a cholera epidemic in 1888, but apparently this was not nearly so severe. In 1902 during the la.ter part of May, ,;une and July, there was a severe drought throughout Sarawak, and particularly so in the southern ha.lf of the territory. Wells were nearly dry or completely so in sane areas. At this time an expedition bad been organized to punish groups of Dyaks living in the interior of Sima.ngga.ng District, who were attacking and killing friendly neighbours. A force of .sane 12 000 lQYal pyaks, including sane Ma.l.a.ys was assembled a.nd the expedition moved up the lupar River (Batang Iupar) to Sima.nggang in about 800 boats. On leaVing S:IlIIangga.ng, a.ll appeared well, but when the expedition proceeded sane d1.stance up the river, cholera broke out and spread rapidly.
Mention is made of existing insanitary conditions, and of the drought which bad not broken. There were over 1000 deaths in the force, which eventually had to retire without accomplishing its mission. The surviving sick and healthy members dispersed to their respective longhouses and viJ..1.e.ges. The outbreak occurred about loth June and la.sted untU 29th June. The report states that the Batang lJlpe.r was polluted with the corpses and shields of members of the expedition. Cases of cholera then appeared in several other areas, and were attributed to the dispersal of Dyaks after the break-up of the expeditionary force. Thus, in the First Division, Silllunjan, Gedong, Sabangan and Kucbing all bad outbreaks. KaJ.a.J.tB., Batong, Kabong and Pa.ku in the Second Division were also affected, the most serious outbreak occurring at Kal.a.ka. where there were many deaths. In the Third Division, Binatang, Sibu and Kanowit reported boats returning fran the' expedition full of sielt men, who were barely able to manage their craft. All these towns bad outbreaks, the first case in Sibu occurring in the ,:r;rison. Multah and Oya in the Third Division were also involved. In the Fourth Division cases were reported fran the Baram and Bintulu, but there it appears the outbreaks were small and the mortality low. In Kucbing the Principal Medical Officer sent in a brief report on II July 1902 concerning the situation in the town. This stated that the disease bad appeared in a sporadic form during the months of June and July. Apparently, the first cases in Kilching occurred about five weeks previous to bis report, and so it seems the first case occurred about 7 June 1902. The report states that the disease never assumed seriOUS proportions in Ki1ching town.
".....
Page 5 Reports for August indicate that cholera was dying out in many areas, and had alrea.cl;y disappeared frcm same. Reports for September state that the disease had disappeared entirely in all areas. Consideration of the above reveals the following interesting features: (1) The outbreak started a..lJ:nost simultaneously in the Batang Illpar area and in ICuching. Obviously, there was same common focus of infection, probably associated with travellers fram an infected kampong. The Fifth Division remained free of the disease. There was a period of severe drought commencing about two months before and-lasting throughout the outbreaks when most wells became dry. Enviromnenta.l sanitation generally was of a very poor standard. The outbreak appears to have been spread by infected travellers.
(2) (3)
(4) (5) (6) (7)
Morbidity and mortality rates were fairly high, the number of dead amounting to about 1500. The outbreak in Kuching was followed by cOllllllents on the need for :llnprovement of the water supply for the town.
4.
THE CHOLERA CXJTBREAK - 1961
On ~rednesda.y, 12 July, a health inspector fram the ICuching Rural District Council reported several deaths in Kampong Surabaya.. This kampong is one of a number lying across river, opposite Kucbing town. The Divisional Medical Officer was asked to investigate, and he reported the next morning that there were several cases of what appeared to be severe dysentery in the Kampong, one of whcm had been persuaded to enter the hospital. A full laboratory investigation was therefore made possible to help diagnose the disease.
A meeting was held in the Medical Headquarters in the afternoon of 13 July (second day of the outbre~) to discuss the situation and decide what public health measures were necessary to bring it under ~ontrol. In view of the fact that the infection was gastro-intestinal, the following decisions were taken: First Second to prOvide, if possible, a safe water supply for the people in the area and thereafter to prohibit the use of all wells. to send at once a team of spraymen to control any flybreeding in the area.
Page
6 (
Third
-
to deploy a team of Assistant HeaJ.th Visitors to visit every bouse, search for cases, and give early treatment.
