1
WORLD HEALTH ORGANIZATION ORGANISATION TVIONDIALE DE LA SANTE AFRICAN REGION REGION DE L'AFRIQUE
ONCHOCERCIASIS CONTROL PROGRAMME IN WEST AFRICA PROGRAMME DE LUTTE CONTRE L'ONCHOCERCOSE EN AFRIQUE DE L'OUEST B P. 549 OUAGADOUGOU, Burkrna Faso Télégr . ONCHO OUAGADOUGOU Tél : 34 29 53 - 34 29 59 - 3429 60 Télex. ONCHO 5241 BF Fax' 34 2875
Original. English
REPORT OF OCP ACTIVITIES AND THE ENTOMOLOGICAL RESULTS IN THE OUEME BASrN (1978-2001)
By
Samuel A. SOWAH* and Hyacinthe AGOUA*
Under contractual service agreement with WHO/OCP
The first version of this report was written by Mr S.A. Sowah for the period 1978-1998. The document was reviewed and updated by Dr. Hyacinthe AGOUA until2001, with the collaboration of the Programme Director and the Chiefs of Units.
N" 123|02NCUTEC/3.9
*Medical Entomologists. Previously WHO-Oncho control Programme staff members
Ouagadougou, June 2002
30-07 -02 2 CONTENTS
I. INTRODUCTION
2. OVERVIEW OF THE ONCHOCERCIASIS CONTROL PROGRAMME IN WEST AFRICA
-) DESCRIPTION OF THE OUEME BASIN AREA
4 ENTOMOLOGICAL ACTIVITIES (EVALUATION AND VECTOR CONTROL)
4.1. Entomologicalsurveillance. 4.1.1. Breeding sites. 4.1.2. Catching points. 4.1.3. Entomological prospections.
4.2. History on larviciding. 4.2.1. Aerial larviciding. 4.2.2. Ground larviciding. 4.2.3. Insecticides used (Insecticides rotation)
4.3. Entomological results. 4.3.1 Vectors concerned. 4.3.2 Parasites concerned. 4.3.3 Transmission. 4.3.4 Special studies on S. soubrense Beffa form. 4.3.5 Entomological results on 3 1 -12-2001.
5. SURVEILLANCE OF AQUATIC FAUNA
6. EPIDEMIOLOGICAL EVALUATIONS
6.1. Epidemiological results before vector control. 6.2. Epidemiological results during vector control. 6.3. Latestepidemiologicalresults. 6.4. Recent ophthalmological evaluation.
7 IVERMECTIN DISTRIBUTION.
8 SOCIOLOGICAL INVESTIGATIONS.
9. POPULATIONS SENSITIZATION AND MOBILIZATION ACTIVITIES
10. DISCUSSIONS.
I1. CONCLUSION 3 1. INTRODUCTION
This report is written as a result of contractual service agreement entered into by OCP with the authors.
The aim of this report is to give a consolidated account of OCP activities in the Oueme river basin as well as the results obtained from the beginning of OCP activities to date.
The report should cover not only entomological activities but also all aspect of OCP activities such as, epidemiological investigations carried out (with their corresponding results), Ivermectin clistribution. sociological investigations if any, sensitisation carried out by OCP field staff. and any other relevant inforrnation available.
2. OVERVIBW OF THE ONCHOCERCIASIS CONTROL PROGRAMME IN WEST AFRICA
The Onchocerciasis Control Programme in West Africa started its activities in 1974 and covered 7 countries (Benin, Burkina Faso, Côte d'Ivoire, Ghana, Mali, Niger and Togo). Its original savannah area covered 654,000 km2. This was the area where the severe form of onchocerciasis resulting in blindness prevailed leading to the depopulation of the valleys. Following the extension of tlre Programme activities in Côte d'Ivoire in 1978-lg7g, the Programme area covered 764,000km2, which represents about 18,000 kms of rivers treated. In view of the good results obtained and in order to prevent reinvasion, further extensions were made southwards and westwards in 1987-1988. Currently, the Programme concerns 11 countries (Benin, Burkina Faso, Côte d'Ivoire, Ghana, Guinea, Guinea-Bisau. Mali. Niger, Senegal, Sierra Leone and Togo) and covers 1,300,000 t The Prograrnme aimed at controlling onchocerciasis to ensure that this disesase is no longer a public health issue. or an obstacle to socio-economic development, and also that countries involved are able to perpetuate this realisation. On the administrative level, the Head Office of the Onchocerciasis Control Programme ls based in Ouagadougou, Burkina Faso and includes the Administrative Unit, the Planning, Evaluation and Transfer Unit, and the Vector Control Unit. On the operational level. the Vector Control Unit is divided into two (Eastem and Western) zones with sectors, sub-sectors and operations bases which communicate through a radio network, which allows a rapid transmission of epidemiological data as well as scientific and administrative directives. In 1990. there were 5 sectors,20 sub-sectors and one antenna in Bandiagata, Mali in the original OCP area and its southern extension. The western extension counts 8 sectors and 25 operations bases. The Administration Board is the Joint Programme Committee (JPC) that includes representatives of programme countries, Sponsoring Agencies and delegates of 23 Donor Organisations and Countries. The Committee of Sponsoring Agencies (CSA) is composed of the World Health Organisation (WHO) that is the implementing agency of the programme, the Food and Agriculture Organisation (FAO) the United Nations Development Programme (LINDP) and the World Bank. As from the mid-9Os, a certain number of sectors, sub-sectors and operations bases were closed down due to the gradual reduction of some programme activities in view of the satisfactory results obtained in most river basins. OCP activities will end on 3l December 2002. 