Report on integrated mapping of neglected tropical diseases in Equatorial Guinea : Onchocerciasis, Lymphatic Filariasis, Loiasis, Schistosomiasis and Soil-Transmitted Helminthiasis

AFRICAN PROGRAIVIVE FOR ONCHOCERCIASIS CONTROL -sI REPORT ON By Prof. Louis-Albert TCHUEM TCHUENTE Temporary Advisor, Primary lnvestigator Dr. SamuelWANJI Temporary Advisor, Co-l nvestigator INTEGRATED MAPPING OF NEGLECTED TROPICAL DISEASES IN EQUATORIAL GUINEA (Onchocerciasis, Lymphatic Filariasis, Loiasis, Schistosomiasis and Soil-Transmitted Helminthiasis) - "- n{i i,l ,''\:. ;i'r rii f,i" l. ;, ' .' *(' in ','r '- I * 'flri!{' April 2008 I T id !i ',i il , . '{ \ .r,l;]lb 'ttl : t, ACKNOWLEGEMENTS Thls study was co-financed by the African Programme for Onchocerciasis Control (APOC), ExxonlVlobil, George Washington University and the Liverpool School of Tropical [Vledicine. APOC coordinated the field missions and provided invaluable technical and administrative support. We would also like to thank several persons who contributed with the collection of relevant information and data necessary for this report. ln particular, we are grateful to Dr. Pierre tVpele, WHO country Representative, the Vice-tVlinister of Education, the General lnspector of primary education, the General Director of Health, Dr. Anacleto Sima, National Director for the Control of Onchocerciasis and other filariasis, Dr Pedro Ndongo Asumu, National Director for the Control of Trypanosomiasis, the health technicians, staff and teachers in Equatorial Guinea, the APOC Director and staff in Ouagadougou. Our special thanks for Mr H. Zour6 of APOC for facilitating our two missions and for the preparation of the figures and maps in this report. Prof. L.A. Tchuem Tchuent6 National Coordinator National Programme for the Control of Schistosomiasis and lntestinal Helminthiasis in Cameroon P.O. Box 7244 Yaoundd Cameroon Dr. S. Wanji Associate Professor of Parasitology, University of Buea, P. O. Box 63, Buea Executive Director, Research Foundation for Tropical Diseases and Environment, P.O Box 474 Buea Cameroon Warning fn the obsence of on existing shapefilefor the districts of Eguotorial Guineo,the APOC team creoted one in on opproximote monner. The octuol delineotion of the districts could be slightly dif f erent from the representation in this report. a I TABLE OF CONTENTS LIS'[ OF ABTIREV|ATTONS/ACRONYMS........... ..................... II CoN'rsxr AND J usIFICATIoN ...................... OBJECTIVES 3 GENT,RAL tNFottN4ATroN ABour E,euAt ORIAL GutNtsA.... I 3 I Ceograplo, geontorphologl.', h.r,drologt, climate I 32 Admtnislralivedrvisions 1 3.3 Population ( 1991 censusl I 3 1 l'he ltealth s1'stetn 1 3 5 Tlte Educalion syslent 2 I\,IETIIODOLOGY PROCESS.. DISCUSSIoN oN scopE AND PLANNTNG oF THE suRVEys ............................... RESEARCH METHODOLOGy..................... 2 3 I Stttdt,orea and sampling 2 3 2 Troinrng of tnvestryators ond contpositton of sun,ev leant I J J Dara collccriou for L.vtrtplntic l:rlartosis 2 3.1 Dala colleclionfor Onchocerciasis and Loiasis . 2 3 5 Data collectionfor Schistosoniasis and Soil-Transntitled Helntinthiasis 6 2.t 2.2 2.3 2.4 2.5 6 ','.,..,7 ........8 ..8 9 9 .9 . t0 DATA ANA1ysts .............................. Cunlr-pNcrs AND LrMtrATroNS .................. FTLAI{tASIS..... ll t2 3.I ........ ...... ... . t3 3 1 I ll,,lGFIL survet) Prevalence of Lyntph6llg Tlariosis antigenaentia 3 I 2 lll:.1 RElllO Sane.t 3 I 3 R.-lPLO.l sru've.r' 3.2 SCHISToSoIvIIASIS AND SoIL-'IRANSMIT.IED IIEI-MINI'HIASIS.....,..... 3 2 1 l'revulertc ancl rtrtertsrties of Sclristosttniast.r 3 2 2 Prevqlence and tntensrlies of Sorl-Transntitted Llelminthiusis 3.3 NTDCO-ENDEMICITY........... 3 3 I Co-ettdentrcrA'L),ttryhaltc Filariasis, Onclncerciasis and Lotasts (Fig.2l) 3 3 2 Co-endenttc'rh, Scllistosotltiasis and Soil-Tt'ansnritled Jlelnrtnlltia.ts (Ftg 221 J J J Co-endentictn,of the 5 NTDs (Frg 23) .I CONCLUSIONS........ 5 llECOMr\{ENDATIONS.................... t3 t7 20 23 21 29 34 J-t J5 36 37 l9 LIST OF REFERENCES 40 I J J J I J 5 J lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gutnea List of Abbreviations/Acronyms African Programme for Onchocerciasis Control Community-Directed Drstributor Community-Di rected I ntervention Community-Directed Treatment with lvermectin Eggs Per Gram of faeces Geographic lnformation System Global Positioning System lmmunochromatographic card test lntervention Unit Lymphatic filariasis [\/ectizan@ Expert Committee / Technical Consultative Committee lVinistry of Health National Onchocerciasis Task Force Neglected Tropical Diseases Rapid Geographical Assessment of Bancroftian Filariasis Rapid Assessment Procedure for Loa loa Rapid Epidemiological Assessment Rapid Epidemiological IVapping of Onchocerciasis Statistical Package for Social Sciences Soil-Transmitted Helminthiasis Technical Consultative Committee (APOC scientific advisory group) Special Programme for Research and Training in Tropical Diseases World Health Organrzation see TDR APOC CDD CDI CDTI EPG GIS GPS ICT IU LF MEC/TCC II/OH NOTF NTD RAGFIL RAPLOA REA REIVO SPSS STH TCC TDR WHO WHO/TDR ll lntegrated Mapprng of Neglected Tropical Drseases rn Equatorral Gurnea Executive summary ln Equatorial Gutnea, onchocersiasis, or river blrndness, is one of the most prevalent parasitic diseases. The disease has major health and socro-economic repercussions, and constitutes an important public health problem in this country, particularly in the Bioko lsland. A successful vector eltmination was achieved between 2000 and 2005 by the African Programme for Onchocerciasis Control (APOC), leading to the elimination of black flies in the Bioko lsland. Building on this success, there was an urgent need to strengthen CDTI in order to achieve the objective of eliminating onchocerciasis as a public health problem and an impediment to social and economic development in Equatorial Guinea. With financial and technical support from APOC Management, the re-launch of CDTI in 2007 resulted in an improvement of treatment coverage up to 100% and 71.3o/o for geographic and therapeutic coverage, respectively. Based on these achievements, APOC in collaboration with George Washington University and Exxon-Mobil, undertook an integrated mapping for the control of major neglected tropical diseases (NTD) in Equatorial Guinea, including onchocerciasis, lymphatic filariasis, loiasis, schistosomiasis and soil-transmitted helminthiasis. To determine the needs and strategies of control, one of the prerequisite was to define the distribution and prevalence levels of the different diseases. Therefore, parasitological and rapid assessment surveys were conducted in selected villages/communities and schools all over the country. The villages were selected randomly in all districts of the country. Cross-sectional surveys were conducted in rural and semi-rural communities (villages) from all districts (lntervention Units - lU) of the insular and continental regions of the Equatorial Guinea. lnvestigators were recruited amongst the health personnel from hospitals and health control programmes, and trained locally. Appropriate research methodologies were used for each of the specific helminthiasis; immunochromatographic tests for lymphatic filariasis, rapid assessment procedure for loiasls, nodule palpation (REA) for onchocerciasis, Kato-katz for intestinal schistosomiasis and soil-transmitted helminthiasis, and urine filtration for urinary schistosomiasis. The geographical coordinates of each of the sample villages were recorded with a global positioning system (GPS). A Geographic lnformation System (GlS) was used to plot the status (positive/negative) and prevalence each of the 5 helminthiasis for each sample community on a map. The different parasitological data were analysed using appropriate statistical test and methods. lll lntegrated IVlapprng of Neglected Troprcal Drseases tn Equatortal Gutnea Lymphatic filariasis antigenaemia A total of 3706 individuals (1592 males and 2130 females), aged from '15 to more than 85 years, were examined from 78 communities. Of the 78 communities,60.3 % had at least one positive case for ICT test. There was a great heterogeneity in the lymphatic filariasis prevalence between the '17 districts of Equatorial Guinea (P < 0.001).The overall infection prevalence per district ranged from }oh lo 12.4%. However, prevalence per community was up to 28.6%. Globally, LF prevalence was higher in males 5.9% (12711576) than in females 4.9% (9212130) (P < 0.001), and the LF prevalence was found heterogeneous amongst different age groups (P< 0.001). Onchocerciasis A total number of 2782 individuals ('1567 males and 1215 females) were palpated for nodules from 78 communities selected from all the 17 districts. All the 9 communities surveyed in the Bioko lsland were positive for onchocerciasis, one of them being hyper-endemic with prevalence above 40%. ln the continental region, of the 63 communities surveyed 6 were hyper-endemic for onchocerciasis (9.5%), 10 meso-endemic (15.9%), 17 with prevalence between 10 - 19.99% (27.0%),24 wilh prevalence < 10% (38.1%) and 6 were negative (9.5%). The prevalence of onchocerciasis by sex and age group is summarized in the Figure 6. Prevalence in males (19.9%) was higher than in females (9.3%). lndividuals > 45 years were found with more nodules than individuals < 45years (P < 0.001). Loiasis A total number of 4913 rndividuals (2060 males and 2853 females) were interviewed for RAPLOA from the 78 communitles. Only one of the 7 villages surveyed in the insular region had RAPLOA prevalence > 40o/o, whereas 58 of the 59 communities surveyed in the continental region had prevalence > 40o/o, with 52 of them exhibiting prevalence > 60%. There was a heterogeneity in the RAPLOA prevalence amongst the 17 districts (P < 0.00/). The results revealed the continental region of Equatorial Guinea as hyper-endemic for loiasis. The RAPLOA prevalence was hrgher in females than in males (P = 0.001, and there was a tendency for prevalence increasing with age (P < 0.00/); both in males and females. Schistosomiasis Of the 1376 children examined (756 males and 620 females, mean age 12.67 years),5.2% were infected by Schistosoma intercalatum, 0.5Yo by Schistosoma haematobium and O.2o/o by Schistosoma