The ptlbUc were aJ.so informed through the press and by repeated radio broadcasts regard.iIIg measures to' be adopted to improve environmentaJ. sanitation and prevent infection. Briefly the following advice was tendered: (1) Boil all drinking water.
(2)
Avoid eating food which is not cooked. Keep all food and drink covered. Wash all cooking and eating utensils thoroughly. Practise personaJ. clea.nliness and use latrines wherever possible. K1ll all flies.
(3) (4) (5) (6)
(7) ( 8)
Dispose of all refuse in a proper manner. Ensure the clea.nliness of the hane and its surroundings.
Mea.nwbile tbe nature of the outbreak was further considered. It could not be food poisoning in view of the scattered nature of the cases and the absence of any camnon food factor. It was probably a severe form of ~sentery, 1Mch was undoubtedly related to the unusua.lly long dry spell persisting at the t:ime, as a result of which the sba.llow wells in the kampongs were nearly dry and probably heavily contaminated. There seemed a poSSibility, in view of the clinicaJ. picture, that the disea.se was cholera, which might have entered the country by sane remote and unlucky chance. The results of the laborato~ tests, it was concluded, would provide the answer the following day. However, during the meeting information was received that vibrios had been identified in specimens taken fran the :patient admitted to the hospitaJ. on the previous day. The following day (third day of the outbreak) the news was transmitted to the public in Sarawak by radio and in newspapers, and Geneva was notified, via the WHO Epidem.iologicaJ. station in SiDga.pore, that the first Division of Sarawak had been declared an infected local area. Immediate action was taken as follows:
(1)
The Government Secretariat was requested to author1ze expenditure up to the amount necessary to control the outbreak. The Medical Department was given a ''blank cheque" immediately.
(2)
had been confirmed as cholera, and a request was made that careful attention be paid to the points referred to in the statement issued the previOUS day in ne'\\"Spapers and on the radio. These were repeated, and in addition it was announced that vaccination centres would soon be opened and mobile vaccination teams established. The co-operation of all was earnestly requested, and people were requested not to panic. The public were informed that the disease
II i
II
II
II II
Page 7 (3)
Appeals for immediate supplies of vaccine were sent to neighbouring countries by telegram, there being only 2500 doses of vaccine in the country on the day of the outbreak. The requirements for international travel were given wide
(4) (5)
publiCity. The people living in the affected kampongs were asked to restrict their movements, and to discourage visitors to the area for the time being. A scheme for the priority vaccination of the following groups was drawn up (a) (b) (c) (7)
(6)
Inhabitants of infected kampongs All contacts
International travellers
All contacts were asked to remain at home for a period of at least one week, and all employers of labour were asked, via the press and radiO, to co-operate by encouraging any known contacts to do so.
(8) (9) (10) (11)
Arrangements for the isolation and treatment of cases in the General Hospital, Kuching, were made. Supplies of equipment and drugs were checked and extra amounts ordered where necessary. Arrangements were completed for'the supply of safe drinking water by barge to the infected kampongs concerned. Emergency Public Health Regulations were prepared, approved, and published for the control of wells.
By Saturday, 15 July (fourth day of the outbreak), a total number of sixty-two suspected or bacteriologically proved cases of cholera had been reported. The following additional measures were put into effect the same day:
(1) (2) (3)
A daily distribution of safe drinking water to the affected kampongs using water barges. The broadcasting of advice and information to the blmpong people through a loudspeaker mounted on a launch. The compulsory vaccination of all travellers leaving the First
Division for destinations within and outside Sarawak. For this purpose two vaccination centres were set up, one at Kuching airport and. the other at Kuching wharf, and enabling public health legislation was approved and published during the day. (4) Other public health legislation concerning powers of disinfection and destruction of ~contaminated clothing and domestiC articles were also approved and published during the day.
Page 8 (5) Preparations were made to open seven other vaccination centres for the public in Kuching. Those living in the better residential. areas with a safe drinking water supply, were requested to refrain fram rushing for vaccination as priority was being given to contacts and to those most at risk. A special announcement incorporating the above was prepared to let the public know what further measures had been taken. The Information Department was requested to give the announcement the widest possible publicity in all languages and to repeat it the day following. In a further announcement the public were informed that group vaccinations would not be carried out in schools l institutions, factories l etc. in order to uphold the principle of protecting those at risk first. For general information it was explained that one injection would be given which would became effective after five or six days.