4 3. DESCRIPTION OF THE OUEME BASIN AREA The entire Oueme basin lies in the Republic of Benin. It stretches from latitude 10 degree North and enters into the Gulf of Benin at the coast of the Republic of Benin (fig. l), in a woody Savannah area known as the Dahomey Gap, where the Savannah type of vegetation stretches from the North of Benin right to the coast. There are two types of climatic conditions, giving two types of seasons, namely the rainy season and the dry season. The rainy season starts in the South around late March and in the North between mid May to mid June. The rainy season ends around rnid or end of October. This ushers in the Harmattan, which marks the beginning of the dry season. The principal tributaries of the Oueme are: the Alpouro, the Yerou Maro, the Wewe and the Terou in the North. In the middle portion are the Odola, the Beffa, and the Adjiro. In the South are the Okpara and the Zou. Hydrolog.v Generally, the main river and its tributaries flow mainly in the rainy season, namely from late .lune to the middle of October, with the peak around the month of September. From late October to the middle of November most of the tributaries stop flowing. The main river, however, continues to flow up to the middle of January. The discharge of the Oueme can be more than 1000 cubic metres per second. This was recorded in week 36 in 1998 at Atchakpa(frg.2). On the tributaries the discharge can be around 500 cubic metres per second. This was recorded at Atcherigbe on the Zou in 1999 in week 35 (fig. a). In the dry season, the entire basin dries up with no flow at all from the North to the area around Zagnanado where minor flow can be observed. Eventually these flows also stop a month or two before the onset of the rainy season. The Oueme river and its tributaries are devided into several stretches, according to the -OU irnportance of the tributaries and the discharge, 100, OU 400...etc. (fig. 8). 4. ENTOMOLOGTCAL ACTTVTTTES (EVALUATTON AND VECTOR CONTROL) 4.1 Entomological surveillance 4.1.1. Breedins points . ln order to make the work easer for the Aerial Operations team, nver sfrefches are coded by taking into account, the name of the river basin and adding a number from 100 to 900. For example : OU 100 and OU 400 means: Oueme nver, stretches : 100 and 400. 5 Oueme The S. damnosum s.l. breeding points on the Oueme itself begins from lat. 9 degrees 40 minutes north, a little bit downstream from Affon catching point. From this breeding point to the confluence of the Yerou Maro, six other important breeding points can be found (fig. 6). Eleven other major breeding points are found from Beterou (lat. 9 degrees 13 minutes North) to the confluence of the Odola (lat. 8 degrees 46 minutes north). Note that these points are identified only in latitudes because of the fact that the Oueme flows virtually from North to South, hence, the latitudes pinpoint to a particular point on the river. From the confluence of the Odola to the Atchakpa breeding point, eleven other major breeding points can be identified. The main complex breeding points on the Oueme are found between Atchakpa catching point and Aguigadji catching point. At this stretch (from lat. 8 degrees north to lat. 7 degrees 29 minutes north), the breeding points are virtually joined together with very few pools in-between. Below the Atchakpa-Aguigadji stretch apart from the complex breeding point at Tamiedji (lat. 7 degrees 25 minutes north). there are, practically, no natural breeding points. On the other hand occasionally man made fish traps can be found here and there (fig. 6). Alpouro Very few breeding points are found on the Alpouro, which are not important for S.damnosum s.l. breeding. Yerou Maro On the Yerou Maro also very few S. damnosum s.l. breeding points are found. The only important breeding point is found near its confluence with the Oueme. Wewe The breeding points on the Wewe are not many and are not important for S. damnosum s.l breeding. Terou There are very few breeding points on the upper stretches of the Terou, where the river flows from North to South. The important breeding sites are located frorn the confluence of the Aguimo to the confluence of the Terou with the Oueme. Odola One important breeding point on the Odola is situated near its confluence with the Oueme. Other minor breeding points are found upstream but these do not play important role in S. damnosum s.l breeding because of the short duration of flow of this tributary. 