mansoru. The overall prevalence of schistosome infection (i.e. children infected by at least one of the three species of schistosome) was 5.8%. There was a IV lntegrated Mapping of Neglected Troprcal Dtseases rn Equatorial Gutnea significant variation of infection prevalence between schools/villages, districts and provinces (P < 0.001). However, there was no significant difference of prevalence between the sexes, nor between the age groups. S. intercalatum was the most prevalent schistosome species, with infection prevalence varying from 6.67% to 66.67%. Cases of S. haematobium and .S. mansoniwere found in only few schools, i.e. 5 and 3 schools, respectively. Soil-Transmitted Helminthiasis Of the 1376 children examined,72.2% were infected by Ascaris lumbricoides,9l.4% by Trichuris trichrura and 24.0% by hookworms. The overall prevalence of STH infection (i.e. chrldren rnfected by at least one of the three species of soil-transmitted helminth) was 95.6%. All the 94 schools investigated were positive for STH, and the infection prevalence was very high prevalence in 97.9% of these schools. Only 2 schools had STH prevalence < 50%. There was no significant difference of STH infection between the sexes and the age groups. The egg counts varied from 0 to 120,288 EPG for A. lumbricoides,from 0 to 72,000 EPG for T. trichiura, and from 0 to 23,040 EPG for hookworms, with an overall geometric mean of 277.4 EPG,248.8 EPG and 3.1 EPG, respectively. Apart from hookworms, there was no difference of mean intensities between males and females for each STH species. Co-endemicity Lymphatic filariasis is endemic in all districts in both the insular and the continental regions of Equatorial Guinea; loiasis occurs in all districts of the continental region; onchocerciasis is meso- or hyper-endemic in all districts of the Bioko lsland and in 6 districts of the continental region; soil-transmitted helminthiasis occurs in all areas of the insular and the continental regions; and schistosomiasis is found in 2 districts rn the Bioko lsland and in 11 districts in the continental region. lnterestingly, the results showed a wide co-endemicity of thre different helmrnthiasis over the Equatorial Guinea. Overall, in each of the 17 districts of Equatorial Guinea there was a co- endemicity of at least 3 NTDs. Co-endemicity of 4 NTDs (excluding onchocerciasis or schistosomiasis) occurs in 7 districts, and co-endemicity of all the 5 NTDs occurs in 5 districts in the continental region, i.e. Niefang, Evinayong, Akurenam, Ebebeyin and Nsork. Recommendations Considering the prevalence of the different helminthiasis and the high level of co-endemicity, the following recommendations are made: lntegrated Mapprng of Neglected Troprcal Dtseases tn Equatortal Gutnea A strategic plan for integrated control of lymphatic filariasis, onchocerciasis, loiasis, schistosomiasis and STH in Equatorial Guinea should be developed and implemented. Treatment strategies should be developed following WHO preventive chemotherapy guidelines. Before the mass distribution of ivermectin in the continental region for the control of onchocerciasis and lymphatic filariasis, special measures should be taken for the management of severe side effects, and strrct application of the MEC/TCC guidelines should be encouraged. APOC and partners should consider financial and logistical support to the implementation of the integrated control of NTDs in Equatorial Guinea. Synergies and co-implementations with malaria interventions (e.9. bed nets distribution) should be explored to increase funding opportunities from various partners rncludrng ExxonMobil. A road in tulongomo district Bisabat 2 health post ln A,4lsomeseng dlstrict \"1\ a ! ll, { i I ,: I ri-9- }}+': i&" lnvestigator and health worker at Bisabat 2 hea/lh post i*. Ir" .1," ,il I vt j , I r $ei" " t f '{al 1 Background 1.1 Context and justification The Republic of Equatorial Gurnea, one of the smallest countries in continental Africa, comprises a mainland territory, the island of Bioko and the island of Annobon. lt is the smallest country in continental Africa in term of population. ln Equatorial Guinea, onchocersiasis, or river blindness, is one of the most prevalent parastttc diseases. The disease has major health and socio-economic repercussions, and constitutes an important public health problem in this country, particularly in the Bioko Island. lndeed, the Rapid Epidemiological Mapping of Onchocerclasis (REMO) conducted in 1999 showed infection prevalence of 75% in the Bioko lsland and only20% in the tVlainland. Further REMO exercises conducted in 2002 by the National Onchocercrasis Task Force (NOTF), with technical and financral support from APOC, confirmed this trend, with prevalence varying from 15to73% in ruralvillages in the island of Bioko, and from 33 to 50% in selected areas of Malabo. Overall, 81% of rural villages and 91 .6% of Malabo areas had infection prevalence over 40o/o in the island and in tMalabo, respectrvely. Following the Rapid Epidemiological lVapping of Onchocerciasis (REIVO) by WHO/ApOC and inclusion of Equatorial Guinea as endemic country for onchocerciasis, two control strategies were adopted by APOC and the Government in 1998: the vector elrmination and the communrty-directed treatment with ivermectin (CDTI). Vector elimination - aerial spraying of insecticide combined with ground larviciding - began in 2000 and continued until lVay 2005 when the last large-scale larviciding spraying was conducted in Malabo city. Continuous entomological evaluations conducted in 2006 and 2007 conflrmed the absence of black flres, the vector of onchocerciasis rn the island of Bioko. APOC will continue monitoring the situation and hopes to announce the successful elrmination of vector black fly from the Bioko lsland. Community-directed treatment with ivermectin (CDTI) started effectively in 1999. However, therapeutic coverage has remained below the threshold of 65%, which is the minimum required in each community in CDTI priority area to have an impact on the transmission of onchocerciasis (Table 1). The low coverage is the result of poor sensitrzation and mobilization, and inadequate participatron of communities in ivermectin distribution. The last mass distribution of rvermectin was implemented in 2OO2 n Bioko lsland (in the rural area). lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea Building on the success of vector elrmination in the Bioko lsland, there was an urgent need to strengthen CDTI in order to achieve the objective of eliminating onchocerciasis as a public health problem and an impediment to social and economic in Equatorial Guinea. Therefore, a new strategic plan to re-launch CDTI was elaborated in early 2007 by the National Onchocerctasts Task Force (NOTF) of Equatorral Guinea with financial and technical support from APOC Management. Field activities started in June 2007 and training of health workers and Community-Drrected Distributors (CDDs)was achieved in July 2007. A total of 387 CDDs and 17 health workers were trained in the Bioko lsland. The trained CDDs were in charge of completing census and implementing CDTI activitres in all communities of the Bioko lsland. This resulted in an improvement of coverage up to 100% and 71.3% for geographic and therapeutic coverage, respectively (Table l). Table 1. Trainrng of health workers and CDDs in CDTI and ivermectrn distribution in Bioko lsland, 1999-2007. Year Training of CDDs and Health workers Population Treatment coverage (%)Communities CDDs HWs Total number Number treated Total number Number treated Geographical Therapeutic 1 999 2000 2001 2002 2003 2004 2005 2006 2007 40 140 140 194 12 12 12 12 129 129 129 129 '1 1,6 52,7 51,9 73,6 15 63 1'1 5 1 236 68 64 601 7 882 67 66 122 10797 95 67 679 10 874 No rvermectrn mass drstrrbution 128 70 903 48 551 No rvermectrn mass drstrrbutron No rvermectrn mass drstrrbutron 129 70 206 50 064 100 2,0 12,2 to,J 16,1 68,5 71 3 234 18 129 17 129 99,2 387 Based on these achievements, the African Programme for Onchocerciasis Control (ApOC) in collaboration with George Washington Universrty and Exxon-Mobil, undertook an integrated campaign for the control of some major neglected tropical diseases (NTD) in Equatorial Guinea. Th NTDs include onchocerciasis, lymphatic filariasis, loiasis, schistosomiasis and soil-transmitted helmrnthiasis. Polyparasitism is the norm rather than the exceptron in the developlng world - wrth most people infected by more than one parasrtic disease - and today there exist robust, low-cost and effective public health interventions to relieve parasitic infection burden and provide a better qualrty of life for people in poor communitres. The current strategy for NTDs control is to integrate interventions for multiple diseases. This integrated approach ensures cost- effectrveness and streamlin in g of rnterventions. 2 lntegrated Mapping of Neglected Troptcal Dtseases rn Equatortal Gutnea This inrtiative is built on the onchocerciasis control. However, there is the need to define the distributron and prevalence levels of the different diseases in order to determine the needs and strategies of control. APOC, therefore, requested Prof. L.A. Tchuem Tchuente and Dr. S. Wanji to advise and supervrse integrated mapping of the targeted neglected tropical diseases in Equatorial Guinea. 1.2 Objectives The main objective of the APOC consultants' assignment was to train the natronal health staff and coordinate the national integrated mapping of neglected tropical diseases (NTDs) in Equatorial Guinea, under specific objectives: . To review relevant NTDs control activities in Equatorial Guinea. . To plan in collaboration with the NOTF, MoH and WHO office in Malabo integrated mapping of NTDs in Equatorral Guinea. . To define with local authorities the best period of the year and the appropriate zones for the mapping exercises. . To define the needs and requirements for NTD mapping activities. . To train health technicians and field assistants on epidemiological surveys. . To supervrse the implementation of epidemiological surveys on onchocerciasis, loiasis, lymphatrc frlariasis, schistosomiasis and soil-transmitted helminthiasis in all districts of the island and mainland territories. . To submit a technical report on the rntegrated mapprng of NTDs in Equatorial Guinea. 