(6)
(7)
There was a generous response to an appeal made earlier for volunteers to man the vaccination centres. Nineteen volunteers with previous experience in vaccination techniques were selected and reported for duty on Monday, 17 July 1961 (sixth day of the outbreak). In addition, assistant health visitors were withdrawn from the Tuberculosis Control Project and attached to vaccination centres. A few retired medical staff were also temporarily re-employed with an offer of remuneration for their services, and local authorities co-operated by offering the services of their health inspectors. Assistance was received from the Sarawak Constabulary in maintaining .control of the large crowds attending the centres for vaccination. Investigation teams were set up to follow-up all reports of suspected cases, and institute measures to improve environmental sanitation by health education. The isolation and vaccination of contacts were carried out in appropriate cases. Each investigation team was led by a fully qualified health inspector or health sister, and was accompanied by spraymen on loan from the Sarawak Malaria Eradication Project detailed to treat all potential fly breeding areas with B.H.C. (Gwoomexane). Mention has been made already of the arrangements completed to provide free of charge a supply of safe drinking water to all people living across river from Kuching. The Public Works Department and Marine Department worked out the details, and provided two barges. On these the Public Works Department mounted water tanks and pumps and they were then towed and anchored as required at strategic points on the river opposite the affected kampongs. In addition, the water barge "Ba.dak" was used for a period of four days. The barges fitted with tanks ~ pumps were towed to their stations by the launch "Doreen". At first there was no restriction placed on the amount of safe drinking water taken away. later a system of rationing was contemplated but considered unnecessary in view of the relatively small quantities of water carried away in containers by the kampong people.
Page 9 In the General Hospital, Kuching, separate wards were made ready for the reception of cases, and a call for nursing volunteers produced a good response. Members of the Sarawak Branch of the British Red Cross SOCiety offered their services in the nursing of the sick in hospital. Additional emergency supplies of Sulphadimidine, Glucose-saline, and Hartmann's solution (in disposable polythene packs), syringes, needles and enamelware were obtained locally. At this stage it was decided that patients in outstations should not be brought into hospital, but that temporary field hospitals should be established as and when necessary. This decision was taken in view of a report received on 15 July (fourth day of the outbreak) that the disease had appeared in Lundu, which was about eight hours by launch from Kuching in favourable weather, but virtually unapproachable during rough weather.
U:P to 18 July (seventh day of the outbreak), the morbidity and mortality position was as follows: First Division Jl
116 cases, including 22 deaths 1 case (imported fram Kampong Suraba.ya, Kuching, and isolated immediately)
Third Division, Sibu District
The total number of vaccinations carried out in the First Division amounted to 7837. Meanwhile the Divisional Medical Officer, First Division was despatched to deal with the reported outbreak at Lundu. In this he was assisted by the WHO Senior Malaria Adviser (who volunteered his services), and a team of vaccinators , health staff, and sprayers. Sufficient equipnent was taken to establish a field hospital in the government dispensary at Lundu. On 19 July 1961, (eighth day of outbreak) it was found that supplies of vaccines were running short, and it was not known for certain when further supplies from various sources abroad might arrive. It ,~s therefore decided to introduce for all but small children the intradermal. method of vaccination, thus Using only one-third of the dose required for the subcutaneous route. Fortunately, most of the vaccinators and all the assistant health visitors from the tuberculosis control project were familiar with the technique. For those unacquainted with the method special tllition was arranged.
Information was received the same day (19 July) that the disease had made its appearance in the Second Division at two k8.lllJ?ongs on the coast named Beladin and Maludam. A death had occurred in each of a person previously complaining of all the symptoms of cholera, and recently returned from Kuching. The measures adopted in the First Division, which have been described already, were applied to the Second Division. The Divisional Medical Officer was provided with additional staff for investigation, vaccination and treatment together with the necessary supplies of equipnent, and drugs and such vaccine as could at the time be spared.