6 Beffa The uppermost breeding point on the Beffa is located lat. 8 degrees 48 minutes North. There are no breeding points down to lat. 8 degrees 39 minutes north. From this point down to the confluence with the Oueme twelve important breeding points can be found. It is important to note that S. soubrense Beffa form is named after this river since this specie was first discovered on this river Adjiro The principal breeding points about fifteen in nurnber, lie between longitudes 2 degrees East and2 degrees l5 minutes East around latitude 8 degrees 29 minutes North. Okpara Among all the tributaries of the Oueme, the Okpara is the tributary with the greatest number breeding points, for, at least, about one hundred and eighteen (118) principal breeding points can easily be identified. The majority of these are found between lat. 9 degrees 4 minutes North andlat. T degrees 53 rninutes North, where the Okpara forms the demarcation line between the Republic of Benin and Nigeria. The rest of the breeding points (about thirty-eight in number) are entirely found in the Republic of Benin. Zort The Zou lies entirely in the Republic of Benin and takes its source around lat. 8 degrees 27 nrinutes North, near a village called Pira and enters into the Oueme around lat. 7 degrees near a village called Gongbe. TheZou is considered to be one of the longest tributaries of the Oueme but has relatively fèwer breeding points compared with the Okpara. the other long tributary. The principal breeding points, twenty-one in number, are situated between latitudes 7 degrees 35 rninutes North and 7 degrees 20 minutes North. Downstream from the breeding point on lat. 7 degrees 20 minutes North. no more natural breeding points occur, except one or two man made fish traps which constitute artificial breeding points. The river itself flows very little at this stretch with the presence of lot of green algae Kouffo The Kouffo is not a tributary of the Oueme. It is a coastal river that springs in Togo in the legion of Dotoé on the east of the "Okéloukoulou Rocs" and enters into the Ahémé Lake in Benin. This river has two stretches: the stretch OU801, upstream Lanta that is located in a hilly area with breeding sites, and the stretch OU802 that is downstream Lanta. 4.1.2. Catching points. 4.1.2.1. Oueme 7 The total number of catching points on the Oueme itself along the years had been six. These are; Beterou. M'Betekoukou, Atchakpa, Affon, Aguigadji. and Zagnanado, in order of creation (fig. t). Beterou 1819 The first catch was made at this point by the Sub-sector of Natitingou in October 1976.The point was then passed on to the Parakou Sub-sector after the creation of the latter in 1978. The point has therefore been under the Parakou Sub-sector to date. Beterou, the hrst catching point on the Oueme, is regularly used as monitoring point to date. Atchakpa2703 Atchakpa was created in 1978 with the creation of the Sub-sector of Parakou. The first catch was made at this point in the rnonth of December 1978, and is being used regularly to date. M'Betekoukot2704 M'Betekoukou has a similar history like Atchakpa. It was created in 1978 and the first catch was made in the month of November 7978, and is still being used as a monitoring point to date. This point was first under the Parakou Sub-sector but passed on to the Bohicon Sub-sector in 1982. Affon27l0 Affon was created inl979 and the first catch was made in January 1979. This point was used regularly until Aplil 1986. Catching was stopped because of the low catches registered at this point and also because of economic reasons. In 1987 OCP had to take strong economic measures to stay within the budget. because of lack of funds. There was therefore reduction in VCU (Vector Control Unit) activities. This reduction affected certain number of catching points visited at that time. Affon was one of them. Aguigadji 2711 Aguigadji was created in 1982 and the first catch was made in September 1982. The point was flrst under Parakou Sub-sector but later on transfemed to the Bohicon Sub-sector in 1982. Since its creation Aguigadji has been a regular catching point to date. Zaenanado 3002 This point was created in 1982 with the creation of the Bohicon Sub-sector. The point was regularly used from September 1982 until September 1987. because of similar reasons already rnentioned under Affon. 4.1.2.2. Yerou Maro Barerou2T14 The first catch was made at Barerou in 1982 and has been used regularly to date. 8 4.1.2.3. Terou Wari Maro 2705 The only catching point on the Terou was created in 1978 and first catch was made in November same year, and has been used regularly as a monitoring point to date. 1.1.2.4. Adjiro Banon2107 Like Wari Maro, the Banon point was created in 1978. It is the only catching point on the Adjiro. The first catch was made in November in the same year and has been used regularly to date. 4.1.2.5. Beffa Vossa 2701 Vossa was created in 1978 with the first catching made in November and is still a monitoring point to date. 4.1.2.6. Okpara Binassi l9l8 Created in June 1978 and used regularly till 1987 Kaboua2702 Kaboua was created in 1978. The first catch was made in November same year and has been used regularly to date. Bassa 2706 The point was created in 1979. The first catch was made in June 1978 and is still being used as rnonitoring point to date. Okeo 2713 Okeo was created in 1982 with its first catch in June the same year. It was used as a regular monitoring point until 1990. 