WPRO 0155
ElGLISHONLY
SECOND SYMPOSIUM ON BeG VACCINE PRODUCTION IN THE SOt1rH-EAST ASIA AND WESTERN PACIFIC RIDIONS
Sponsored by the WORLD HEAILrH ORGANIZATION RIDIONAL OFFICE FOR THE liESTERN PACIFIC
Manila, Philippines 22-26 September 1969
FINAL REPORI'
,
World Health Organization Western Pacific Regional Office Manila., Philippines Februar,r 1970
WPR/051/70
TABLE OF CONrENrS
1.
INTRODUCTION •••••••••••••••••••.•••••••.•••••.••. SUMMARY OF PAPERS PRESENTED AND DISCUSSIONS
1
2. '. >
2 2
2.1 Adoption of seed-lot system •••••••••••••••• 2.2 Preparation of liquid vaccine ••••••••••••••• 2.3 Freeze-dr,ying ••••••••••••••••••••••••••••••• 2.4 Quality control ••••••••••••••••••••••••••••• 2.5 In-vivo studies of BOG strain ••••••••••••••• 2.6 Choice of BCGstra1n and doses •••••••••••••• 2·7 Other mtters .................................... .. RECOMMENDATIONS
4 5 10
7
....................................................................
17
ANNEXES: 1 2
LIST OF PARTICIPAllTS, CONSUIIl'ANrS AND SEXJREl'ARIAT Al'ID S~RmARIAT .......................................................... 19 LIST OF WORKII'G PAPERS
............................................
21
3
EVALUATION SUMMARy ••••••••••••••••••••••••••
23
, •
1. IN'l'RODOCTION
In November 1959 the first symposium on BOG vaccine production was held in Manila. Seven countries in the South.-East Asia and Western Pacific Regions At the end of the symposium the participants unanimously
sent participants.
agreed that it had been mst profitable and fruitful and they proposed that similar meetings should be organized in the future. The Second Symposium on BOG Vaccine Production, sponsored by the WHO Regional Office for the Hestern PaCifiC, took place from 22 to 26 SepteJ!lber
1969.
Nine countries in the
South-East Asia and Western Pacific Regions
sent participants. A list of the participants, consultants and staff is given in Annex 1. The sympoSium was opened officially on the morning of 22 September by Dr Francisco J. Dy, Regionsl Director, Regions.l Office for the Western Pacific. Dr Dy pointed out that the main purpose of the symposium was to achieve better liaison and greater uniformity among the BOG production laboratories in the two regions. He expressed the hope that the free exchange of information
and discussions would bring better understanding of the problems concerning production and ensure the mre effective use of the vaccine in national tuberculosis control programmes. BOG vaccination would reUllin, at least for
the coming decade, the 'most important control measure for tuberculosis in the majority of the Cleve loping countries. The Ullin task of the participants was
to discuss the DCG strain, dosage and the standardization of procedures so that uniform batches of highly potent vaccine could be prepared not only within one and the same laboratory but also in different laboratories. The partiCipants elected the following partiCipants to conduct the
working sessions of the meeting:
- 2 -
Chairnan Vice-Chairman Rapporteurs
:
Dr J.S. SUlI1p8.ico Dr T. Sawada Mr V.F. Davey Dr J .S. Suri
The topics for discussion were as follows: 1. 2.
Adoption of seed-lot system Preparation of liCluid vaccine Freeze-drying Quality control In-vivo studies of BCG strain Choice of BCG strain and doses Other matters 2. SUMMARY OF PAPERS PRESEN:rED AND DISCUSSIONS
3.
4. 5. 6.
7.
2.1 Adoption of seed-lot system The subject was introduced by the Chairman who pointed out tha.t the
investigation and adoption of a "seed_lot system" (single strain with a uniform method of maintenance) was a matter on which a strong recommend.e.tion had been made during the first symposium in Manila in November 1959. Since
then, the seed-lot system had been defined by the vlHO Expert Committee on Biological Standardizstion* as the maintenance of a BCG strain in dried form (primary seed-lot), from which harvests for vaccine production shall be no more than twelve passages removed. with the seed-lot system. A paper l
•
was presented on the experiences
The data showed that the yield of cultures, the
number of culturable particles in the vaccine or the post-vaccination reactions (tuberculin reactions, skin lesions) in children had not been adversely affected by the adoption of the seed-lot system. The discussion brought
'liWid Hlth Org. teclln. Rep. Ser., 1966, 329.