Page 10 (
In the meantime, the wells in the infected kamPODgs near Kuching which bad previously been closed, were checked by the Chemist Bacteriologist of the Public Works Department. His report showed that, with one exception, all the samples examined by him were polluted with faecal matter. Disinfection with chloride of lime was consequently carried out. Fresh water by barge was now being supplied at the rate of approximately fifty tons daily. By the week ending Saturday, 22 July (eleventh day of the outbreak) the situation in the country was as follows:
First Division (declared infected local area) Second Division (under investigation) Third Division
192 cases, including 32 deaths
2 cases, including 2 deaths (imported) 1 case (imported)
The total number of vaccinations carried out in all divisions amounted to 67 820 of which 65 "694 were given in the First Division. Most of the population of KUching and Lundu were now protected by vaccination aga.inst cholera, and it was decided to extend the vaccination campaign by the formation of mobile teams which would operate by road and river in the rural areas of the First Division. All but two of the centres in KUcbing town were closed to release vaccinators for the mobile teams. At the same t:1me it was considered advisable to extend vaccination in the Second Division though the position there was still under investigation and no further cases bad been reported. All these :measures were given wide publiCity, and daily broadcasts were made in advance of the itineraries of mobile teams. During the week cc:mnencing Sunday, 23 July (twelfth day of the outbreak) there were many reports of cases in various J,l6Xts of the First and Second Divisions, all of which were followed up and investigated. A severe outbreak was confirmed at Gedong in the First Division and a field hospital was consequently established there. Isolated cases occurred in various other areas of the First Division, and were dealt with by treatment on the spot if symptoms were mild, or transfer to hospital, if severe. Further cases were discovered at Maludam, Debak and Ensurai in the Second Division which was accordingly declared a locally infected area. By the weekending 29 July (eighteenth day of the outbreak) the position was as follows : First Division Second Division (Various kampongs) Third Division
215 cases, including 44 deaths 32 cases, including 15 deaths 1 case (imported)
.. Page 11
The total number of vaccinations in all divisions aJllounted to 133 753 which included 106972 given in the First Division and 23 431 in the Second Division. By the week ending 12 August (thirty' JsecoDd day of the outbreak). the position had shown little change and was as follows:
First DiVision SecoDd Division Third DiVision
219 cases, including 44 deaths 32 cases, including 15 deaths 1 case (imported)
The total number of vaccinations in all divisiOns now stood at 205 687 of which 164 358 were given in the First DiVision and 36 009 in the SecoDd Division.
•
In view of the fact that no cases bad occurred in the Second. Division for sixteen days, it was declared free of cholera on 14 August 1961, and it was hoped soon thereafter to be able to declare the First Division free also. However, September proved to be a disappointing month in this connection. On 1 September (fifty-aecond day of the outbreak) one more case was reported fran the Second Division, which was accordingly re~clared an infected local area. On the following day one case was reported in the First Division, followed by two more on 7 September. Then on 8 and 9 September came reports of scattered outbreaks in the Third Division. It was evident that the outbreaks in this division were not just isolated cases possibly imported fran the First Division. It was therefore declared a locally infected area, all the measures already described were put into operation there, and a mass vaccination campaign was carried out. By the week ending 16 September 1961 (sixty-seventh day of the outbreak) there had been only two further cases in the First Division, none in the Second Division, but there was now a total of sixteen cases with four deaths reported fran the Third Division at various kampongs, below Sibu, on the ReJang River. These were from near Sibu town, raro, B1natang and Sarikei. Vaccinations carried out in the Third Division amounted to 68 207. As in the case of the· Second Division, personnel, equipnent:kl.nd supplies were sent to the Divisional Medical Officer from Kuching. Mobile vaccination teaJllS were used extensively in this DiviSion, as in other diVisions, aDd on 18 September there were twenty-two such teams operating in the lower Rejang area. Before the close of the month cases had been reported in Matu and Balingian and the population in these areas bad been protected by vaccination. By the week ending 30 September (eighty-first day of the outbreak) the epidemic bad spread to the Fourth Division and the position was as followe :
First Division
226 cases, including 45 deaths
... Page 12
Second Division Third Division Fourth Division
33 cases, including 15 deaths 40 cases, including 9 deaths 1 case; no death
The case in the Fourth Division was discovered on 29 September (eightieth day of the outbreak) at Niah, and the division was declared infected with cholera. The total number of vaccinations carried out in all divisions was 36.1 181 which included 167 E98 in the First Division, 56 (fJ7 in the Second and 131 8)5 in the Third Division.