1.3 General information about Equatorial Guinea 1.3.1 Geography, geomorphology, hydrotogy, climate The Equatorial Guinea is made up of two main regions: The continental region and the island region. The island region has two islands: Bioko and Annobon. The city capital is tt/alabo and rs situated in the Bioko lsland. Bioko lsland The Bioko lsland is an old volcano, with three important picks (Caldera - 2260 m, Biao -2009 m, Basile - 3011 m). The Bioko lsland rs also characterised by numerous streams which have their springs at higher altitude and which flow on stormy soil. These meandering rivers are fast flowing with numerous cascades which are excellent breeding sites for Simulium, vectors of onchocerciasis. The feet of the mountain are occupied by beaches with steeps. J lntegrated Mapprng of Neglected Troprcal Dtseases tn Equatortal Gutnea The clrmate of the Bioko lsland has a double influence of ocean and mountain, with important rainfall in the south-west flank and on the summits of the mountain. The locality of Ureka could register 6000 mm of rain fall per year. On the Bioko lsland, there are two seasons: the dry season from November to February and the rainy season from March to October. Annobon lsland The Annobon lsland, also known as Pagamu, is located in the South Atlantic Ocean. lt measures about 4 miles long by 2 miles wide, with an area of about 63/4 square miles. lt has a population of about 5000. There is no regular shipping service between Annoban lsland and the rest of Equatorial Guinea, and ships call as infrequently as every few months. Continental region The continental region, also known as Rio lVuni is characterised by a varied landscape, going from the coastal region in the west, to the hilly area in the centre region of the country and the swampy valley in the eastern part of the country. The country stretches out from latitudes -3'south (Bio campo) to -6" south (Asobio). ln the coastal area there are several estuaries where the rivers from inland flow into the sea. The inland is characterised by mountains with altrtudes varying from 600 to 1000 m. The most important summrts are: Alen, lVlitra, Bere and Nzas. These hills are at the origin of cascades on the rivers. Cascades are found in the following rivers: river Campo, river Wele, river Nrlitemele. These fast flowing nvers can be potential breeding sites for Simulium. The southern parts of the country have numerous swampy valleys, which can be potential breeding srtes for mosquitoes, vectors of malaria and lymphatic frlariasis. Also, rn the south- west coastal regron are the small islands of Mbelobi and Corisco. The climate of the continental region is characterised by four seasons as evidenced by the records of the rain fall at Bata. There are two dry seasons and two rainy seasons. The main dry season is from December to February and the shorter one from July to August. The main rainy season is from March to June and the shorter one from September to November. 1.3.2 Administrative divisions The country has two regions: the continental and the island regrons. The island region has three provinces: the province of Annobon, which covers the island of Annabon; the provinces of Bioko south and Bioko north, situated rn the Bioko island. 4 lntegrated tVlapprng of Neglected Troprcal Drseases rn Equatoflal Gurnea The continental region has four provinces: the centre south province, the Nkie Ntem provrnce, the littoral provtnce and the Wele Nzas province. The Provinces are further divided into drstricts. ln total there are 1B drstricts in Equatorral Guinea. 1.3.3 Population (1994 census) The populatton of Equatorial Guinea is estimated at 406,15'l inhabitants (1994 census): 315,625 rn the continental region and 90 526 in the island region. The population distribution is summarized in Table 2. The littoral province, rn the continental region is the most densely populated with 100,047 people. The less populated province is Annobon with 2820 inhabitants, while the Bioko Sur has 1 2,569 inhabrtants. About 61% of the population of the Equatorial Guinea lrve in rural areas. The average population density is 14.5 inhabitants lkm2. 1.3.4 The health system The organisation of the health system follows the pattern of the administrative divisions with: . Health centres or health posts at the village level, ' District hospitals at the headquarters of districts ('lB district hospitals), ' Provincial hospitals at the headquarters of provinces (7 provincral hospitals), ' Regional hospitals at the headquarters of regions (situated at Malabo and Bata). 1.3.5 The Education system The education system in the Equatorial Guinea is organised into primary, secondary and higher education. The primary education comprises 848 schools, made up of 600 government primary schools and 248 private primary schools. Overall, there are 1440 teachers. During the ,l999-2000 academic year,73,310 children attended primary schools, representing 86% of school age children. The secondary education consists of 5'l secondary schools (27 public colleges and 24 private colleges), with 920 secondary school teachers. ln the 1999-2000 academic year, 20,671 children attended secondary schools in Equatorial Guinea. The National University of Equatorial Guinea was established in'1995, with one campus in Bata and another one in Malabo. The university has'15 departments, with 16 specialities, 5 lntegrated I\Iapprng of Neglected Troprcal Drseases rn Equatorial Gurnea including health sciences, agriculture, engineering, administratlon, education, arts, lrterature etc. During the 1999-2000 academic year, some'1 328 students were registered at the unrversity, at different levels, programmes and departments. Table 2. Populatron of Equatorial Guinea per region, province and distrrct. ADMINISTRATIVE UNITS TOTAL URBAN POPULATION RURAL POPULATION INSULAR REGION Province ANNOBON -Dstrrct Annobon Provrnce BIOKO NORD -Drstrrct Baney -Dislrtct Malabo Province BIOKO SUD -Dstrtct Luba -Drctnct Rraba CONTINENTAL REGION Provrnce CENTRE SUD -Distrrct Akurenam -Dstrict Ewnayong -Distrrct Niefang Province KIE NTEN/ -Dstrrcl Ebebiyrn -Districl Milomeseng -Dstrict Nsoc Nsomo Provrnce LITORAL -Distrtct Bata -Drclrict Cogo -Distncl Mbrnt Provrnce WELE NZAS -Dslrict Aconbe -Dislricl Anisok -Dtstrict Mongomo -Dstrtct Nsork TOTAL 90526 2820 2820 75137 /0698 64439 12569 9242 JJZ / 3 1 5625 60341 1/637 21353 z/Jc/ 92779 45557 )ooE" 1 7269 100047 7/406 74607 14034 62458 9065 zzo tJ 23756 7024 4061 5 1 73376 2820 2820 66676 DOt I 60065 3880 JJZJ qq7 84372 9632 10) I 518 / 2530 11724 8075 2723 926 53762 50023 1309 2430 9254 /75/ 2105 4639 759 157748 17150 846 1 4087 4374 8689 5919 2770 23'1253 50709 9710 /6/72 24827 81055 37482 27230 /6343 46285 21383 / 3298 1 /604 53204 7314 20508 19117 6265 248403 2 Methodology 2.1 Process The participatory approach was considered very important for the success of the assignment. Within the framework of the assignment, two missions were conducted in Equatorial Guinea by the APOC consultants: 6 lntegrated Mapprng of Neglected Troprcal Drseases rn Equatonal Gurnea the ftrst trip was from 14 to 23 July 2007 lo plan and organize with the Ministry of Health and WHO country office the NTDs mapping surveys, and the second trrp was from 10 February to 2nd tvarch 2008 was to carry out the epidemiologtcal surveys and determine the prevalence of NTDs in the rsland and mainland. 2.2 Discussion on scope and planning of the surveys Planning visit (/4 - 23 July 2007) To gather all relevant lnformation for the situation analysis, the assessment of the needs, the elaboration of the methodologies, and the planning of the NTD mapping surveys, several meetings were organised with key stakeholders, including: . WHO country Representative (Dr. Pierre tr/pele). . NOTF Coordinator (Dr. Sima Anacleto). . N/edrcal Chiefs of 3 health districts (Riaba, Luba and Baney). . Mlnister of health and social well-being. ' General Director of Health, ministry of health and social well-being (Dr. Gregorio Gori lVlomolu). ' Vrce-lVlrnister of Education, Sciences and sport (lMr. carlos Nsu6 otong). ' General Director of primary educatron, ministry of education, sciences and sport. ' General lnspector of primary education, ministry of education, sciences and sport. ln addrtion, the following activities were conducted: ' Participatton in the Meeting of the National Onchocerciasis Task Force (NOTF). The WHO/APOC consultants made a presentation to the meetrng on the situation of neglected tropical diseases in Equatorial Guinea, the progress achieved such as vector eliminatlon rn the island of Bioko and the challenges for NTDs control. The importance of dlsease mapping and the arms and expected outcomes of the visit were also highlighted. This meeting provided an opportunity to advocate for NTDs control to important stakeholders. ' Teleconference with the National Coordinator of schistosomiasis control, Dr. pedro. ' Fteld visits in two health distncts (Baney and Luba) and discussron with the respective medlcal chiefs and health staff. ' Search of documentation in libraries, bookshops and purchase of relevant books. t 7 lntegrated lVlapprng of Neglected Troprcal Drseases rn Equatonal Gurnea The rationale and obJectrves of the assignment, opportunity for eradicatron of onchocerciasis and other NTDs were explained to the stakeholders. This was followed by drscussions on various aspects of the neglected tropical diseases including the situation of disease control, the health system and the availability of information required for the development of a work pla n. lnformation was gathered on health system, health personnel, equipment, logrstics available and on ongoing disease control programmes. Field suruey visit (10 February - 2nd March 2008) Before the start of the field work, the consultants had further meetings with relevant stakeholders rn Equatorial Guinea, rncludrng the country Exxonl\rlobil Public Affairs lVanager (tMrs. Leigh A. Evans), to explain them: . the scope and focus of the epidemiological surveys, . the study zones and study populations, . the research methodologies, . the field programme. Logistrc arrangements were also finalized. 