4.1.2.7. Zou Tlre Zou has three catching points, namely. Atcherigbe, Zoudli and Cove. I Atcherigbe 2709 The point was created in 1978 and was under the Sub-sector of Parakou. but transferred to the Bohicon Sub-sector in 1982 after the creation of this Sub-sector. The first catch was made in November 1978 and has since been a regular catching point to date. Cove 3003 Cove was created in 1982 and was under the Bohicon Sub-sector. The first catch was made in August 1982.It was a regular catching point until October 1987 when catches were stopped for the same reasons given under Affon. Zotüi3994 Zoû1i was created in 1982 and was a regular catching point for only two years because of it's low fly count. The hrst catch was made in August 1982; in 1984 catches were drastically reduced. After that year, no catches were made until 1989 when only three months catches were made and one month in 1995. 4.1.2.8. Kouffo The Kouffo has two catching points ;Lanta and Konfokpa. Lanta (code 3001) Catches were made atLanta from 1982 to 1999 Konfopka (code 3008) This point is located upstream of Lanta. Catches were made between 1995 and200l 4.1.3. Entomolosical prospections Several entomological helicopter prospections were carried out on the Oueme and its tributaries for various reasons. Among these were the following: a) Investigations into suspected treatment failure. b) To investigate the problem of re-invasion of the Oueme valley by S. soubrense Beffa form. from neighbouring Nigerian rivers. c) For, purely research reasons d) For. Operational reasons 4.2. History on larviciding 10 4.2.1. Aerial larvicidins Aerial larviciding began in the Oueme basin in week 12, 1987. This continued until week 18, then treatment was suspended due to lack of flow. Vectobac* (8.r. H-14) was the larvicide used. Treatment was resumed in weeli 36 and continued for six cycles, namely, from week 36 to week 41. The larvicide used this time was temephos (Abate@). It is interesting to mention that, only 13 treatment cycles had been carried out in 1987. In fact the "attack phase" of larviciding in the Oueme basin started in 1988 on week 9 with B.t. H-14; (table 1). The larviciding cycles of 1987 can be considered as treatment trials. It is important to note that the period of commencement of treatment was in the dry season. The aim of this was to eliminate the S. damnosum s.1. population at their dry season foci before the onset of the rainy season. In so doing, economy could be made in the rainy season by treating shorter stretches of the river or suspend treatment in view of good results, namely, absence of flies. This theory was however, dashed because of invasion or contamination of the Oueme basin by S. soubrense Beffa form from neighbouring rivers in Nigeria. Since the "attack phase" in 1988, aerial operations have continued uninterrupted in the Oueme basin to date. Aerial operations are suspended only in the dry season when the entire basin dries up (see section 2 paragraph 7 of this report). The period for a minirnum treatment in the Oueme basin for a given year is between weeks I to8 The period lbr a maximum treatment is between weeks 26 to 45, with the peak, occurring between, weeks 36 to 40. These treatment cycles correspond to the pattem of discharge of the Oueme and it's tributaries during a given year as already mentioned. The treatment cycles of the Oueme basin including the Okpara, the Zou and the Kouffo from 1987 to 2001 are in the annex of this report (tables 7.2, 3, 4. 4a, 4b and 4c). 4.2.2. Ground larvrcldrug Ground larviciding is not used in the Oueme basin as the main method of vector control but as support to aerial larviciding in the case of treatment failure due to bad passage of larvicides or when a breeding site is missed after the passage of an aircraft. It is also used in the dry season on certain isolated breeding points to minimise treatment cost of aerial larviciding. At very low discharge in the dry season when aerial larviciding is difficult to carry out, ground larviciding is again ernployed. This is usually between weeks 1 to week 8 on the tributaries -"ir ' 11 Ground larviciding is carried out by the various Sub-sectors of ex Parakou Sector. depending on the location of the points to be treated. 4.2.3. Insecticides used (insecticides rotation) From 1987 to date all the insecticides employed by the Programme (Abaten', B.t. H-14, both Vectobac* and Teknarc', phoxim, chlorphoxim, pyraclofos, permethrin, carbosulfan and etofenprox) are being used on rotational basis in the Oueme basin. The reasons for the rotation of insecticides are as follows 1. To prevent the occurrence of resistance, which may occur if only one insecticide is used, as occurred with Abatee in the early stages of the Programme. In order to avoid this, the consecutive use of insecticides belonging to the same chemical compound is discouraged to prevent cross-resistance. 2. The rotation is also carried out for the cost-effectiveness of treatment. Using B.t. H-14 at very high discharge will require a huge volume of insecticide. This will mean a requirement of a lot of fèrry time for an aircraft and loading. On the other hand an insecticide like permethrin which is highly toxic requires very small volume at very high discharge. thus a small amount can cover a lot of river stretch to be treated. 