Onl¥ one further case occurred in the country. This was discovered on 5 October (eighty-sixth day of the outbreak) in the Third Division. On 12 October (ninety-third day of the outbreak) the First, Second and Fourth Divisions were declared free of cholera, and by 19 October (lOOth day of the outbreak) this was extended to the whole of Sarawak. The fiDal total of cases for the country was 301 of whan 70 died. The total number of vaccinations carried. out in all divisions was 444 ~8 which constitutes 6fJI, of the entire population of the country, or 741> of the popul.a.tion living in areas considered to be at risk, i.e., excluding the five districts of Kanowit, Kapit, Baram, Limbang and tawas. In concluding this section on the cholera outbreak of 1961, it must be pointed out that the present figures for morbidity and mortality differ fran those submitted during the outbreak. The differences have arisen as a result of a caref'ul perusal of the final returns received fran all divisions. Thus one case recorded as occurring in the First Division is now included in the figures for the Second Division, because the patient only came to Kuching fran his heme in the Second Division for the purpose of treatment. The Second Division figures now include cases and deaths which were reported at the time but not accepted as cholera. Areview of these indicates that they were all probably suffering fran the disease. In the case of the Third Division, there was a misunderstanding at the time of repM1;ing, and deaths were shown separately fran case" who recovered. This was not appreCiated at Medical Headquarters, where the total number of cases was taken to include deaths fran the disease. The error is therefore corrected now.
The final returns for Sarawak on 19 October (lOOth day of outbreak) therefore read:
First Division Second Division Third Division
22~ cases, including 45 deaths
33 cases, including 15 deaths 41 cases, including 10 deaths
Fourth Division FUth Division Total
-.
1 case, no death no cases 301 cases, including 70 deaths
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WORLD HEALTH ORGAN I ZATION
ORGANISATION MONDIALE DE LA SANTiIl
,. REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAL DU PACIFIQUE OCCIDENTAL
18 April 1962
Manila, Philippines 16-19 April 1962
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"EL TOR" CHOLERA
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THAIIAND
WPR/212/62
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--. "EL TOR" CHOL1!;£t!l. IN TH1IILl.ND
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The so-called classical cholera outbreak started in Thailand on 23 May 1958 and subsided in October 1959. The seven last cases (six from Bangkok and one from another province) were noted on 6 October 1959. In the middle of 1960 "El Tor" 'vibrios were found in Bangkok by Mukerjee. This organism, however, was only seldom cultured from few diarrhoeic patients, from food and from water samples, until in September 1960 the first epidemic of "El'lor" paracholera started in Ubol Province, NorthEast Thailand, in which a total of 700 cases were noted. In that month the Ubol Hospital (400 beds with twelve doctors) admitted fifty-seTen patients. There were more cases: in October, 157, and in November, 400. During the last month the co-operation of the SEATO Oholera Research Laboratory, the Royal Thai Army Nedical Division and the Thai Department of Public Health were asked to investigate the disease. The "El Tor" organism was found as the causative agent and the diseale was mild with no mort ali ty and rapid recovery. No case has been found since 6 December 1960 • lrJe believe that our "El Tor" organisD' might be a different strain from those found in other countries of Asia. However, we would like to mention that about 80% of the people of Ubol were previously inoculated with classical cholera vaccine, and at that time (September - December 1960), we 1coculatect with that vaccine again mos t of the people in Ubo1. From the epidemiological point view, Ubol has a population of 1 100 000 living scattered over a large area and only 25 000 persons staying in the town of Ubol. rbol is situated about 500 km east of Bangkok. Ylost of the people are farmers, and there are some admixtures of Ohinese and Laotians. The income of each individual is low, about USi75 per year in average, but the cost of living is very low. A family can live on about US.>12 a month. They have the habit of eating raw fish which is caught in the local rivers and canals, havlOg acquired this custom from Laos. The water supply is obtained from chlorinated tap water originating from a large river passing through the town, but because the price of tap water is high, only \'/ell-toeodo people and government officials can afford to use it. Thus many people use water from open, deep wells. Food is sold in open-air markets. There are many flies, especially during the hot season. Fortunately, during the time mentioned above, it was the cold season and not many people required too much water. Also, flies were scarce.