2.3 Research methodology ln order to assess the levels of infections and the distributron of the different specres of helminths in Equatorial Guinea, parasitologrcal and rapid assessment surveys were conducted rn selected villages/communities and schools across the country. The villages were selected randomly in all districts of the country. Though the surveys for the different parasitic infections were conducted simultaneously in an integrated approach, specific sampling, specimen collection and parasitological methodologies were used for the different helminthiasis. 2.3.1 Study area and sampling Cross-sectional surveys were conducted in rural and semi-rural communities (villages) from all districts (lnterventlon Units - lU) of the insular and contlnental regions of the Equatorial Guinea. Withln each dlstrict, 2 to 8 villages were selected randomly. On the basis of a list of villages of Equatonal Guinea downloaded from the internet (GEOnet Names Server), an initial list of villages to be covered by the surveys was established using a 20 km x 20 km sampllng grid. When freld constraints arose, new villages were selected depending on the total number of villages within a given district. On average, 10% of communities within a 8 lntegrated Mapprng of Neglected Troprcal Diseases rn Equatorral Gurnea district were selected for the survey. Selection was made such that all lUs were entirely covered spatially. 2.3.2 Training of investigators and composition of survey team One-day training workshops were organised in [t/alabo for the insular region and then in Bata for the continental region (see Annex for the list of trainees). Trainees were recruited amongst the health personnel from hospitals and health control programmes. During training, special emphasis was made on the objectives of the surveys, the use of different rnstruments and survey forms. Six teams were constituted for the surveys: 3 for filariasis and 3 for schrstosomiasls and soil- transmitted helminthiasis. Each survey team was made up of 5 persons with speciflc tasks, including 2 individuals for RAGFIL, 2 for RAPLOA and 1 for REA for filariasis; and 1 investigator, 2 microscopist-technicians and 2 supporting technicians for schistosomiasis and STH. Each survey team targeted two communities per day. 2.3.3 Data collection for Lymphatic Filariasis ln each sampled village 50 resident adults (aged > '15 years)were tested for day-time filarial antigenaemia, using commercral rmmunochromatographic tests (lCT; Weil el al., 1997). A 100-pl sample of finger prick blood were collected from each subject, with a micropipette, and then dropped on an ICT card (Binax, lnc., USA). The reading was done within 3-5 mlnutes. Sample was deemed negative if the card indicated a negative result after '15 min. A resident adult was defined as a person who has been resident in the village for at least 10 years and who had not been absent for more than 6 months during that period. All surveys were conducted by country teams that were trained at the regional levels. The work was done under the supervrsion of international experts. The geographical co-ordinates of each of the sample villages were recorded with a global positioning system (GPS). A geographic information system (GlS) was used to plot the status (positive/negative) of antigenaemia for each sample community on a map, as well as the correspond ing prevalence. 2.3.4 Data collection for Onchocerciasis and Loiasis The study population consisted of males and females aged 15 years and above for loiasis, and 20 years and above for onchocerciasis, who have been resident in the vrllage for a mlnlmum of five consecuttve years for loiasis and ten consecutive years for onchocerciasis. All eligible members of the community who consented to participate were enrolled into the study. 9 lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea Conduct of the rapid assessment procedures for loiasis and onchocerciasis (RAPLOA and REA) Organbation of work ln each study community, the two RAPLOA investigators move from one household to another to recruit eligible participants, and administer the RAPLOA questionnaire. Eligible indrvlduals for REA were sent to a central point were the nodule palpation took place. Three forms were used for data collection. Two forms for RAPLOA and one form for REA. For RAPLOA, the community questlonnarre form was used to collect information on the existence of the eye worm migration phenomenon in the community and the local term used for the condition. The rndividual questionnaire form was used to obtain rnformation on the eye worms phenomenon experienced by interviewed indrviduals. For REA, the form was used to record the presence/absence of nodules for each individual palpated. Administration of RAPLOA questionnaire The Rapid Assessment Procedure for Loiasis was based on the restricted definition of the eye worm; the past experience of eye worm, confirmed by a photograph of L. loa adult worm in the white part of the eye and with the duration of the most recent episode berng between one and 7 days (Wanji et al 2005). The questionnaire was administered to 80 adults in the Spanish language and where required, interpreters from the community assisted in the interview process according to the RAPLoA guidelines (wHo/TDR, Geneva, 2oo2). Nodule palpation (REA) The REA was based on nodule palpation. After undergoing the RAPLOA interview, male and female patrents, above twenty years, and who have been rn the communlty contlnuously for the past ten years, were examined for the presence of onchocerca nodules. The geographical coordlnates of each of the sample villages were recorded with a global posttioning system (GPS). A Geographic lnformation System (GlS) was used to plot the prevalence of loa loa and onchocerciasis for each sample community on a map. 2.3.5 Data collection for Schistosomiasis and Soil-Transmitted Helminthiasis To assess the levels of infections and the dlstribution of the drfferent species of schtstosomiasis and sotl-transmitted helminthrasis in the 17 districts of the Broko lsland and the continental region of Equatorial Guinea, parasitological surveys were conducted ln schools in the selected villages; wrth the approval of the administrative authorities, school inspectors, directors and teachers. 10 lntegrated l\4apping of Neglected Troprcal Drseases rn Equatonal Gurnea The school children were invited to participate in the study, and were registered only after explanation of the objectives of the study to them and to their parents, teachers or guardian, and after full informed consent had been obtained. A total of 94 schools were surveyed; 10 schools in the Bioko lsland and 84 schools in the continental regton. Parasitologrcal infections were assessed using the Lot Quality Assurance Sampling techniques (Brooker et a|.,2005). ln each of the 94 schools, urine and stool samples were collected from 15 children selected randomly, preferentially from the 5th grade. A total of 1392 pupils from these schools were registered and included in the study. ln the Bioko lsland, all urine and stool samples were transported to the laboratory rn lValabo, whereas in the continental region samples were transported to the laboratory ln Bata for examrnation. All samples were processed the same day of collection, and no preservative was used. Urine and stool samples were collected in 60 mL plastic screw-cap vials, between '10.00 and '13.00 hours. ln the laboratory, each urtne sample was agitated to ensure adequate dispersal of eggs, 10 mL of urine was frltered through a Nucleopore@ filter, and the filters were examined by microscopy for the presence of schistosome eggs. Stool samples were examined by a srngle thtck smear technique using a 41.7 mg Kato-Katz template. Each kato slrde was read twice; immedlately after stool preparation for hookworm eggs, and the following day for schtstosome and other STH eggs. However, it should be noted that because of logistic constraints it was not always possrble to examrne all slldes wlthin 30 mrnutes and therefore hookworm prevalence and abundance are likely to be underestimated. lmportantly, the same Kato slides allowed for the detection of both intestinal schistosomiasis and soil-transmitted helminth infectlons in the study populations. 2.4 Data analysis The different parasitological data were analysed by the epidemiological unrt of ApOC using approprtate stattstical test and methods. The data were subsequently exported into SpSS version 13.0 for descriptive statistical analyses. Chr-square test was used to investigate the relationship between prevalence of infections and sex, age group, district and province. The geographical co-ordinates of each of the villages surveyed were recorded with global positionrng system (GPS) untts. A geographic information system (GlS) software (ArcGlS verslon 9.2, ESRI lnc.) was used to plot the prevalence of the rnfections for each sample vrllage on a map. 1l lntegrated tt/lapprng of Neglected Troprcal Drseases rn Equatorral Gurnea 2.5 Challenges and Iimitations The period for the field studres was too short, and to properly carry out the activities the research teams worked day and night and also during the week-ends. lnittally, 90 communittes were targeted for this study, selected from the Health tMapper software data base of the Equatorial Guinea; 10 communitles from the Bioko island and B0 from the continental region. However, in the field, rt was realised that several of the targeted communities were no more tn existence. A new sampling procedure was therefore adopted and the study communities were selected in each health district from the local map of the distnct. lr, f ;fft i i, - "\f7' Community members wating for examinalion Registration of community members mrT,i', i-- '1 'ft I Co/lectlon of b/ood by finger pick E-r Supervision ICT test @ t:l Nghl examrnallon to confirm presence/absence of LF lr. ,ta I' rul, , ;-rll ,l ql'jt',,ii"t^ l,:r "l li, 12 \.. I 7 I{ttu tri:-r lr liI ! I an " j"r j@ P, \ ,), ,it" tl t'.1 lli ,ll \ Il lntegrated Mapprng of Neglected Troprcal Diseases rn Equatortal Gutnea 3 Results 3.1 Filariasis The defined sample size for each of the three procedures were 50 individuals for RAGFIL, 30 indrviduals male or 50 individuals males and females for REA, 80 individuals for RAPLOA. ln several situations, these sample sizes were not reached due to lrmrted number of individuals available in communrties. A total of 85 villages were surveyed (9 from the insular region and 76 from the continental region). Because of the small size of sample from several villages, an attempt was made to regroup vrllages when the sample drd not reach the desrred srze and when the distance between these villages was less than 7 km. Thus, a total number of 78 communities were retained. ln presenting the results in this report, 'village' will refer to indivrdual vrllages vrsited while'community' refers to a village or two villages grouped in order to increase the sample size. 3.1.1 RAGFIL survey: Prevalence of Lymphatic filariasis antigenaemia A total of 3706 people were examined from 78 communitres. The distribution of the indrviduals in different age groups from 15 to more than 85 years of age is presented in Figure 1, wich shows that the distribution is close to a normal distribution. 