-3-
useful. comments from several of the participants in regard to the expression of the yield of bacillary mss on a dry or wet weight basis. It was agreed
tba.t a seed.-lot system was lOOst desirable to guard against the risk of culture variation. 'Wall
The advantage of using a seed.-lot to ensure tba.t the vaccine was sate
described in detail and the participants agreed to follow the WHO
Requirements for Dried BOG Vaccine (see items 1.4 and 3.1 of the report already cited). A detailed description of the technique used for the maintenance and propagation of seed cultures was presented by each of the participants. A
seed.-lot system conforming in principle to tba.t specified in the Report of the WHO Expert Committee on Biological Standardization was used in all countries except three: in one, the number of passages exceeded twelve, in another, serial propagation and in a third, the production The discussion
owing to a limited supply of seed ampoulesj from culture to culture was still practisedj
of dried vaccine was still in the process of development.
of these procedures focused attention upon the virtues of confirming transfers to synthetic rather tba.n natural media. The majority of the laboratories
utilized transfers from the dried seed.-lot material (in lOOst cases the French strain ll73) to Sauton potato medium and the vaccine was prepared from theS'econd passageons8.uton 'liqUid medium. The cultures were
maintained on a limited nUmber of seriBl transferS' either on Sauton potato or bile potato medium. One laboratory reported tba.t the different strains used for production in this region did not differ to a degree which would affect the production of vaccine when grown on Sauton potato or liquid Sauton medium. It was
empba.sized during the discussion that sufficient ampoules of a primry seed-lot are available from the distributing centres to meet the requests of any production laboratory seeking to conform to the WHO Requirements for Dried BOG Vaccine.
- 4_
2.2 Preparation of liquid vaccine A paper2 was presented describing the use of Tween 80 in the production of BOG vaccine. The author stated that Tween 80 in a concentration of 0.005%
in the final vaccine concentration improved the tuberculin conversion rate eight weeks later and also one year after vaccination. The number of
culturable particles was higher when compared with vaccine produced without Tween 80. A similar observation has not been I1Bde in other countries. One
participant reported that vaccine without Tween 80 I1Bintained a higher number of culturable particles, Another found that the concentration of A third reported that his laboratory
0.005% Tween 80 was unnecessarily high.
used a concentration of 0.002% Tween 80 and stainless steel balls different sizes for milling.
of two
As a result of the discussion it was agreed
tha.t the inclusion of Tween 80 had to be considered along with the technique of grinding the BOO culture. It was also suggested that further field work
should be carried out to assess the influence, if any, of Tween Bo on BCG-induced tuberculin sensitivity in hUIlBD beings. The next three papers 3,4,5 described the effects of heat and light
upon liquid BCG vaccine.
The results
confi~d
the susceptibility of the
vaccine to the adverse effects of storage, ambient or high temperatures, and exposure to direct sunlight, diffused daylight or intense artificial radiation (ultra-violet or infra-red). It was agreed that precautions
against such exposure must be taken in both the production laboratory and the field. The next parar6 dealt with the growth pha.se of BOO strains.
A sUIllllary
was presented on the data obtained from the three experiments performed on a number of BeG strains, fifteen years ago, ten years ago and recently. The phase of growth, pH change in the culture and techniques of grinding the bacterial I1BSS were discussed for their relevance to post-dryj.ng survival.
I I I - 5 -
The results showed that the Ja];l8nese strain had given a liquid and dried
vaccine vith a viability superior to that of the French and Danish strains. It was pointed out that the present production technique differs from that used in the two earlier experiments-, although not to an extent likely to change the conclusion that was draWD by the author. A lively d1scussion
on the viability of vaccine after storage and the expiry date for liquid vaCCine followed. A paper7 on the influence of hooogenization procedures
on viability showed that higher speeds of milling, or prolongation of milling of the bacterial 178SS,
were detrimental to the quality of vaccine judged by
the number of culturab1e ];l8rticles, germination rate and measurement of o~gen
uptake.
The first of these tests was considered the least accurate
estiuate of the vaccine's viability. One of the participants called attention to the compromise which ImlSt be effected between the reduction of clumps in the vaccine and the preservation of viability in the vaccine. Another partiCipant reported that milling vith plastic-coated steel balls (7-8 mm in d1ameter) caused less reduction in viability than the uncoated steel. balls. One of the ];l8rticipants recommended to those who might be changing trom liquid to freeze-dried vaccine production that there were certain advantages in adopting for both stock Buspensions a cOIJlllX)n suspending fl.uid such as l. 'J'p sodium glutallllte. 2.3 Freeze-drying A paper on resistance to freeze-drying and heat stability after freeze-drying of eigbt BCG strains was presented. 8 The results showed
clearly that the Japanese strain 172 had the best survival rate and the greatest heat stability whether assessed on the basis of number of culturable particles, germination rate, or ~gen
uptake.