3. Rotation of insecticide is carried out according to the toxicity of the insecticide at different discharges on non-target organisms. For example B.t. H-I4 which has a very low toxicity on non- target organisms is used at low discharges, namely from I cubic metre per second to about 35 cubic metres per second. While permethrin and carbosulfan, which are highly toxic, are only used when the discharge is higher than 70 cubic metres per second and cannot be used for more than six treatment cycles in a given year. Pyraclofos is used at a discharge of 15 cubic metres per second onwards, and this applies to etofenprox also. On the other hand, insecticides like Abate@, phoxim. and chlorphoxim, which have relatively low toxicity. can be used even at low discharge. 4. Finally rotation is carried out according to the carry of the insecticide. B.t. H-14, for example, which has very low carry, will require a lot of treatment point at higher discharges. This therefore renders it unsuitable for high discharge treatment because the volume of product to be used will not be cost effective as pointed out earlier on. However an insecticide like Abate@, which has a very good carry coupled with its low toxicity on non-target organislns can be used at almost any discharge. Pyraclofos is another insecticide, which has a very good carry but because of its toxicity as indicated earlier on, it is used from 15 cubic metres per second upwards. The practical aspect of the rotation of insecticides can be seen on the tables of treatment of the Oueme basin in the annex of this report (tables I to 4,4a and 4b). In the Oueme basin, resistance to temephos had been intermediary in 1981, but in 1993, resistance was detected at the Lower Oueme area around Agonlin Kpahou (OU 700), Atchakpa (OU 600). the Upper Oueme around Affon (OUl04), and the Upper Okpara around Bassa (OU 710 and OU 720). The susceptibility to temephos became normal in 1998. See graph on "Resistance to temephos Zone East" (fig. 9). 4.3. Entomolosical results 12 4.3.1. The vectors involved To determine the vectors involved in the Ouerne basin, adult flies are caught by vector collectors as described by Walsh er al. (1978) and are separated into different groups, through their wing tuft examination using Kurtak et al. (1981) method. These groups are classif,ted as 01, 02.03, 04. and 05. The 01 groups are the ones where all the individual hairs of the wing tuft are pale. The 02 groups are the ones with the majority of individual hairs of the wing tuft pale, with the presence of some few dark hairs (less than 50% of the total numbers of the wing tuft hairs). These two groups are considered to belong to the savannah group of species, namely, S. damnosum s.s. and S. sirbanum. The 03 groups are the ones in which 50o are pale hairs and 50o are dark hairs. These can be savamrah species (S. damnosum s.s) or S. squamosum or can even be S. soubrense. These are however rare in the Oueme basin. The 04 groups are those in which the majority of the hairs on the wing tuft are dark. The 05 groups are those with 100% dark wing tuft hairs. These two groups are the forest species, S. sanctipauli or S. soubrense falthough it has been pointed out that some members of adult flies rnorphologically looking S. soubrense Beffa form have pale wing tufts (Garms 1978 and Meredith er al 1983.). these have disappeared after the 1983 drought ( Cheke et al 1987)1. From available data for both adult population and larval population, the dominant species on the tributaries of the Oueme is S. damnosum s.s. On the other hand, on the Oueme South of Beterou catching point the dominant species during the major part of the rainy season is S. soubrense Beffa form. See graphs on MBR (Monthly Biting Rate) on seasonal variation of S. soubrense Beffa form at Atchakpa, M'Betekoukou and Aguigadji catching points. These two graphs are obtained from data from 1980 to 2001 (fig. 13, 14, and 15). No S. sanctipauli and S. )rahense have ever been found in the Oueme basin, either by cytotaxonomy or by adult morphological examinations (table 5). 4.3.2. The parasite involved Since the creation of the molecular biology laboratory. it has been shown that the majority of the parasites transmitted in the Oueme basin are the Savannah strains. Occasionally some forest strains are also transmitted. It is important to note that these Savannah strains are transmitted by both the Savannah flies (S. damnosum s.s. and S. sirbanum). and the forest flies, namely, (S. soubrense Beffa form) (table 6). 4.3.3. Transmission From the tables of the Annual Transmission Potential (ATP) and the graphs of ATP for both the Oueme and it's tributaries. the pre-control data showed that transmission was very high on both the Oueme as well as it's tributaries. The ATP values for all species combined were over 6000 at M'Betekoukou (Oueme), and Atcherigbe (Zou). On the Okpara at Kaboua, the ATP was slightly over 8000 (tables 7 ,7a and 7b). The other points like Atchakpa, Beterou and Aguigadji on the Oueme had pre-control ATP of less than 4000. 