2130 (57.5%) of the individuals examined were female and 1592 (42.5%) were male. Table 3 gives the number of male and female rndividuals examined in each of the study district and province. Also, Table 3 shows the number of communities visited per district and province. 15-24 25-34 35-44 45-54 55-64 65-74 7 5-84 85+ J Lr-(, E. o I(I, p .z! ; o OJ -o E fz 600 500 400 300 200 100 0 trMale trFemale Age group (years) Figure 1: Distribution of the individuals examined for RAGFIL per sex and per age group i I i' l3 lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea Table 3. Number of males and females tested, and communities visited per study district and province. Number of females and males tested Province District No. Yo Number of communities visited Females Males Total No.No. % Broko Norte Broko Sur Centro Sur Kre Ntem Lrtoral Wele nzas Baney Malabo Subtotal Lu ba Rraba Subtotal Akurenam Evrnayong Nrefang Sublotal Ebibryrn Misomeseng Nsok Nsomo Subtotal Bata Kogo I\,4brn r Subtotal Akonrbe Anrsok ltrlongomo Nsork Subtotal Total 63 38 101 9B 47 145 139 211 192 542 153 201 43 397 227 129 tbJ 5/9 139 113 125 49 426 2130 49.6 47.5 48.8 65.3 5 t.o 60.2 63.B 66.8 52.5 60.2 51 .2 57.6 44.3 53.3 caa 56 1 64.4 59.0 668 523 55.3 59.0 58.1 57.5 64 42 106 52 44 96 70 105 174 358 146 148 EA 348 170 '101 90 361 69 103 101 34 307 1576 504 52.5 51.2 34.7 48.4 39.8 36.2 aaa 475 39.8 48.8 42.4 EE 1 46.7 42.8 43.9 35.6 41.0 33.2 47.7 44.7 41 .0 41.9 42.5 127 80 207 150 91 24t 218 316 s66 900 ,oo 349 97 745 397 230 l5J 880 208 216 226 733 3706 2 2 4 3 2 5 E B 7 20 6 t1 2 t6 o 4 4 t7 4 5 5 2 16 78 Prevalence of communities with at least one positive case of LF Out of the 78 communities surveyed in the entire country, 47 had at least one positive case for ICT test, given an overall prevalence of 60.3 % (Table 4). The highest prevalence at the provincial level (81.3%) was recorded in the Wele Nzas province where positive indrviduals were found in 'l 3 communitres out of the 16 visited. The lowest prevalences were recorded in the two provrnces of the Bioko lsland: Bioko Norte (25%) and Bioko Sur (20%). Globally, the continental region displayed higher antigenaemia prevalence than the island region (65.2% vs22.2%, P= 0.018). 14 lntegrated lVlapprng of Neglected Troprcal Drseases rn Equatorral Gurnea Table 4. Community prevalence for lymphatic frlariasis in the srx provinces of Equatorial Guinea. Province Number of communities surveyed Number of communities positive Percentage positive (%) Broko Norte Broko Sur Centro Sur Kre Ntem Litoral Wele Nzas 4 5 20 16 17 Iu 1 1 14 11 7 13 23.U 20.0 70.0 68B 41 .2 81 3 Total 78 47 60.3 Prevalence of LF positive cases per districts and provinces Table 5 presents the prevalence of lymphatic filarrasis in male and female indivlduals in the dtfferent districts and provinces of the Equatorial Guinea. There is a great heterogeneity in the prevalence between the 17 districts (P < 0.001).The overall infection prevalence per district ranged from )ok in the districts of tValabo and Luba to 12.4% in the drstrict of Nsok Nsomo. However, infection prevalence per communrty was up to 28.6% (Fig. 2). There was a relative homogenetty in the LF prevalence amongst districts of the same province. ,f,1,;,1, C orrtftl rrrry lC T p rev.rlenc e (: 0 ir .$i: 0.01 - I 00 P r-orl nces lloultcl.tnes 0 rs:n ct l:oulrr:lart es P rrks , y,,'fr'' t,i. . il I illi'"1 L' . i'r ,i*- .il \ :'j I' ) o .. hir!.: !, ... t-; 'i .; ,1.[o'] $.. ; ,[.' 'r-[ ,r "ll,,irlllil;t -. rs_'..], r" , .,.f ic.:l r "r,-i ri il, i 1'''m,''i L _r_- i { r 1..} ',Jf'.:;? j:'t r. {, -."* [U ti:t 'iij +i.lili:rt lJJl Hu.$*{ ffi*+':'.'Jlg"'f,_$,tit{,1,,,1, '.t lffii' ; i-$ $n,"U,tr.$ e-r".,S ?.dra 6$t,m Fri{ilqf.tff [I]ril ru rfi i{fl!ffi3 fti.# fl[ffifi ffi_i fln".!(,;,i,"; t:ryffti,rll,rildfl ,lttrtt,q i, +"&id - - - l^ -r Flgure 2: Prevalence of lymphatic filariasis detected by ICT test in 70 communities of the Equatorial Gurnea where at least 33 individuals where tested. l5 lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea Table 5. Prevalence of lymphatic filarrasis detected by ICT test rn males and females in the different dlstricts and provinces. lnfection prevalence per sex Females Males Total otNo.No.No.No.No.No Number of communities visitedProvince District tested positive positive tested positive positive tested positive positive Broko Norte Bioko Sur Centro Sur Kre Ntem Lrtoral Wele Nzas Baney l\rlalabo Subtotal Luba Rraba Sublotal Akurenam Evrnayong Niefang Subtotal Ebrbtyin [,4 isomeseng Nsok Nsomo Subtola/ Bata Kogo Mbrnr Subtotal Akonrbe Anrsok Mongomo Nsork Sublotal 63 3B 10/ 9B 47 145 139 211 192 542 153 201 43 397 227 129 163 5/9 139 113 tzJ 4g 426 0 0 0 0 2 2 4 10 8 22 B 12 6 26 B 7 2 t7 6 4 12 3 25 0.0 00 0.0 0.0 4.3 1.4 2.9 4.7 4.2 4.1 5.2 bU 140 6.5 3.5 54 1.2 3.3 4.3 3.5 9.6 6.'r 5.9 64 42 106 52 44 96 79 105 174 358 146 148 54 348 170 '101 90 361 69 103 101 34 307 1 0 I 0 2 2 s 10 20 39 14 1B 6 38 6 7 6 t9 7 13 7 1 28 t.o 0.0 0.9 0.0 4.5 2.1 11 .4 9.5 11.5 10.9 9.6 12.2 11 .1 10.9 3.5 b.u 6./ 5.3 10.1 12.6 69 2.9 9.1 127 BO 207 150 91 241 218 316 366 900 299 349 o-7 745 230 253 880 208 216 226 83 733 1 0 I 0 4 4 13 20 28 6l ZZ 30 12 64 14 14 8 36 13 17 '19 4 53 0.8 0.0 0.5 0.0 4.4 1.7 b.u b.J 7.7 6.8 7.4 8.6 12.4 8.6 3.5 6.1 J.Z 4.1 A2 7.9 8.4 4.8 7.2 2 z 4 2 5 A o 7 20 6 I 2 16 9 4 4 17 4 E q 2 t6 Total 2130 92 4.3 1576 127 8.1 3706 219 5.9 78 Globally, LF prevalence was hrgher in males 53% (121t1576) than rn females 4.9% (9212130) (P < 0.001). The LF prevalence was found heterogeneous amongst different age groups (p < 0.001); and this heterogeneity was apparenfly more pronounced in males than rn females (E0.001 r/s 80.095) (Figure 3). lCl' carcl sltov'rng 1to.r i I it'a re s ul l .f or l, l: ,ffi,"i-ffir., t6 50 s ,!6 .G s .o 6 t o. E J o o o g 6 o l! lntegrated l\/apprng of Neglected Troprcal Drseases tn Equatonal Gurnea 20 15 10 Age group (years) Figure 3: Prevalence of lymphatic frlariasis detected by ICT test amongst males and females of different age groups. 3.1.2 REA/REMO Survey A total of 2782 individuals were palpated for nodules from 78 communltres selected from all lhe 17 drstricts of the country.1215 (43.7%) of them were females whrle 1567 (56.3%)were males. lndividuals examined were normally distributed amongst different age groups (Fig. a). 20-24 25-34 35-44 45-54 55-64 65-74 75-84 85+ Age group (years) Figure 4. Distribution of the individuals examined for REA per sex and per age group. 600 500 400 300 200 100 lrJd o o r!- 13 :: ; o oo E lz .t' i 15-24 25-34 35-44 45-54 55-64 65-74 75-84 85+ tr Male 4.6 8 5.8 3.1 12 10.2 't't.8 12.3 E Female 2.2 2.8 4.5 4 46 6.2 4.1 9.4 i- 17 0 lntegrated Mapprng of Neglected Troprcal Drseases tn Equatortal Gutnea Distribution of communities surveyed into different REA prevalence groups Table 6 and Figure 5 show the distribution of communrties surveyed into the different prevalence groups. ln the Bioko lsland, none of the 9 communrties surveyed was negative for onchocerciasis. One of them was hyper-endemic wrth prevalence above 40%. When the analysis is based on adult males only, onchocerciasis is meso/hyper-endemic in the surveyed communities of the Bioko lsland. ln the continental region, of the 63 communities surveyed 6 were hyper-endemic for onchocerciasis; 10 (15.9%) were meso-endemic, 17 (27.0%) exhibited prevalence between 10 and 19.99%, 24 (38.1%) had prevalence below'10% and 6 (9.5%)were negative. All the 6 communtties with zero prevalence in Equatorial Guinea were found in this region. The 16 meso- or hyper endemic communitres for onchocerciasis of the continental region were in the provinces of Centro Sur, Wele Nzas and Kie Ntem. Some areas in these three provinces are likely to be treated with ivermectin using the community-directed strategy, depending of loiasis level (see subsection 3.1.3). Nodule prevalence in males and females of different age groups The prevalence of onchocerciasis by sex and age group is summarized in the Figure 6. Males were found with more nodules than females: 19.9% (31211567) and 9.3% (11311215), respecttvely (P< 0.001). Regarding the age influence, individuals above 45 years were found wrth more nodules than individuals less then 45 years (P< 0.001). Table 6. Distribution, into different nodule prevalence groups, of lhe 72 communrtres with at least 20 individuals (males and females) examined. Province Number of communrties Number with prevalence = 0% Number with prevalence = 0.1 - 9.9% Number with prevalence = 10.0 - 19.970 Number with prevalence = 20.0 - 39.9% Number with prevalence = 40.0 - 100% Broko Norte Broko Sur Centro Sur Kre Ntem Litoral Wele Nzas 4 E 19 13 18 13 0 1 5 1 0 0 1 3 4 2 0 J 2 1 4 4 7 2 0 6 4 7 7 0 0 0 1 4 1 Total 72 6 25 20 14 7 % of communrtres o 35 z6 19 10 l8 lntegrated IVapprng of Neglected Troprcal Drseases tn Equatonal Gurnea o AI\ A o()* (n i'Fr (D o goo ,,8 o (l C ontntu ttrfr, n d ule pre,.,alence l: r ) - !'