In six of the
- 6 -
BCG strains examined the younger cultures seemed to be more resistant to freeze-drying. Later investigations performed in the same laboratory after the development of a more useful freeze-drying technique, especially for the Danish strain 1331 and the French strain 1173, were reported by one of the participants. The beat stability of the above-mentioned strains was higher The oxygen uptake or germination
than that recorded in the paper presented.
rate gave a better assessment of survival than the number of culturable particles. A report9 on the drying and preservation of BeG vaCCine, when vaccine containing 80 mg
BCG per ml in 51> sodium glutamte was used, showed that
the prolongation of the heating stages of the freeze-drying cycle necessary to achieve low moisture content caused excessive inactivation of the viable particles. It was pointed out that the range or moisture content of the
concentrated vaccine could be wider than that of vaccine intended for intradermal use, preferably from 1 to f:J1,JI for the optilml post-drying viability. The paperlO on the stability of freeze. dried BOG vaccine under field conditions indicates, although the investigation is still incomplete, that even wlEn a vaccine prepe.red from strain 1331 has lost up to 7C1fo of culturable particles, it still gives acceptable post-vaCCination tuberculin reactions ten to twelve weeks after vaccination when measured by the Mantoux test
(5 T.U. RT22).
It was suggested that the survival rate after freeze-drying
with a somewhat lower viable count than that adopted as a minimum for field use could be successfully employed when distribution problems were serious. A paper11 on experimental stUdies on conditions for the manufacture of freeze_dried BeG vaccine in Korea was presented. The equipment used
to prepare a sufficiently viable product of acceptable stability was described.
- 72.4 Quality control Using 8S 8
reference the report of the Study Group on Requirements for
Biological Substences* each of the participants described the method used for sterility testing of BeG vaccine. The present practices show that some
laboratories are obliged to perform. the sterility test in the production area, a few use only one medium, some only one temperature of incubation, and in some the incubation period is too short. It was recommended that efforts should be continued to obtain better control of the laboratory environment, both in the production and testing areas, particular emphasis being placed on the former. air flow benches was mentioned in this connection. The use of laminar
Antiseptic spraying,
ultra-viOlet light and the protection of personnel were considered. The WHO Requirements for Dried BeG Vaccine, Part A, item 5, were discussed in detail. The identity test (5.1) is in use in all laboratories.
The purpose of the test for determining the absence of virulent lIWcobacter1a (5.3.1) was outlined. Two
A considerable variation was found between laboratories.
laboratories kept the guinea pigs under observation for six months aoo.
the number of animals used in different laboratOries varied from two to six. It was· considered that the importance of the test as a means of ensuing
protection of the persons to be vaccinated bad d1m1nishedwith the introduction of the requirements for a primary seed-lot system. However, the test is
still important as a means of protecting the IMnu:facturing establishment, in case severe complications are reported, and for the purpose it my be more practical to follow the WHO Requirements: a period of six weeks. A long discussion on the value of the test of skin reaotivity in guinea pigs (5.3.2) developed. One of the participants referred to the six animals observed tor
*Wid Helth. Org., tech. Rep. Ser., 1960,
~.
- 8 ..
difficulties encountered in expressing the results of this test in the most meaningful nanner: by Dr Guld. A method of evaluation of the results was then explained
Most of the pa.rticipants felt that it was now little more than The
a potency test and one reconnnended its deletion from the requirements.
consensus was in favour of retaining it as an optional test, more emphasis being put on carrying out the test in children, although it was not considered necessary to do sO with every batch of vaccine produced. One of the
participants considered that this would be difficult in view of the fact that direct BCG vaccination was now practised and there would be no data on the pre-vaccination tuberculin test. I t was suggested that a pre-
vaccination tuberculin test should be given when an assessment was planned. It was agreed that the requirements for the test should be left to the discretion of the national control authority. Only a few of the laboratories represented perform a test for total
bacterial content (5.4) on the final vaccine.
Some reported that the
necessary naterial for the determination of dry weight, as described in WHO!TB!Tech.Guide!67.6, was not available. be done. The opacity test could, however,
With reference to WHO!TB!Tech.Guide!67.6 the factors tnfluencing This test is useful for the' producer as
the opacity test was described.
an indication of tlE correct dose and the uniformity of the lots, but it was pointed out that the nationa.l authorities should determine the vaccine dose to be used and examine the consistency of the vaccine dose for each vaccine lot. Each of the partiCipants described how they carried out the test for number of culturable particles (5.5). Procedures were reasonably uniform Two of the
as regards the choice of medium and area of medium inoculated.
laboratories used dilUent conta.ining Tween 80 for the preparation of the dilution series. Greater variation was seen in the degree of dilution and
II
number of colonies counted.