13 On the other points of the tributaries, like Wari Maro (Terou), and Vossa (Beffa) the pre- control ATP was around 5000. Tlre rest of the points like Banon (Adjiro), Zagnanado (Oueme), Affon (Oueme), and Barerou (Yerou Maro) had pre-control ATP of less than 1000. Before vector control operations started, there was a severe drought in 1983, and the situation returned to normal after 1985. This drought affected both the pre-control ATP and ABR significantly, as shown on the graphs of ATPs and ABRs (fig. 10, 11,12, and l2a). The transmission during the larviciding period is from 1988 to 2001. The drought mentioned above greatly helped to bring down transmission from pre-control data to around an ATP of about 1000 as early as 1986. a year before aerial larviciding. The only point which had ATP of more than 1000 was M'Betekoukou, with ATP of more than 2000 in 1992. In 1994, after seven years of larviciding, the ATPs on all the points in the Oueme basin, except at Kaboua on the Okpara, had fallen below 1000. These results are exceptionally good, considering the time involved. It is however important to note that apart from the drought factor, large-scale ivermectin distribution began in the Oueme basin in 1989. On the Oueme itself greater proportion of transmission is by S. soubrense Beffa form, as shown by histograms of ATPs at the following catching points, M'Betekoukou, Aguigadji, and Atchakpa. However, on the Upper Oueme at Beterou transmission is mainly by Savannah species S. damnosum s.s and S. sirbanum (fig. 13 to 16). On the northern tributaries like the Terou and Yerou Maro, again S. damnosum s.s. and S. sirbanum are the major transmitters; ATP histograms of Wari Maro and Barerou catching points show tlris clearly (frg.2l and22). As one goes down south, transmission by S. soubrense Beffa form becomes important on the tributaries like Beffa, Okpara, and the Zou (fig. I 8, l9 and 20). 4.3.4. Special studies qn§. soubrenseBef for Special studies on the seasonal variation of S. soubrense Beffa form had been carried out in tlre rainy season on the Oueme river and its tributaries in 1991 and 1992. These studies had shown that the M'Betecoucou area was very highly contaminated. A very important contamination was also observed around Kaboua on the Okpara river. Farther from the 'West Nigerian border towards and North, less or no contamination had been observed (frg. 23.24 and ?5\ 4.3.5. Entomological Results on 3l Décembre 2001. In the Ouérné basin, out of a total of 15 catching points regularly monitored in 2001, three (3) showed a corrected ATP O. volvulus above 100. These points are M'Bétékoukou with ATP :294:. Kaboua with ATP :210 and Djabata with ATP : 261. All these points are located near the nigerian border and are regularly re-invaded in the rainy season by S.soubrense Beffa form. Considering the transmission by the savanna species of similium, only the catching point of Diabata (on the Okpara river) showed an ATP above 100 which was 138. Given the very high precontrol data (ATP above 2,000 at most catching points and 6.000 # 8.000 at M'Bétékoukou and Kaboua) it can be said that the entomological situation is relatively good in tlre Oueme basin (tabl es J , 7 a,7b, et frg. 26 to 3 5). 5. SURVEILLANCE OF AQUATIC FAUNA The chemical insecticides used by OCP are degradable and do not accumulate in the food chain. The doses used to kill simulium larvae are not toxic for humans and mammals. This is OCP first requirement in the choice of anti-simulium larvicides. Insecticides that meet these requirements are submitted to the screening procedure established by OCP Programme and its Ecological Group. This independant Ecological Group which includes international Experts scientists analyzes the results to provide guidance to OCP monitoring and aquatic environment protection action. National teams of hydrobiologists are in charge of the surveillance of aquatic fauna (invertebrates and fish). See figure 36 for the location of aquatic fauna surveillance sites. Most hydrobiological surveillance stations in Benin are located on the Ouémé river near Zagnanado, M'Bétékoukou, Atchakpa and Bétérou. The stations on the tributaries are; Atchérigbé on the Zoq Kaboua on the Okpara, Vossa on the Beffa and Lanta on the Kouffo. The Bénin national hydrobiologists team, had undertaken monitoring at these sites from 1981 to 1987. In 1987, monitoring was suspended following the reduction of the surveillance stations by the Ecological Group and the financial difficulties of the Programme. In 1995, OCP consultants did some samplings at M'Bétékoukou and Bétérou. Regarding the ichtyofauna, the two stations regularly monitored were M'Bétékoukou and Bétérou on the Ouémé river. Total weight of CEU showed an increasing trend fi'om 1981 to 1986 for the Bétérou station and frorn 1982 to 1986 for the M'Bétékoukou station. This increase in catches was confirmed by the ponctual catches carried out in 1995 at both stations. The specific abundance noted in 13 fishing sessions showed 41 species at Bétérou and 55 species at M'Bétékoukou in 16 samplings. The fish inventory carried out in 1995 did not show the disappearance of any fish species because of larviciding. However, it