.S -'19.9 -39,e .100 ers Lakes P.rks ElrsEtcts bo und an es Pro,rrnces lt oun danes rlri 0 o A ryc o c o OC o C o c (}q\(l (\a O O() (t o (\ o o (} oc o o o C o cc o ,3 u0tt 0,1 G10 u20 t40 Rr,., o A O o()oo o +t-- I -' E Figure 5. Prevalence of onchocerciasis in 72 communities with at least 20 individuals (males and females) examined. Age group (years) Figure 6. Prevalence of onchocerciasrs determined by REA amongst males and females of different age groups. s .9 o o o oo o oc o o oo c C) G a) o- 40 30 20 10 0 ri r{ l I ,1 t, 20-24 25-34 35-44 45-54 55-64 65-7 4 75-84 85+ tr Male 14.5 93 16.1 21.4 20.6 25.1 2s.6 22.4 E Female 24 5.3 7.7 10 1 1.8 10.5 11.8 17 l9 lntegrated lVlapprng of Neglected Troprcal Drseases rn Equatorral Gutnea 3.1.3 RAPLOA survey A total number of 4913 individuals were interviewed for RAPLOA from 78 communities selected in all the 17 districts of the country.2853 (58.1%) were females and 2060 (41.9%) were males. The distribution of individuals amongst the different age groups above 15 years was close to the normality mainly for males (Figure 7). 600 500 400 300 200 100 oJd d o ! f tE; o E z 0 '15-24 25-34 35-44 45-54 55-64 65-74 75-84 85+ trMale trFemale Age group (years) Figure 7. Distribution of the individuals interviewed for RAPLOA per sex and per age group. Distribution of communities surveyed into different RAPLOA prevalence groups Out of the 7 villages surveyed in the insular region, only one had RAPLOA prevalence above 40% (Table 7). All the communitles with prevalence less than 20o/o were from the Bioko lsland. ln contrast, 58 of the 59 communities surveyed in the continental region had prevalence above 40%, with 52 of them (78.8%) having prevalence above 60%. The map of loiasis prevalence in the different communrtres is illustrated in Figure B below. Table 7. Dlstribution into different RAPLOA prevalence groups, of 66 communities with at least 40 individuals interviewed. Province Number of communities Number with prevalence = 0 - 19.9% Number with prevalence = 20.0 - 39.9% Number with prevalence = 40.0 - 59.9% Number with prevalence = 60.0 - 100% Broko Norte Bioko sur Centro Sur Kie Ntem Lrtoral Wele Nzas J 4 17 12 17 13 0 1 4 0 2 U 2 a 1 0 0 0 1 1 0 0 0 0 0 0 12 12 15 13 o//o 66 3.0 20 7.6 10.6 78.8 Total 752 52 lntegrated IVlapprng of Neglected Troprcal Drseases rn Equatorral Gurnea .;;fr * + ,illt -,[! tl crnlllr.ililt!, lrla lod llrer al e[ cp (:: I : '20 1 20 .39,!t9 r 40 - 59.99 + 60.100 P rrlv rn ces bor,r n cla rres 0 istrict ll ou n(lan es Pa rks *- it ,t[r ;l{ .k "{'rr '.d-r + -,,[ *t -4,: -+r r' ,fr .4" .d1n. rll .l{r I--E - - Figure 8. Prevalence of loiasis as determined by RAPLOA in 66 communtttes of the Equatorial Guinea with at least 40 individuals interviewed. RAPLOA Prevalence in different districts and provinces of the country A heterogeneity in the RAPLOA prevalence amongst the'17 districts surveyed (P < 0.00f) was observed (Table 8). The lower prevalences were observed in the drstricts of the Bioko lsland whrle higher prevalences were recorded in the districts of the continental region. ln none of the four districts of the Bioko lsland, did RAPLOA district-prevalence exceed 40%.ln contrast, all the districts of the continental region recorded RAPLOA prevalence above 60%. The continental regton of the Equatorial Guinea can therefore be considered as hyper- endemrc for loiasis. The RAPLOA province-prevalence follows the pattern of the RAPLOA district-prevalence. Wrthin a grven province, homogeneity was observed (P > 0.0q amongst RAPLOA district-prevalence, except in the Litoral province (p = 0.029. RAPLOA Prevalence in Males and Females of different age groups. The RAPLOA prevalence was hrgher in females than in males (P = 0.001. There was also a tendency for the RAPLOA prevalence to increase with the age (P < 0.007), this observation was valid for both male and female (Fig. 9). 2t I + lntegrated Mapprng of Neglected Troprcal Dlseases rn Equatorral Gurnea Table 8. RAPLOA Prevalence amongst males and females in different distrrcts and provinces of Equatorial Gurnea. Results of loiasis prevalence by sex Females Males Total Province District tested positive positive Broko Norte No. No. % No. No. % tested positive positive 62 '1 10 177 63 230 365 125 34.0 27.2 121 380 314 54 150 278 175 53.0 30.3 108 770 713 '148 100 0 67 6 233 '148 0 63,5 489 325.0 66.5 160 109 0 68 1 192 126 0 65 6 No. tested No. % Number of communities visited Broko Sur Centro Sur Kre Ntem Lrtora I Wele Nzas Baney Malabo Subfota/ Luba Rraba Subtotal Akurenam Evrnayong Nrefang Subtola/ Ebtbtyrn Mrsomeseng Nsok Nsomo Subtotal Bata Kogo IVbrnr Subtotal Akontbe Anrsok Mongomo Nsork Subtotal Total 65 tr2 118 '1 18 56 174 186 312 290 788 201 293 62 556 314 181 191 686 148 156 156 71 531 2853 '1 I 12 31 JO 58 129 187 183 499 '1 53 207 46 406 241 127 141 509 114 113 tt5 CE 397 1 900 292 226 26.3 322 357 33.3 694 599 63 1 63.3 /o I 706 127 116 243 239 110 349 294 460 523 1 277 361 485 30 JC 65 76 ?q 111 206 287 1n 4 824 lot JJC 13 f) 302 26.7 31 8 31 8 31 .8 701 624 OJJ 64.5 726 687 2 2 4 J 2 5 5 ,R 21 6 6 742 73.0 768 702 738 74.2 770 724 737 775 74.8 66.6 7B 430 200 121 115 436 82 153 124 46 405 2060 570 292.0 145 0 730 800 298.0 630 1100 870 330 293.0 1295 73 1 67.9 725 603 696 68.3 768 71 I 702 717 72.3 62.9 140 986 514 302 306 1122 230 309 280 tt/ 936 4913 103 698 386 200 807 177 aaa 202 8B 690 31 9s /J O 70.8 /f, I 662 722 71.9 770 722 721 752 73.7 65.0 2 14 8 5 18 4 4 E 2 16 78 ll I '15-24 25-34 35-44 45-54 55-64 65-7 4 75-84 85+ tr Male 47.4 56.5 58.3 63.2 71.5 656 74.5 71.8 E Female 44 609 68.7 68 73.1 77.7 758 83.2 s (! -9 6I o oo q, € o(! 100 80 60 40 20 0 Age group (years) Figure 9: Prevalence of loiasis determined by RAPLOA amongst males and females of drfferent age groups. 22 lntegrated Mapprng of Neglected Troprcal Dtseases tn Equatortal Gutnea 3.2 Schistosomiasis and Soil-Transmitted Helminthiasis Of the 1392 children registered,1376 (98 9%) provided both urine and stool samples. The mean age of children examined was 12.67 ! 2.84 years. The composition of the study populatron by age group and by sex is summarized in Figure 10 and Table 9. There were no signifrcant drfferences in pupil numbers between the sexes (756 males vs 620 females, P = 0.266). The sexes were also well balanced within age groups. missing 5-9 't0-14 15+ tr o =E a o o ! E z 600 500 400 300 200 100 0 0-4 tr Male tr Female Age group (years) Figure 10. Distributton of school children examined for schrstosomiasis and soil-transmitted helminthiasis per age group. Table 9. Composition of the study populatron by age and sex of children in Equatorial Guinea. Females Males Number Age group examined o//o Number examined Total numbero//o missrng 0-4 years 5-9 years 10-'14 years 15+ years 0 7 74 375 164 0.0 53.8 51 .0 43.5 46.3 2 t) 71 487 190 100.0 46.2 49.0 56.5 53.7 Z 13 145 862 354 Total 620 45.1 756 54.9 1376 z-) lntegrated Mapprng of Neglected Troprcal Dtseases ln Equalorlal Gutnea 3.2.1 Prevalence and intensities of Schistosomiasis Schistosomiasis prevalence and distrrbution by infection level groups Of the 1 376 children examined , 5.2% (n = 71) were infected by S. tntercalatum, 0.5% (n = 7) by S. haematobium and 0.2% (n = 3) by S. mansonrfhe overall prevalence of schistosome rnfection (i.e. chlldren infected by at least one of the three specres of schistosome) was 5.8% (n = 80). The results of the parasrtologrcal studres are summarized rn the Table '1 0. Table 10. Cumulative prevalence of schistosomiasis rnfection among school children in the districts of Equatorial Guinea. S. intercalatum S. mansoni s. haematobium Province District Number of No. children children examined infected Yo No. children infected Yo No. children infected % Broko Norte Broko Sur Centro Sur Kre Ntem Lrtoral Wele Nzas Ba ney Malabo Subtotal Luba Rraba Subtotal Akurenam Evrnayong Nrefang Sublotal Ebrbryrn IVlrsomeseng Nsok Nsomo Subtotal Bata Kogo Mbrnr Subtotal Akonrbe Anrsok lVlongomo Nsork Sublotal 00 00 0.0 00 00 0.0 00 06 00 0.3 00 00 00 00 0.0 00 00 0.0 10 00 00 0.3 00 07 00 0.0 00 'I 3 10 0.5 00 00 00 00 0.0 00 0.4 09 40 00 1.2 00 00 00 00 0.0 43 21 2 14.3 00 00 0.0 19 30 12 2.3 41 30 33 2 2.5 16 200 17 93 4 10 7 13.3 28 17 4 00 3 00 7 67 2 1.3 16 a1 56 45 zo 71 105 165 B4 354 75 135 30 240 235 7E 105 415 60 45 105 30 240 43 21 2 14.3 00 00 0.0 10 24 12 1.7 1a 22 JJ 2.1 196 40 00 11.8 17 00 00 67 1.3 1 I 0 0 0 1 4 1 6 1 J 1 5 z J 5 2 5 5 9 1 7 I 0 0 0 E 1 I 1 4 1 6 47 7 1 55 1 0 0 2 3 0 0 0 0 0 0 1 0 0 1 0 1 0 1 2 3 0 5 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 1 1 2 0 0 0 0 0 7 11 6 24 46 J 0 49 1 0 0 2 3 Total 1 376 71 5.2 3 0.2 7 0.5 80 5.8 94 Out of the 94 schools examined, 61 (64.9%) were negatrve for schistosomiasis, 24 (25.5%) had low prevalence, 7 (7.4%) had moderate prevalence, and only 2 (2.1%) exhibited high prevalence (Table 1'1 ). ln Bioko Sur province, schistosome infectrons were absent. 24 Schisfosomiasis Num ber No. of children schools infected % visited lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea Table 11. Distribution of schools/villages by schistosomtasis prevalence groups Province Number of schools Number with prevalence = 0% Number with prevalence = 0.01 - 19.99% Number with Prevalence = 20 - 49.99o/o Number with prevalence = 50 - 100% Bioko Norte Bioko Sur Centro Sur Kie Ntem Lrtoral Wele Nzas A tr 24 16 28 16 2 5 17 10 13 14 0 o 0 0 2 0 1 0 0 0 f) 0 2 0 7 6 7 2 Total 94 61 24 7 2 % 64.9 25.5 7.4 2.1 Schistosomiasis prevalence by sex, age group and village Detailed analysis of the results showed significant variation of infection prevalence between schools/villages, drstricts and provrnces (P < 0.001). There was no signifrcant drfference of schistosome rnfection between the sexes: prevalence of 5.6% (421756) in males and 6.1% (381620) in females (P = 0.651). There was also no significant difference between the age groups (P = 0.379) (Figure 1 1). 15 10 Age group (years) Figure 11. Prevalence of schistosomiasis by sex and by age group 20 5 0 s .2 E o o I I 6 o o oo I 6 o(! lL il -' -.1 ;' <=4 ycars 5-9 years 10-14 years 1 5+ years trMale 0 8.5 6.2 3.2 E Female 0 5.4 6.9 4.9 25 t. lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea Figure 12 shows there was a significant difference of schistosome infections between schools/villages. Of the 33 schistosome-positive schools, the lowest prevalence was 6.67% in Bososo in the Bioko Norte district, and the highest was 66.67% in Barrio lkunde in the Bata district. S. intercalatum was the most prevalent schistosome species. lnfected children were found in 29 of the 94 schools investigated, with infection prevalence varying from 6.67% to 66.67% (Fig. 13). Very few cases of S. haematobium infections were found in 5 schools (Fig. 1a) and those of S.mansoni in only 3 schools (Fig. 15). f ln*t ilillfl 1' itl;r #,'.'I..1 F sch ool scht stcrs0 lll fi st 5 pre'r.rl ence (:: ) 0 . ..., 0.i:t'l _ 10rar Pro,it nces l:ou nrlar res Drstflct bounr:ianEs Pa r1i s dilfl {r,r*+it'.r,,-,ffi ri-S:} i.ir;fC.;'t t-;,., ) '"'\ j: . ..'