- 9-
The design given in WB.O/'1!B/rrech.Guide/67.6 was discussed.
The
advantage to be gained from count1ngs obtained from two-fold rather ths.o ten-fold dilutions was illustrated. One of the participants mentioned the
mdified procedure used in his laboratory which permits an extension of the WHO statistical treatment of the results. Another presented the test plan
which was employed in his laboratory indicating the criteria of the minimum number of culturable particles in the batches to ps.ss the test. There was general agreement on the application of the stability test (5.6) for freeze-dried vaccines, but some debate upon its application in the selection of storage temperature and expiry dates. Two
of the producers
of freeze-dried vaccine felt that there were some contradictions between the wording of 5.6 and that of 10.2 (expiry date) in which a period of
twelve mnths is fixed as the maximum life of the vaccine at any one time. The desirability of some formal amendment to 10.2 to accommodate vaccines which merit an expiry period longer than twelve months was mentioned. difficulties were encountered in connexion with the rell¥lining items of Part A of the Requirements. In discussing the recommendation in Part B, 1.1, it was agreed ths.t the isoniazid-resistant strain is a new one and if it is to be used it must be validated as a new seed-lot. In the discussion of Part B, 1.2, it was pointed out that in countries where tuberculosis is a. major problem an acceptable level of untoward reactions can be considered as 1'/0 suppurative lymphadenitis in newborn, and skin lesions with a mean less than 7 mm in diameter in older children. In considering Part B, 3, on the efficacy and safety of the vaccine in !lBO,
No
it was felt that data from field tests should be sought regularly.
It was recognized that when ao initial tuberculin test is omitted in the vaccination programme the assessment of BCG-induced allergy will be very
- 10 -
dif'ficul.t.
It was also pointed out that the variations in the size of the
vaccination lesion could be useful in assessing the field performance of vaccine from anyone strain, while less importance should be attached to the tuberculin reactions. None of the participants are engaged in the prepare.tion of vaccine for oral use. 2.5 Percutaneous vaccination is only performed in Japan.
In-vivo studies of BeG strain A paper12 was presented on studies of tuberculin sensitivity and
vaccinal lesions among children vaccinated with twelve BOG strains.
The
vaccines were all prepared in one laborator,y and compared by vaccinating groups of children in India and Demmrk. The data indicated that there
was a reasonably close correlation between lesion size and tuberculin sensitivity, allowance being nade for the poorer relative performance of fast-growing strains vlhich my have been harvested beyond their optiml time, and for one strain that my have been insufficiently adapted to the medium. In comparison with other strains, the Prague strain gave consistently
lower tuberculin reactions than would have been predicted from the lesion sizes. It was stated that the Prague strain had been adopted because
vaccine prepared with the Danish strain had given a too high complication rate. It was also agreed that no well-controlled study on the virulence
of various BOO strains in mn had yet been carried out. The virulence of strains in animals was discussed and data from studies in har.lSters 13 ,14 indicated that of the twelve strains compared
with Danish 1331, one was found to be more virulent, six were less virulent and five were approximately the same. The ranking of highest and lowest
virulence agreed with a similar ranking on the basis of allergenicity in children. It was concluded that this virulence test of'f'ered a useful guide
to the risk of untoward reactions in newborn children.
I I
-ll-
Data on virulence in guinea Pigs 15 wel"e thendescr1bed.
The
two test
procedures involved the recovery Ofvlilble l3CG organisms from guine8. pig spleen after intravenous injection of vaccine and the observation of' paralysis, death and the presence of viable :BCG organisms in the brain after intra-cerebral injection. The results from both test procedures showed the Swedish. French (ll73) and Danish (1331) strains to be more virulent than the Japanese (172), RUssian (3522) and English (FlO) stra10i, a ranking which was similar to that obtained by the tests in hamsters. Supporting data on the rate of gain of body weight of the guinea pigs confirmed the Japanese stre.in (172) to be the least virulent and the De.nish (1331) the IlX)st. A test for protective effect in animals 16 was reported. Vaccines
from nine strains were tested in guinea pigs which were challenged '\or.lth ~.
tuberculosis H37Rv three. six and nine weeks after vaccination, The French strs.in (1173) gave the highest protection and the Unpublished results from a guinea pig A comparison of
respectively.