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• WORLD HEALTH ORGANIZATION ORGANISATION MONDJALE DE LA SANT~
REGIONAL OFFICE FOR THE WESTERN PACIFIC BUREAU R~GIONAL OU PACIFIQUE OCCIDENTAL
MEETING FOR THE EXCHANGE OF m'ORMATION ON EL TOR VIBRIO PARACHOLERA Manila, PbUippines 16 - 19 April 1962
13 AprU 1962
REFERmCE ON PARACBOLERA 1. GENERAL
DE, S.N.
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Cholera, its pathology and pathogenesis. and Boyd, 1961. 141p •
Eklinbergh, Oliver
FElSERFELD, O. The pathogenicity of El Tor and Nag vibrios. Proceedings of the Symposia on Cholera held during the Diamond JubUee of the Baffkine Institute, Bcmbay, January 10th to 14th, 1959. (photocopy). PHITJ:tpS, R.A. The patho-pb;ysiology of cholera. WHO Scientific Group on Cholera Research, Information Document No. 12, 28 March 1962. lOp. (mimeographed).
POLLI'l'ZER, R. Review of the recent literature on cholera. 25, 23 May 1959. 59p. (mimeographed).
Document wao/Cbolera/
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POLLITZER, R. A second review of the recent cbo1era literature. Document WHo/Cho1era/26, 31 March 1960. 36p. (mimeographed). SAYAMOV, R.M • The El Tor Vibrio. WHO Scientific Group on Cbolera Research, Information Document No.8. (translated fran Russian). 2lp. (Mimeographed) •
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2.
EPIDEMIOLOGY AMGON, P. and FAMATIGA, E.G.
El Tor vibriO in the recent outbreak of cholera. (PbUipp1nes) • Part I. Isolation and Identification. Part II. Serological Reaction of the Cases. Part In. The El Tor Vibrio in Food and Water. 26p. (Typewritten) •
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FEISENFELD, O. El Tor vibrios of the Ogawa subtype occurring in an epidemic of diarrheea with vomiting in Ubol, Thailand. J. Trop. Med. Byg., 1961, Vol. 81-, 8, 207-211. (photocopy).
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GAR, K.H. et ala First cases of paracholera El Tor (Enteritis Cboleriformis El Tor van Wghem) in Java. Trop. Be Geog. Med. 1958, Vol. 10, 113-116. (photocopy). HENDERSON, D.A. Cholera El Tor - Philippine Islands - Inter:lm Report, March 19, 1962. 22p. (mimeographed).
HONG KONG, Government of Report on the outbreak of cholera in Hong Kong covering the period lith August to 12th October 1961. A white paper laid before the Legislative Council, 13th December 1961. 48p. (Mimeographed). KAMAL, A.M. Endemicity and epidemicity of cholera. WHO Scientific Group on Cholera Research, Information Document No. 14, 29 March 1962. 14p. (mimeographed).
MOOR, C.E. de Paracholera (El Tor) Enteritis Choleriformis El Tor van Loghem. D.lll.. Wld. Blth. Org. 1949, 2,5-17 (reprint).
MUKERJEE, S. Bacteriophage susceptibility test in differentiating vibrio Cholere.e and vil1rio El Tor. WHO SCientific Group 'on Cholera Research, Information Document No. 10, 27 March 1962. 1p. (Mimeographed) • MUKERJEE, S. Bacteriophage typing of cholera. WHO Scientific Group on Cholera Research. Information Document No. il, 27 March 1962. l2p. (m:lmeographed) • MUKERJEE, S. Problems of Paracholera El Tor. WHO Scientific Group on Cholera Research. Information Document No.3, 16 February 1962. 8p. (Mimeogra.phed) •
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POLLITZER, R. Cholera studies. 10. Epidemiology. 16, 783-857. (reprint). WHO.