.iii I'il lq l| L ,- , -lr-ili(,llilllili r[, " ---l-- € l) repuru t i on rl .tu rrr p I e s -/br ttricro:;c'opic' erutttinaltott tn lltc lubordlotf irt Botu , " ,1 fry4 \i;TL. I i" ,flqnqrF+ i/ F1tiligi/ lr f/illtlI Mru :..,,f,[ Frgure 'l 2. Prevalence of schistosomiasrs in school children in Equatorial Guinea ,ri ' - 26 # { lntegrated IVapprng of Neglected Troprcal Drseases ln Equatonal Gurnea #:, .o Scho ol S, rnterc.ll.ltu nt p re,r al ence (::' : 0:: e 0.01 - 19,99:: st 20 - 49.99:r $J so, too., Pror,rn ces bo urrclanes Drstn ct l:ou nd anes P ai- ks IIA :j Jlr s, dr * ,[[ r ilt, llh s, 4 lxtr ,il, l" d. -t1--r-E Figure 13. Prevalence of S. intercalatum in schoolchildren in Equatorral Guinea Jr Sch00l S, haenrat0lltunt prErdlpnce (:: I :0 . 0,01 .'19,!! ,;5. 20 - 100 Pro,.,tnces I:oun clan es Drstflcts boundarres Parhs s. a'J -:r--- Figure 14. Prevalence of S. haematobium in school children in Equatorial Guinea 27 School S, nrarrsolri prevalerrce (0,1 ) _0 i 0.01 - '1 t-ttl Prov irrces lrcurrcl.rries Districts lrcundaries Parks lntegrated Mapprng of Neglected Troprcal Dtseases ln Equatortal Gutnea ,.il ,I ,d[ -r-, + Figure 15. Prevalence of S. mansoniin school children in Equatonal Guinea lntensities of schistosomiasis Since there were too few cases of S haematobium (only 7 children infected) and S. mansoni infections (only 3 positives cases), statistical analysrs was carried out only on S. intercalatum. The egg counts for S. intercalatum ranged from 0 to 2520 eggs/g of faeces, and the overall arithmetic mean was: . 15.64 !62.20 in Bioko Norte province, . 1.90 ! 21.44 in Centro Sur province, . '18.60 t 180.01 in Kie Ntem provrnce, . 31.03 t 148.56 in Litoral province and . 8.60 ! 122.59 in Wele Nzas province. No case of schrstosome infection was found in Bioko Sur province. 28 lntegrated f\/apprng of Neglected Troprcal Drseases rn Equatonal Gurnea 3.2.2 Prevalence and intensities of Soi!-Transmitted Helminthiasis STH prevalence and distribution by infection level groups The results of soil-transmitted helminth infections are summarized in the Table 12. Of the 1376 children examined,72.2% (n = 993) were infected by Ascaris lumbricoides, gl.4% (n = 1257) by Trichuris trichiura and 24.0% (n = 330) by hookworms. The overall prevalence of STH infection (i.e. children infected by at least one of the three species of soil-transmitted helminth)was 95.6% (n = 13'15). Children were infected wrth STH in all the 94 schools examined, with very hlgh prevalence in 92 (97.9%) of the schools. Only 2 schools had STH prevalence < 50% (Tabte t 3). Table 12. Cumulative prevalence of soil-transmitted helminth infections among school chrldren ln the distrrcts of Equatonal Guinea. A. lumbroides T lnchuria Hookworm srH Province Dtstrict Number of children examined /o Number of children infected % Number of children infected Number of children infected Yo Number of children infected Number of schools visited Broko Norte Broko Sur Centro Sur Kre Ntem Lrtoral Wele Nzas Baney Malabo Sublotal Luba Rraba Sublolal Akurenam Evrnayong Nrefang Subtolal Ebrbryrn Mrsomeseng Nsok Nsomo Subtolal Bata Kogo l\,4brnr Subtotal Akonrbe Anrsok I\,4ongomo Nsor k Sublolal 23 33 56 45 lo 71 105 165 84 354 135 30 240 105 415 60 45 105 30 240 20 20 40 11 12 87 135 74 296 54 89 17 160 tb3 59 77 301 58 30 bt) 19 173 870 606 71.4 244 46.2 32.4 829 81.8 88 1 83.6 72.0 659 567 66.7 70.2 787 /J.J 72.5 96.7 bb. / 629 bJJ 72.1 23 27 50 20 23 43 98 153 80 72 127 21 zzo 207 66 100 373 60 43 101 30 234 100 0 81.8 89.3 44.4 88.5 60.6 93.3 92.7 ota 93.5 96.0 94 1 900 94.2 88.1 88.0 952 89.9 100 0 956 96.2 100 0 97.5 0 1 I 0 5 5 22 59 16 97 16 29 11 56 38 34 3.1 103 17 8 31 12 68 00 3.0 1.8 00 19.2 7.0 21.0 3s.8 19 0 27.4 Z I,J 21 5 30/ 23.3 162 45.3 ?O A 24.8 28.3 17.8 295 400 28.3 23 28 51 aa 46 103 164 84 351 131 28 234 221 73 103 397 60 44 102 30 236 100 0 84.8 91.1 489 o?? 64.8 98 1 994 100.0 99.2 100 0 97.0 93.3 97.5 94.0 07? 98 1 95.7 100 0 s7.8 97 1 100.0 98.3 2 3 5 3 2 5 7 11 6 24 9 2 16 17 4 7 28 4 3 7 2 16 Total 29 1376 993 72.2 1257 91.4 330 24.0 1315 95.6 94 lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea Table 13. Distrrbutron of schools/villages by soil-transmitted helminthiasis prevalence groups Province Number of schools Number with prevalence = 0o/o Number with prevalencg = 0.01 - 19.99% Number with prevalence = 20 - 49.99% Number with prevalence = 50 - 100% Bioko Norte Broko Sur Centro Sur Kie Ntem Litoral Wele Nzas 5 E 24 16 28 16 1 0 0 0 0 n 0 1 0 0 0 o 0 0 0 0 0 0 4 4 24 16 28 16 Total 94 0 92 o//o 0.0 1.1 1.1 070 s IF a 0) o o G)o trI(! C) o- STH prevalence by sex, age groups and villages For the three helmtnth species there were srgnifrcant differences between province (P<0.00/). There was no significant difference of STH infection between the sexes and the age groups (Figure 16). i,lj; t, I - .:,. r,a' ir illilr ,'i i'i ', , lfix 'i,rl ... 7.,,1 ...-j;;i" r'{i,i,, Iihil ,.-,"1] ,,; <=4 5-9 10-14 15+ tr Male 100 98.6 94.7 95.8 E Female '100 93.2 94.7 99.4 Age group (years) Figure 16. Prevalence of sorl-transmitted helminthiasis by sex and by age groups. Figures 17-20 show the variation of sorl-transmitted helminth infectlon prevalence between schools/villages. Helminth infections were found rn all schools; the lowest overall STH prevalence was 6.67% in Moka-lValabo in the Luba district, and the highest was 100%. The large malority of schools (70%) exhibited a prevalence of 100%, i.e. all children in these 66 schools were infected with STH. 100 80 60 40 20 0 30 .,. i 1l :il lntegrated Mapping of Neglected Troprcal Drseases rn Equatorral Gurnea , [ .. *+1 [tJ t:r'{ilr;i p.l jr It": ti i i School STH ;:rev.rlerrce (10' Prov irrces Ircrrrrclaries D is tricts t:orrrrdarles Parks ffl rnrr-r fi]#,#ild# tlmil ff.TEirT Ur::.! i r,; *r'4Hf:l'L{i'!":.i t:'.i{.,--.: [jffi,*i t-ll- r:; ffim;"" ,*Jl['i[ r:5 " I lDUr& -;, . ._ ,jtrE r1 6Aat F:T i#J HU[ ru., ., fi'T .J*'"' dl, , [#it ,iiI"v, *'#,lfu r*l L' 'i F -{ 6.;1 u,r-l . n*:l;nilfl ffiJ flrfl r-- .r rl.lJ tmill!fi rJLI ITf,ii f*l EudHffi i'{ l![i,lll lxt, itirr,ll Er: iiU sl I" l'$!-..; ll T," I ils# ',t w @ ,m,lfrffi r ffi fif]ffi*' ft-T rl,T ffi'ff--l:# U*:i'* ffi* flililffitffiffi ffi ffi 'lt lr)r 1 Figure 17. Prevalence of soil-transmitted helminthiasis in school children in Equatorial Guinea. tI{ u[ B jr ! ffiu &r I E ;11,, ^t IIGE r E;tr \ m /fo.d U U ffiI UU Sch ool A. lu nrbn c0rdes 1tre,r al en ce (:r :0 * 0.01 - 19, lt9 & 20 - 4B,gg E 50-100 Pro,.,tn ces llo u nd an e s DrslncLs boundarres Parks ffi I E H E TE rE k, E u s, @; BE*E wffi E I--Y Figure 18. Prevalence of A. lumbricoides in school children rn Equatorial Gurnea JI MT E Ea E Ji ut lL ill lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea ilill ,.1 L [,.r " 'Li l7.?!.l. Ir' flllu l1F '-1 all tr uxm Ju g1 [.,,i gg "-j m &^r !u ri.ll m il mmli"J J,--, JJ j.. 4,, L a tt. ,* riil rn tuflI uilF'sE,-.J ,t "x!-Jiil l! ri" i- r,1.." f nlr;J J UUtJ ' li EI li,$ i I Id J t ,' tl utfiSchaol T, tlchrura prE,.,alEnce '- l:J . r1.01 - 19.09 L 2l-l - 4!1, gg titiffi 50 . 100 Pro,r ln cES l: otrrr d arres Dtstrrcls [:ound.tnes Fa rl"s (=, ! 1 .l ,.I\i ffi; !I u i,il1i,r ta!i",i illl Hi[]U t -, 11 kI il IIr\ [Lil u"r__. I r ".:i --## Figure 19. Prevalence of T. trichiura in schoolchildren in Equatorial Guinea ilrtll il[ '* 6Jlu E:t I ,fi" ,1 A A .^fi- A. lr School hcrokv,,ornrs llrev alence ( io ) ^ 0,01 -19.939; ,,l,{, 20 - 49.950,i m 50 - 100q; Prov inces borrrrrlaries Dis tricts l:ourrdar les Park s ffi# ih tl ,l lr, Llz A ltu ffi [ri u .&,& .&J.r A a "i:r" .{ Jltl,, .q & "[l[ fllll T Jit ,At tF--r Figure 20. Prevalence of hookworms in school children rn Equatorial Guinea -l-,I )Z rj ,. lntegrated Mapprng of Neglected Troprcal Dtseases rn Equatortal Gutnea lntensities of STH infections The infection rntensities of the drfferent species of STH by sex and age groups are summarised in Tables 14 and 15. The egg counts varied from 0 lo 120,288 eggs per gram (EPG) for A. lumbricoides, from 0 to 72,000 EPG for T. trichiura, and from 0 to 23,040 EPG for hookworms, with an overall geometric mean of 277.4 EPG,24B.B EPG and 3.1 EPG, respectively. Detarled analysis revealed no drfference of mean intensitres between males and females for A. lumbricoides (P = 0.331) and I trichiura (P = 0.502). However, there was a significant drfference between sex for hookworms, males exhibiting higher infection load (P < 0,00n. Table 14. lntensities of sorl-transmitted helminthrasis by sex rn school chrldren in Equatorial Guinea. Geometric 95% Confidence lnterval for geometric mean mean minimum maximum Lower Upper A lumbricordes T tnchrura Hookwonns Female lVale Female lVlale Female lVlale 248.8 303.2 745 5 681.4 1 08000 120288 72000 46560 23040 4224 183 9 232 6 617 0 569 6 336 5 395 3 900 7 815.0 0 0 0 0 U 0 2.4 38 2.1 3.2 28 4.4 Table 15. lntensities of sorl-transmrtted helminthiasis by age group in school children in Equatorial Guinea. Geometric 95% Confidence lnterval for geometric mean mean minimum maximum lower upper A lumbricotdes T. trichiura Hookworms 0-4 years 5-9 years 10-14 years 15 years + 0-4 years 5-9 years 10-14 years 15 years + 0-4 years 5-9 years 10-14 years 15 years + 655 330 1 248 8 346 7 48 182 4 192 5 237.8 889.6 597.3 321.7 505.4 U 0 tl 0 25800 6'1680 120288 38640 11280 41280 72000 28800 558.0 515.9 613 9 490.7 1320.1 757 5 726 I 628.2 3123 3 1112 0 860.7 804 4 25 29 32 30 480 480 23040 3360 0.6 2.1 28 24 97 40 J./ a-7 48 0 0 0 0 0 0 0 JJ lntegrated tVlapprng of Neglected Troprcal Dtseases rn Equatorral Gutnea 3.3 NTD co-endemicity 3.3.1 Co-endemicity Lymphatic Filariasis, Onchocerciasis and Loiasis (Fig. 21) Lymphatic filariasls rs endemic in all districts in both the insular and the continental regions of Equatorial Gulnea; and is co-endemic with loiasis in all districts rn the continental region. Loiasis occurs in all drstricts of the contrnental region, and is co-endemic with either lymphatic filarrasis or onchocerciasrs, or both. Onchocercrasis is meso- or hyper-endemic: . in all districts of the Bioko lsland, where rt rs co-endemic with loiasis; and . in the districts of Nrefang, Evinayong, Akurenam, Ebebeyin, lVlongomo and Nsork in the continental region, where it is co-endemic with both lymphatrc filariasis and lorasis. flhnllirrrfitil1m I,-.