Japanese strain· (172) the lowest.
study performed in another laboratory were mentioned.
the dose of various vaCCines, the reaction to tuberculin Rr23 twelve weeks after vaccination and its protection (by weight of spleen) six weeks after challenge, demoristrated that assessment of vaccine prepared from different strains, particularly at a low dose level, could be gauged by means of the post-vaccination tuberculin allergy induced. The protective
effect (by weight of spleen) showed that a vaccination dose of 50-100 viable units irrespective of vaccine strain used seem to protect the guinea pigs equally well. The relative doses - allergy relationships for living As would be
and killed BCG in man and in guinea pigs - were discussed.
expected the living organisms induced allergy in lower doses than the
-l2-
ki~led ones and the guinea pigs were shown to be far mol~ sensitive to the allergenic effects of BOG vaccine than man. The last paper18 on protection in bank voles of some l3CG strains was presented. Eleven BeG strains were examined and the protection in bank
voles was correlated with the virulence in hamsters :for eight of the stre,ins. 2.6 Choice of BOG strain and doses The discussion on the choice of a BeG strain for vaccine production and the dosage in which it should be used led to the following conclusions: (a) That the rate of waning of tuberculin reactions after vaccination was not a suff~cient guide to a vaccine's effiescy in the field. (b) That in the absence of a suitable test in man reliance must be placed upon tests of the protective effect of vaccine in animals (guinea pigs~ hamsters or voles). (c) That the virulence of a strain is not likeLy to be enhanced, but may be expected to fall as a result of repetitive BUbculture. This occurred in the esse of certain strains nOll in
use prior to the establishment of primary seed-lots. Referring to the latter argument, and to the Mediesl Research Council's
trial in the United Kingdom (in which a substantial protection from BOG was demonstrated) it was agreed that a BOG strain should not be less active in a range of experimental animals (less virulent or of less protective power) than the strain used in this particular trialj or rather, not less
active than strain l33l~ a strain which (according to recent knowledge) is the most active among those derived from the now unidentifiable strain that was used in the trial. It was felt that, apart from strain 1331, this argument would permit the use of' such strains as the French 1173 and the Swedish. It was not yet
considered desirable to recommend the use of' any particular strain.
'.
- 13As regards the dose levels, it was agreed thB.t the risk of untoward reactions in in1'ants 17 could best be overcome by a sui table reduction in the dose recommended for children, rather than that a nanufacturer should contemplate the preparation of two vaccines whenever the elected strain was of a relatively high virulence. The discussion on this subject took place in the BOG I.e.boratory in Alabang Serum and Vaccine IBboratories. Dr Su:mpaico, Director of the
Bureau of Research and Isboratories, briefly described the activities of the Bureau. The participants were shown the BOG production area and the
preparation of vaccine was demonstrated (harvesting, milling and sterility test). The aDinal stable housing guinea pigs for the skin reactivity test
was inspected. 2. C( Other natters Simultaneous or combined vaccination with BOG and smllpox was the first subject discussed. A paperlO on an .experimental study of the effect of simultaneous vacc;l.nation with BeG and snallpox vaccines performed in guinea pigs and rabbits showed that simultaneous vaccination with the two different vaccines was as effective as vaCCination with the two on different occasions. The
incidence of untoward reactions was no greater when simultaneous' vaccination . was performed. One of the partlicipants felt that combined rather than This might not only
simultaneous vaccination should be studied further.
result in the logistic advantage of a reduction in field work but also overcome a reluctance in some areas for two vaccinations to be inflicted on snail Children. A study in animls and children with a combined vaccine performed eight years ago was described. The results in aninals (comparison of
simultaneous and combined vaccinations) were satisfactory as regards
_ 14 BCG-induced allergy but i t w.s noted that the local lesion following combined vaccination is often larger and in some of the aninals the sllBllpox scab did not heal normally until over one zoonth after vaccination. A sllBll number of children included in the study had been vaccinated by the multiple-puncture method with half a dose of BOG and double a dose
of snallpox (both vaccines freeze-dried with sodium glutamte).
No
difference was found in the BCG-induced allergy or smallpox protection 18te in these children compared with a group vaccinated in the conventional way, but a firm conclusion could not be drawn, due to the limited number of children. Some participants felt that the prospect of simultaneous vaccination being accepted in the field depended on the use of a multiple-puncture technique for BOO vaccine. The dermo-jet gun technique was proposed, but
it was indicated that this had not been as successful for BOG vaccination as the intradern:al method. Having considered the costs and organizational
problems of separate progra.mmes for smallpox and BCG vaccination it would be acceptable to combine the programmes if the multiple-puncture technique for :BeG vaccine permitted easier integration with the snallpox progranme. A paper presented. 20
on the importance of coverage of BeG programmes was
It was emphasized that no IIBtter how good the vaccine production
is in the laboratory, its handling and efficient use in the field becomes the decisive factor in raising the level of tube~culosis
control with BCG vaccine.