should be noted that some cases of fish mortality related to the use of ichtyotoxic chemicals in low waters were reported several times in the Ouémé basin. Regular surveillance of aquatic entomofauna was not organized due to unfavorable hydrological conditions. Ponctual samplings carried out at Atchakpa and M'Bétékoukou do not allow to draw any conclusion concerning the impact of larvicides on the fauna at these two stations which showed poor taxonomic abundance of saxicole fauna. At Bétérou, the taxonomic abundance of saxicole fauna is more important than in the two other stations. On the contrary, the density of fauna observed in 1995 is lower compared to densities recorded in 1985 and 1986. On the whole, as the period of surveillance of aquatic fauna on Ouémé was short, it was not possible to detect any effect of larviciding on the fauna in this river. But from observations carried out on other rivers treated with the same larvicides it can be envisaged that there is no impact on non- target aquatic fauna. 15 6. EPIDEMIOLOGICAL EVALUATIONS 6.1. Erridemiological results before vector control. The surnmary of the epidemiological data, for the Oueme basin, can be found in the annex of tlris report (tables 8. 9, 10 and figures 37 to 4l). 6.1.1. Oueme The pre-control data for the epidemiological survey showed villages with very high prevalence. The notable ones are villages on the Oueme itself, south of Beterou catching point. The Community Microfilarial Load (CMFL) was also quite high in these villages, e.g., l. A village like Abgagoule. code 3g2,hadprevalence of 70.20 in March 1979 (8 years before vector control), with CMFL of 16.74 mf/s, and prevalence blind of 0.6%' 2. Agonlin Kpahou, code 5078, had prevalence of 72.2% in December 1989 (barely 2 yearc after aerial larviciding), with CMFL of 13.91 mf/s. no blind case recorded. 3. Atchakpa, code 3881, had prevalence of 68.2Yo in May 1978 (9 years before aerial larviciding). with CMFL of 23.51 mf/s and prevalence blind of 3.5Yo. 4 M'Betekoukou, code 399, had prevalence of 78.00 in April 1979 (8 years before aerial larviciding), CMFL of 19.59 mf/s, and prevalence blind of 1.7%. 5 Koko. code 205, had prevalence of 64.4% in May 1978 (9 years before aerial larviciding), with CMFL of 36.79 mf/s. and prevalence blind of 2.3oÂ. 6 Idadjo. code 390, had prevalence of 73.4 % in March l9l9 (8 years before aerial larviciding), with CMFL of 28.89 mf/s. and prevalence blind of 1.3%. 7 Banicri, code 315, had prevalence of 69.3% in June 1977 (10 years before aerial larviciding), with CMFL of 24.80 mfls, and prevalence blind of 0.3%. 8 Aguigadji, code 408/5083, had prevalence of 8l.9yo in April 1979 (8 years before aerial larviciding). with CMFL of 33.31 mf/s, and prevalence blind of 3.7Yo. 9 Wewe, code 316, had prevalence of 61.90 in June 1977 (I0 years before aerial larviciding), with CMFL of 12.72 mf/s, and prevalence blind of 0.3%. 6.1.2. Zou In the Zou valley, epidemiological surveys had been carried out at least once in 14 villages. Out of these, four villages will be used for this report. These four villages are chosen because of their high pre-control prevalence. 1. Ferme Agbodjime, code 5076, had prevalence of 68.8% in December 1989 (barely 2years after aerial larviciding). with CMFL of 17.49 mf/s. with no record on blind case. 2 Konkondji. code 395, had prevalence of 72.4o in March 1979 (8 years before aerial larviciding), with CMFL of 24.56 mf/s, and prevalence blind of 2.3oÂ. 16 J Zonto, code 400, had prevalence of 695% in April 1979 (S years before aerial larviciding). witlr CMFL of 25.82 mf/s and prevalence blind of 3.5%. 4 Avideme. code 5249, had prevalence of 66.4% in October 1990 (barely 3 years after aerial larviciding), with CMFL of 20.16 mf/s. No blind case recorded. 6.1.3. Terou 01 the Terou-Oueme basin. surveys had been carried out at least once in seven villages. The pre-control prevalence for these seven villages has a range of 59.7oÂto 82.6%o. Except for two of these villages, namely, Igbomakoro, code 386, and Sawoundi, code 387, the rest had been visited only once. These villages therefore will be used for illustrative puposes. I Igbomakoro had prevalence of 78.40 when it was first visited in May 1978 (9 years before aerial larviciding), with CMFL of 31.89 mf/s, and prevalence blind of 0.7%. 2. Sawoundi had prevalence of 59.7% in May 1978 (9 years before aerial larviciding), with CMFL of 14.72, and prevalence blind of 0.60Â. 6.L.4. Kouffo Pre-control epidemiological surveys had been carried out in eight villages in the Kouffo valley. The pre-control prevalence was not very high cornpared to that of the Oueme or the Terou. Except for the village Kogbetohoue, code 401, where the pre-control prevalence was 60.4oÂ. in April 1979, the rest of the villages had prevalence of less than 50oÂ. The range is 6.7Yo to 46.50Â; (table 8). 6.1.5 Oknara For pre-control data of epidemiological surveys two villages are chosen for illustrative prlrposes, and these are: Kaboua, code 275, had prevalence of 69.6% in May 1978 (9 years before aerial larviciding), CMFL of 17 .52 mf/s and a prevalence blind of 0.3oÂ. 2 Woria, code 396, had prevalence of 70.4% in April 1979 (8 years before aerial larviciding), with CMFL of 23.91 mf/s, and prevalence blind of I .5%. 