-. , ,".".ri,i.,1!,! - L= "*j. ili;'l,ili l:lncr'or:ir!r,r:r: - Li - lcr-t:rs !F - 13,i!1s Lr-<i,rat: li. Jna,il :: rr-I - E Figure 21. Co-endemcity map of onchocerciasis, lymphatic filariasis and loiasis in Equatorial Guinea )+ lntegrated Mapprng of Neglected Troprcal Dtseases rn Equatortal Gutnea 3.3.2 Co-endemicity Schistosomiasis and Soil-Transmitted Helminthiasis (Fig. 22) Soil-transmitted helminthiasis occurs rn all areas of the insular and the continental regions. Apart from the distrrcts of Anisok and [Vongomo rn the continental region, and the districts of Luba and Riaba in the rnsular region, schistosomiasis occurs in all other districts and is co- endemic with STH. ' S r - J'-'llai::r'llll!: irilrtis i:!L,nJ,iflis 't .II - - - Figure 22. Co-endemicity map of schistosomiasis and soil-transmitted helminthiasis in Equatorial Guinea .l lr c'r osc'op it' e.\ o ntt nol t o n h.t' t eutrt ttrc tttbers Jtw I hrl I *i .-. *t*---- .- 35 'l i I I .iflry 'l 't g ;JffItil- lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea 3.3.3 Co-endemicity of the 5 NTDs (Fig. 23) Co-endemicity of the 5 NTDs occurs in 5 drstricts rn the continental region, i.e. Niefang, Evrnayong, Akurenam, Ebebeyin and Nsork. Co-endemicity of 4 NTDs (excluding onchocerciasis) occurs rn 6 districts in the continental region, i.e. Bata, Mbinr, Kogo, Nr'licomeseng, Nsok Nsomo and Akonibe. Co-endemicity of 4 NTDs (excluding schistosomiasis) occurs in 1 district in the continental region, i.e. [Vlongomo. Co-endemtcity of 3 NTDs (LF, lotasis and STH) occurs in 'l drstrict in the contlnental region, r.e. Anrsok. q 0.a-.t ,ll (;0 q |l l' : sl"::: L c"f J,i, :-r (* rfi (- :: -:nrrr,,iiJ r.:i,I ::^,-is : Scltrsli ic rrrr-lsrs g, 4!r" r l Evf il ---------ri.;.j i rl -'tr,-r;rr-f'r-dr! - !- ::l j:lij - r,:^.;i L:is,s - := - ri,,r -F -,a n: s L(* IIEI I E Figure 23. Co-endemicity map of onchocerciasis, lymphatic filariasis, loiasis, schistosomiasis and sorl-transmltted helminthiasis in Equatorial Guinea 1l,Y' ilil , Parasdes n the faeces of school chtldren 36 o ir. "i .,.' r 11il r:. (l lntegrated Mapprng of Neglected Tropical Drseases in Equatorral Gurnea 4 Conclusions L ym p h a tic Fila ria s is ( Wu ch e rerlos is ) . Thts survey has demonstrated the antigen of Wuchereria bancrofti in the blood of the population of the Equatonal Guinea. ' Given the high specificity of the ICT test, there is no doubt lhal Wuchereria bancrofti is endemrc in this country. . Even though, the number of people found rnfected in surveyed communities was relatively low, the number of communities found with at least one positive case was high (80% of community surveyed in the Wele Nzas province had at least one positive case). This justrfres an intervention against lymphatic filariasis in the Equatorial Gurnea. Onchocerciasis ' This survey has confirmed the high endemicity of onchocerciasis in the Bioko lsland. ' The study has demonstrated heterogeneity in the prevalence of the disease in different districts and provinces of the continental region. ' lVleso/hyper -endemic communities for onchocerciasis were found in three of the four provinces of the continental region (i.e. Centro Sur, Wele Nzas and Kie Ntem). Loiasis ' RAPLOA has demonstrated a level of endemicity of Loa loa relatrvely low in the Broko lsland. Only one community out of nine surveyed had a RAPLOA prevalence reachtng the threshold of 40%. There is reason to think that most of the positive cases tn the island are immigrant from the continental region. The native of the lsland seem to not know much about the history of the eye worm, they drd not have local name for the condition rather. ' ln the conttnental region, RAPLOA demonstrated a very high level of endemicity for Loa loa. More than 80% o'f communities surveyed in this region had RAPLOA prevalence above 60%. ' This very high level of endemicity of L. loa exposes the population of the continental region to a high risk of developing severe side effects following ivermectin treatment for onchocerciasis and lymphatrc frlariasis. Schistosomiasis The study demonstrates that three species of schistososomes occurred in Equatorial Gurnea. However, s. mansoniand s. haematobium have very low prevalence (<'1 %), 3l lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gutnea and S. intercalatum is the predominant species (5.2%). lt appears that the schistosomiasrs prevalence has increased in comparrson to the level (3.7%) from the previous natronal surveys conducted in '199'1-1992 and in 1996-1998. . The highest prevalences are found in the districts of Malabo and Bata. However, drsease transmission in the Bioko lsland is uncertain and still to be clarified. Most of the positive cases in the island are probably immigrants from the continental region. Similarly, prevalence in some villages with very few cases of infectrons may be due to immigratron rather than active local transmission. S oi/- Tra ns m itted He lm r n th ias is . Overall prevalence of STH in school chrldren was very high (95.6%), with 97.9% ol schools exhibitrng prevalence greater than 50%. . STH infections were found in all villages and the large majority of schools (70%) exhibited a prevalence of 100%, i.e. all children in these schools were infected with STH. . The high infection prevalence and intensitres highlight the urgent need for rmplementrng dewormrng in all area of Equatorial Gurnea. Co-endemictty . The map of the different NTDs showed a co-endemicity of at least 3 helminthiasis in all districts of the Equatorial Guinea. . The 5 NTDs (i.e. onchocerciasrs, lymphatic filariasis, loiasis, schistosomiasis and soil- transmitted helminthrasis) are co-endemici in 5 districts in the continental region of Equatorial Guinea, i.e. Niefang, Evinayong, Akurenam, Ebebeyin and Nsork. ir{hL 1" fr J[, 38 :,llIlftir4ry1 liltr'11 * .ui i I li /4it9* lntegrated Mapprng of Neglected Troprcal Drseases tn Equatortal Gutnea 5 Recommendations Based on the results, the followrng recommendations are made: . The distribution of lvermectin + Albendazole against Lymphatic filariasis should be undertaken in the continental region of the Equatorial Guinea. . CDTI should be organised in the three provrnces where mesoendemic communities for onchocerciasis were found. . Before the mass distrrbutron of lvermectrn in the continental regron for the control of onchocerciasrs and lymphatrc filarrasis, special measures should be taken for the management of eventual severe side effects, and strict application of the MEC/TCC guidelines should be encouraged ". . De-worming for STH should be implemented twice a year rn all districts of the Equatorial Guinea. . The distrtbution of Praziquantel against schistosomiasis should be undertaken in all areas where positive cases were found. . A strategic plan for integrated control of lymphatic frlariasis, onchocerciasis, loiasis, schistosomiasis and STH in Equatorial Guinea should be developed and implemented. . Treatment strategies should be developed following WHO preventive chemotherapy gurdellnes. . APOC and partners should consider financial and logistical support to the rmplementation of the integrated control of NTDs in Equatorial Guinea. ' Synergies and co-implementatrons with malaria interventions (e.g. bed nets dtstribution) should be explored to increase funding opportunitres from various partners such as ExxonlVlobrl. , n l'OC to plor'iclc the lVlcctizan I\pcrt Corrrnittc-c/Tcchnical Consultative Conrmittcc guiclelines 39 lntegrated Mapprng of Neglected Troprcal Drseases rn Equatorral Gurnea List of References Brooker S., Kabatereine N.8., Myatt M., Stothard J.R. & Fenwick A. (2005). Rapid assessment of Schistosoma mansoni. lhe valrdrty, applicability and cost-effectiveness of the Lot Qualtty Assurance Sampling method in Uganda. Tropical N/ediclne and international Health, 10, 7, 647-658. UNDPAlVorld Bank/WHO Special Programme for Research and Training in Tropical Disease, Guidelines for Raprd assessment of Loa loa. TDR/lDE/RAPLOA/02.1 2002. Wanji S, Tendongfor N, Esum [V, Yundze SS, Taylor lVJ, Enyong P. Combined Utilisation of Raptd Assessment Procedures for Loiasrs (RAPLOA) and Onchocerclasis (REA) in Rain forest Villages of Cameroon. Filaria J. 2005 Apr 7;4(1).2. Well GJ, Lammie PJ, Werss N. The ICT Frlariasis Test: A rapid-format antigen test for diagnosis of bancroftian filariasis, : ParasitolToday. 1997 Oct;13(10):401-4 40 lntegrated [\ilapprng of Neglected Troprcal Drseases rn Equatorral Gurnea Annex List of nationals trained No Name 1 Santrago Esono 2 Raimundo Nguema Ondo 3 Nrcolas Ndong lt/abale 4 Maria Nieves Oyana Sima 5 Gabrrel Ava Ekwa 6 lgnacio Ngomo 7 Eustaguro Nguema Ndong Akeng 8 Clemencra Eyenga Nguema 9 Casiano [\4dong Mba 10 Fernando Javler Nguema 11 Alfonsrna Nchama 12 Urbano Monsuy Eyi 13 Esther Aguila 14 Juan Lurs Alfonso 15 Teodora alene Nfa Nchama 16 Luclano Ebane Ela 17 Enrique lVba Ondo 18 Elvrra Obono l\4bomio '1 9 Rosarro Angu6 l\/alongua 20 Antonrno Essono Anvene 21 IVaurina Nchama Nsue 22 lVlanuel Eyama lVlba 23 l\tlarra Reyes fi/lonayong Obiang 24 Vrctorra Anguee tVlba 25 Joaqurna l\4rkue Evuy 26 Rufrno Nguema Andeme 27 Susana lVbasogo Mba 28 Domingo Nze Ondo, ATS 29 lVaximo Miko Ondo, biologrste 30 Marra Del Prlar Akele 31 Ambrosro tVartrn lVlba, ATS 32 Polycarpe Ricardo Ncogo 33 Manuela Eyang lVba Category Schistosomrasrs and STH Schrstosomiasis and STH Schistosomrasrs and STH Schrstosomiasis and STH Schistosomiasis and STH Schistosomrasrs and STH Schistosomrasis and STH Schistosomrasis and STH Schrstosomiasrs and STH Schistosomrasis and STH Schrstosomiasis and STH Schistosomrasrs and STH Schistosomrasrs and STH Schistosomiasrs and STH Filariasrs Frlariasis Frlariasrs Filarrasis Frlarrasis Frlariasrs Filanasrs Filarrasrs Frlarrasrs Filanasrs Frlariasis Filariasis Frlarrasis Frlariasis Frlariasis Frlariasis Frlarrasis Frlarrasis Frlariasrs 41