Five mjor points to increase coverage were considered: (a) the advantage of a freeze-dried vaccine in tropical areas, such as the South PacifiC, where the susceptible population are widely scattered; (b) the need to 81mplify the vaccination technique, the intradern:al injection being somewhat difficult to carry out, particularly in newborns; I
II I
.. - 1., _ (c) direct vaccination without a preliminary screening test, to facilitate the giving of BOG vaccine simultaneous~ with another va.ccine to appropriate age-groups; (d) the need to make BOO vaccination part of the routine activity of workers 01' the peripheral basic health units rather than of specia.l teams; and finally, (e) the need for greater support of the vaccination programme by the community. Data demonstrating the effects 01' constant or intermittent programmes were present on the coverage of BOG vaccination in various countries in the Western Pacific Region. Coverage w.s on the whole, fairly good but it 'Was Simultaneous vaccination with
obviously desirable to make it still better.
BOG and smallpox vaccines was now routinely practised in the whole of China (Taiwan) and Korea, and experiences over a period of four years appeared satisfactory, particularly in coverage of the susceptible population. However, some parents objected to their children receiving two vaccinations at one time. Some participants expressed difficulties in meeting the coverage set forth by the Regional Adviser OD Tuberculosis. They believed that the use
of freeze-dried BCG va.ccine would be able to help in increasing coverage. Keloids as a complication of BOG vaccination were discussed. formation is rather cOlIDllOn in the Western Pacific Region. Keloid
It was agreed
that two kinds of study were needed in order to collect more precise data: epidemiological, to establish the factors other than the properties of
BOG vaccines with which keloid formation may be correlated, and e;gerimental, to esta.blish the frequency of its occurrence in different ethnic groups.
-16It was reported that in 'rbailand up to O.5'fo protruding with a diareter
or
all vaccineen bave scars
or
more than 10 rom.
In an Australian report on
the choice of vaccination site, data were given on the incidence and treatment of keloids in one state. :By compa.rison w.i.th other countries in the
Region, the frequency of l..eloid fOI'llBtion as s complication of BeG vaccination is very low in Australia where the use of BeG vaccine is confined to those who s.re non-reactive to tuberaulin. Sore of the partiCipants had observed
that the larger the BOO vaccination lesions the higher the incidence of keloida, a finding which orfered an argwrent ags.inst direct vaccination. In discussing the question of revaccination, the Regional Adviser on Tuberculosis pointed out that although formerly reva.ccine.tion was offered to Children on the basis of the waning of BeG-induced tuberculin sensitivity, the regional progra!llIIle is now concentrated upon primary rather than secondary vaccine.tion. It was suggested that whenever possible, and if vaccination of revacc~tion
the newborn and infants is carried. out extensively, made s.t school-leaving age.
sbduld be
In the final analysis, the choice is determined
by the level of tuberculous infection in the country. The Regional Adviser On Tuberculosis summarized the policy of WHO as far as the setting up of new laboratories for the production of freeze-dried BOG vaccine is concerned: (1) There is no purpose to be served by WHO assisting in setting up new BOG production facilities in a country unless the government is undertaking an s.ctive programme for tuberculosis control by means of BOG va.ccination. (2) The vaccination programme must aim to achieve an epidemiologically significant coverage of the susceptible population of the country.
II II
(:?)
The cost of establishing local production must compare favourably
with that of procuring supplies from a larger well-establiShed lB.bora tory.
" - l¥, -
(4) Before a new local mnufacturtJ:lg: laboratory is established,
it
must show that i t is able to produce a vaccine at least comparable in quality with vaccines produced elsewhere. If these terms can be substantially met, WHO may support a request to UNICEF for mterial aid. The Organization believes, hOwever, that there As long
is oore uniformity if production is limited to a few laboratories.
as adequate supplies can be obtained from such laboratOries the establish.. ment of new ones must be carefully evaluated.
3.
REC~ONS
The following recommendations were mde unanioously: 1. A seed-lot system should be used in each laboratory undertaking the mnui'acture of BCG vaccine, in order that the risks of culture variation may be minimized. 2. Provision should be made by the World Health Organization so that laboratories wishing to obtain an established seed-lot from an external source may be assured of a sufficient and continuous supply.
3.
In the preparation 01: a liquid BOG vaccine, nanufacturing laboratories should adopt to the greatest possible extent the relevant portions of the WHO Requirements for Dried :BeG Vaccine.
4.
Further studies should be made of the techniques of freeze-drying, with the objective of preparing a still better vaccine,
5.
Freeze-dried Ya.ccine should be used more widely in view of its operational advants.ges.
6.
In testing the final products, as well as in the production of the vaccine, rore than one method should be used both for viability and for be.cterial nass, so that estinates of greater validity nay be obtained. Tests for opacity and oxygen uptake should be considered.