Bull. Wld Blth Org. 1951,
International Quarantine Conmittee Paracholera due to the El Tor Vibrio. Document WHO/IQ/l20, 2 November 1961.
New Epidemiological lata. 4p. (m:lmeographed).
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International. Q;ua.ra.ntine Unit. Cholera epidemics in the world during tbe last few years (1955-1961). WHO Scientific Group on Cholera Researcb, Information Document No. 15, 1 April 1962. 7p. (mimeographed). Notes on paracbo1era in Sulawesi (Celebes). Hyg. 1959, 8, 1, 72-78. (journal). Am. J. Trop. Med.
TAHAMAL, S.T.W.
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DIAGNOSIS BJRRCMS, W. am POLLITZER, R. laboratory diagnosis of cholera. 275-2)0. (re}ll'int).
Bull. Wld Hlth Org. 1958, 18,
llJ'l'TA, N.K. and PANSE, M.V. An experimental st~ on the usefulness of bacteriophage in the propbyle.xix and treatment of cbolera. WHO Scientific Group on Cholera Research. Information Document No.6, 15 March 1962. 9p. (mimeographed). FELSENFELD, O. Scme observations on cholera (El Tor) epidemic in 1961. WHO Scientific Group on Cholera Researcb, Information Document No. 13, 27 Marcb 1962. 16p. (mimeographed).
GALWT, J. Recherches sur les antigenes thermostables de Vibrio Cho1era.e. Localisationetis01ement de l'agglutinogene 0 specifique. CMS Groupe Scientifique des Recherches sur Ie Cho1era, Document d'information No.1, 16 fevrier 1962. 6p. (mimeographed). GALWT, J. and. NICOLLE, P. Research on the ~sogeny and Pbage typing of Vibrio Cholerae and. Vibrio El Tor of various geograpbical origins. WHO Scientific Group on Cbo1eraResearch, Information Document No.2, 16 February 1962. 1p. (mimeographed). LAHIRI, D.C. Bio1ogica1 ass~ of cholera. vaccine. WHO Scientific Group on Cholera Research, Information Document No.7, 16 March 1962. 21'. (mimeographed). MONSUR, I:.A. Bacteriological diagnosis of cholera. under field conditions. WHO Scientific Group on Cholera Research, Information Document No.5, 5p. (mimeographed).
MUKERJEE, S. and GUBA ROY, U.K. Evaluation of tests for differentiating Vibrio Cholerae and El Tor Vibrios. AIm. Bioch. &. Exp. Med. 1961., XXI, 5. 12) -.1.32 (photocopy).
POLLITZER, R. Cholera Studies: 1. Practica1 laboratory d.iaenosis. Hlth Org. 1956, 14, 705-193. (reprint). :EkJll. Wld
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INDONESIA, REPUBLIC OF, Depa.rtment of Health Manual for the recognition, treatment and prevention of cholera. Djakarta" De:pe.rtment of Health R. I., September 196.1. 1P. (Mimeographed) • LAKSANAPlIJK" P. and KEOPIDNG, M. Clinical study and treatment of Asiatic cholera in 19'}). Am. J. Trop. Med. Hyg. 1960, 9, 620-625. (photocopy).
MORGAN, F.M. et ale Treatment of cholera (and ''EJ. Tor"). Reprinted with permission fran the Journal of the Medical Association ot 'l'be.iland, 1959, 42, 5, 413.422, by Abbott Laboratories, Philippines.
POLLITZER, R. Cholera studies: 9. Symptanatology, diagnosis, prognosis and treatment. Bull. Wld Blth Org. 1957, 16, 2}5.430. (reprint). SAYJW:)V, R.M. Prophylaxis and treatment of Cholera with bacteriophage. WHO Scientific Group on Cholera Research. Information Document No.9. (Transla.tion fran Russian). 12p. (mimeographed). "'I
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PREYmmON AND CONTROL
DELPY, L. Report on the possibilities of improving cholera vaccines and . methods of evaluating their effectiveness. WHO Scientific Group on Cholera. Research. Information Document No.4, 28 February 1962. 22p. (mimeographed).
POLLITZER, R. Cholera Studies: 11.
Prevention and Control. Org. 1957, 17, 67-162. (reprint).
Bull. W1d lUth
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