.. In addition, periOdic testing of the vaccine in the field should be undertaken in respect of BCG-induced 8.llergy, size of lesion and untowa rd effects. 7. Further studies should be nade of the protective eUects of different l3CG strains.
8.
Studies should be continued in the countries of the Western Pacific Region on keloid fornation as a complication of BOG vaccination.
9·
The next symposium on BeG vaccine production should be held in four to five years' time.
"
- 19 .ANNEX 1 LIST OF PARTICIPAm'S, .<;:ONSUI4'ANl'S AND SECBEIL'ARIAT PARrICIPANl'S Mr Chin-Wei Chou
Chief, BCG laboratory Taiwan Serum Vaccine laboratory Taipei, Taiwan Republic of China Chief, Biologics Division National Institute of Health
Dr Namoho Chun
Seoul Republic of Korea Chief, BCG laboratory Pasteur Institute Saigon Republic of Viet-NB.m Mr V.F. Davey
Deputy Director (Technical) Commonwealth Serum Laboratories Parskville, Victoria Australia Director, BCG laboratory Perusahaan Naga ra Bio Fa rna (formerly Pasteur Institute) Bandung Indonesia. Head, Bacterial Vaccine Department .-Perusahaan Nagara Bio Farna (formerly Pasteur Institute) Bandung IildOnes1a Chief, BCG Vaccine Section Queen Saovabha Memorial Institute Bangkok Thailand Chief, BeG Division Department of' Tuberculosis National Institute of' Health Shins gawa-ku , Tokyo Japan Direct::>r, BCG Laboratory Japa.n BCG Production Company Tokyo Japan
Mr M.S. Nasut10n
Dr A.J.J. Kaligis
Dr Sriprapai Phong-Aksara
Dr T. HashillDto
Dr Tetsuji Sawada
.>
_20_
Annex 1 (cont'd) Participants (cont'd) Dr uoaquin S. Sumpaico Director Bureau of Reses.rch and Iaboratories Department of Health Manila Philippines Director, BeG Vaccine Production BOG Vaccine Laboratory Guindy, Madras 32 India OBSERVERS
Dr J .C. Suri
Dr Alejandro A08.nan
Medics.l Specialist II Division of Tuberculosis Bureau of Communicable Diseases Department of Health Ma.nila Philippines Chief, BOG Laboratory Bureau of Research and Iaboratories Department of Health Alabang, Rizs.l Philippines Chief, BOG Vaccine Production Department of Health Djakarta Indonesia. CONSUIIl'ANl'
Dr Iluminada Sumpaico
Dr Johannes Sutal'jO
Dr K. Bunch-Christensen
Chief, BeG Department State Serum Institute Copenhagen Denmark SECRF1rARIAT
Dr J. Guld
Medical Officer Tuberculosis Unit WHO Headquarters Geneva Regional Adviser on Tuberculosis WHO Regional Office for the Western Pacific Manila
Dr J.C. Tao
-. -21.-ANNEX 2 LIST OF HORKJllG PAPERS.
1. 2.
WHo Elcpert Committee on Biological Standardization Eighteenth Report (1966), Wld.Hlth.Org:.. tech.Rep.Ser., 329 Requirements for biological sUbstances: six general requirements for the sterility of biological substances (1960), Wld.Hlth.Org. tech.Rep.Ser., .
200
WHb!TB Tech.Guide/67.6)
DeSi~
for in vitro assays of BOG products (Unpublished document. .
4. 5· 6.
Technical Guide for Assessment of BOG vaccination programmes (Unpublished document. WHO/TB/Tech.Guide/2 Rev.4.65) WHO Elcpert Committee on Biological Standardization (1965): Experimental data for the selection of a reference batch of BCG (Unpublished document. WHO!BS!862.65) . .
roducts 1967 1 68
LIST OF PAPERS PRESENTED
1.
J. Sumpai co, et a 1 (1969) Elcpe riences with the seed-lot sys tem (Unpublished paper)
2.
Ly-Thanh-Dang (1968) The effect of Tween 80 in liquid BOG vaccine by means of number of cuiturable rticles B.nd BCG:induced allergy in human beings Unpublished paper Nam.-ho Chun (1965) The influence of storage temperature on the viability of liquid BOG vaccine (Tuberc.Resp.Disease, vol. 19)
4.
u
II
(1965) Hai'mfUl effect of artificial light on the viability of liquid BOG'vaccine (Tuberc.Resp.Disease, vol. §2.) (1965)~~1 effect of difi'used daylight on tqe .viability of BOG vaccine (Tuberc.Resp.Disease, vol. 19)
n
II
6.
T. Sawada K. Bunch-Christensen, et al
(1969) The influence of the homo enization procedure on the viability in BCG vaCCines Unpublished paper)
8.
T. Sawada (1969) Study on d T ;:' and preservation of' BOG vaccine (Unpublished paper
.. -22Annex 2
(cont'd) List of Papers Presented (cont I d) 10. 11. J .C. Surl, et al (1969) Stability of freeze-dried BeG w.ccine under field co.ndJ.t1ons (lInpubJ.1sl:led paper) Nam-ho Chun (1968) Experimental studies of conditions for the manufacture of freeze-dried BeG vaccine in Korea (Unpublished paper) WHO (1969) Studies in children of tuberculin sensitivity and skin
-
12.
lesions after vaccination, for twelve different BCG strains (Unpublished paper)
•
K. Bunch-Christensen, et a1 (1968) The virulence of some strains of BeG for golden hamsters, Bu11.Wld.Hlth.Org., ,22, 821
14. 15. 16. 17.
n
"
et al (1969) The virulence of some strains of BeG for golden hamsters (A further study) (In press)
T. Hashimoto (1968) Virulence of BCG strains in guinea pigs (Unpublished paper) T. Sawada (1969) study on BCG strains: protective effect in
guinea pigs (Unpublished pB.per) J. Guld, et a1 (1955) Suppurative lymphadenitis following intradermal BCG vaccination of the newborn, Brit.Med.J.,
§2" 11, 1048 18. Ladefoged, et a1 (1969) Protection in bank voles Clethrionomys G. Glareolus Schreb. of some strains of BOO Unpublished paper) Nam-ho Chun (1969) An exper:lJnental study of the effect of simultaneous vaccination with BOO and smallpox vaccine, (Tuberc.Resp.Disease, Vol. ~ J.C. Tao
19·
•
20.
.. A. Practical arrangements 1.
-~
..
"E'{AWMION SUMMARY Fourteen questionnaires were completed by the participa.nts.
Reception at your arrival? Accommods.tion?
Satisfactor,y No answer
11
3
2.
Good - 10 Satisfactory _. 1 No 8.nswer 3 Yes Ho No 8.nswer Yes No No answer Yes No No answer
3.
Sufficient contact with WHO staff?
-
11 2
1
4.
Enough time for reading document?
_ -
10 1
3 3
5.
I.enguage difficulties?
10 1
B.
Preparation and organization of meeting
6. 7. B.
Sufficient advance information and documentation, and in good time? length of meeting? The choice of subjects well-balanced?
Yes No Too short Appropriate
4 10 1
-
13
Yes - 13 (one wish to include field examinations) No answer 1 Was the time s.l1otted Too Right little
Details of replies were as follows: Was the inclusion of Subject this sub.iect Too li"ssen- Usee! Use- No tia.l ful !less answer I much , 1. Adoption 0 2 0 of seed-lot 7 5 system 2. Prepara. I 0 0 6 tion of li- I 3 5 Cluid vaccine ' 3. Freezed"'rof",~
No
s.nswer
7
0
7 8 8
6 5 6
0 1
6
0
0
8
0 0
I
1
4. Quality control 5. In-vivo studies of strains 6. Choice of BOO strain and dose f
,
6
3
0 0 0
5 5 5
1 1
7 7
I 1
:5 :5
6 6
0 0
6 6
1
I
7
- 24 :. Annex 3 (cont'd)
.. Satisfactor,y Fair 11
9. C.
How did you find the mode of discussion?
3
Ii II
Results 10.
Are the conclusions reached valuable? Was the meeting successful in s.chieving the objectives?*
Yes No Yes No s.nswer
14
o 2
11.
12
*BCG w.ccine production problems and quality control of BOG vaccine
Seven of the participants added comments: (1) (2) 2 participants mean tha.t the laboratories more or less are using the same method for production and control.
"
4 partiCipants mean that they les.rn of other experiences B.nd will be able to adopt some new methods and thereby follow B more uniform and stB.ndardized technique. •
(3)
1 of the PB.rticipants mean that the consideration was achieved well, but the national authorities stand between and it would therefore be difficult to follow a.l1 recommendations. Yes No 1 year 2 years 3 years 4 years 5 years 10 yeB.rs
12.
Should this meeting be repeated? and after how long a time?
14 0 1 1
2 1
8 1 l
13.
Comments of participants: 1 - Asked the other participants to be more active in the discussions. 1 - Said that application of BOG (in the field) could have been included in the agenda, as a regular item. 1 - Suggested to expand the number of partiCipants with others who are concerned in lW.tters of BOG vaccine even from other regions. Also field workers probably as observers. 6 - Asked whether papers to be presented could be distributed at least the day before, if possible, earlier. Two of them asked i f the partiCipants could be requested in due time to preps.re papers for another meeting. 2 _ Said that it would be better to include hotels with moders.te prices.