6.2. Epidemiolosical results durins Vector control. It is irnportant to mention that the good epidemiological results on the Oueme river and its tributaries are due to both vector control and ivermectin distribution. The following villages illustrate these results As already shown the pre-control prevalence for M'Betekoukou was 78.0% with CMFL of 19.59 mf/s (in 1979). In February 1987, the prevalence was unchanged (78.8%). In 1994 during the month of December the prevalence fell as low as 18.1% with CMFL of 0.41 mf/s. 2 Zoudji, code 5396, had a prevalence of 46.40 in December 1992, with CMFL of 4.75 mfls. In November 1995, the prevalence fell to 14.60 with CMFL of only 0.44 mfls. 17 J Fonkpodji, code 394,had prevalence of 63.10 in March 1979, with CMFL of 17.45 mfls. Two years after ivermectin distribution, namely in7992, and barely five years after vector control started, the prevalence fell to 50.8%, with CMFL o18.92 mf/s, and three years later, namely, in 1995, the prevalence fell to 22.6% with CMFL of only 0.88 mf/s. 6.3. Latest losical results 6.3.1. Oueme On the Oueme itself, the latest epidemiological evaluations had been carried out in the following villages. 1. Atchakpa. code 381/5880, which had pre-control prevalence of l2.2yo, as already mentioned, now has prevalence of 3.8o in April 1999, with CMFL of only 0.13 mf/s. 2. Idadjo, in February 1998 has prevalence of 17.7oÂ. with CMFL of only 0.55 mfls, compared to 73.4%o as already mentioned. 3. Koko, in February 1998 has prevalence of 9.8Y" compared to 64.40 in May 1978. 4. Tosso. in April 1999, has prevalence of 5.4o compared to 57.3o in October 1989. 5. Wewe, in April 1999. has prevalence of only 0.6% compared to 619% in J:une 7977 . 6.3.2. Tributaries of the Oueme Latest results of the villages on the tributaries of the Oueme, like, Okpara, Zott, Terou and the Kouffo. showed that the prevalence has fallen so low. In some areas it is less than l0oÂ, with CMFL of less than I rnf/s. (tables 8, 9, 10 and fig. 38 to 41). 1. Konkondji; code 395; in March 2000 had a prevalence of 1 .9o and a CMFL of 0.08 mf/s compared to 72.40 of prevalence in March 1979. 2. Wokpa; code 5038. in December 2000 had a prevalence of 0.8% with a CMFL of 0.01 mf/s. compared to 54.8% of prevalence in October 1989 with a CMFL of 7.89 mfls. 3. Zouto: code 400, in December 2001, had a prevalence of 1 .8% and a CMFL of 0.06 mf/s. compared to 69.5Yo of prevalence in 1979 as already mentioned. 6.3.3. Kouffo 1. Lanta; code423 inApril 1999,hadaprevalenceof 0.60 withCMFLof 0.02mfls compared to 42.70 of prevalence in Mai 1979 wrth CMFL of Smf/s. 2. Kogbetohoué; code 401; in february 1998. had a prevalence of 13.6%o with a CMFL of 0.47nfls. compared to 60.4o of prevalence with a CMFL of 13.97mfls. and 1.26% of blindness in April 1979. (fre.42). 6.4. Recentophtalmologicalevaluation. In December 2001, an ophthalmological evaluation was carried out in 06 villages in the Oueme basin in Benin. 18 Out of a total population of 1987 people, 1365 were present. Skin snip was made on 1362 people and 1105 people aged 05 years and above underwent ophthalmological tests. This test concerned the anterior and posterior segments of the eye. Results analysis showed that skin and eye parasitisms had strongly reduced both in terms of rnicrofilariae load and number of cases. Indeed, the highest microfilariae loads were 377 at Zouto in 1987;66 at Okpa and 64 at Madengbé in 1995 compared to 22 at Okpa and I 1 at Madengbé in 2001. Concerning the eye lesions, the microhlariae loads were 63 at Zouto in 1987; 19 at Madengbé andT at Okpa in 1995 against 4 at Okpa in 2001. A clear regression in cases of serious onchocerca eye lesions was noticed. All inflamatory lesions had regressed except two cases at Okpa. The highest microfilariae loads were recorded in this village (tables l1 and 12). Indeed, the village of Okpa is located at the confluence of Oueme and Okpara rivers close to the border between Nigeria and Benin. It is known that the medium Ouémé and Okpara are re-invaded in the rainy season by S. soubrense Beffa form coming from Nigeria. In conclusion, the ophtalmological survey carried out in December 2001 revealed that there was a clear regression of eye onchocerciasis in the 06 villages surveyed. 7. IVERMECTINDISTRIBUTION Large-scale ivermectin distribution began in the Oueme basin and the Kouffo in 1989. Nine villages were covered. In 1 990 in Zone 3, eleven ( 1 1 ) villages were covered In 1991 the Oueme area was again visited, this tirne covering 36 villages in Zone 3 In 1992 the Lower and the Upper Okpara, as well as the Middle Oueme were visited, covering again 36 villages. also on the Agbado, the middle Zot(Zote 4), where 104 villages were covered. In 1993 the areas, where large-scale ivermectin distribution took place were Kouffo, Oueme and Okpara, where 415 villages were covered. In the same year (1993) the Oueme and the Zou were visited. covering 347 vlllages. and on the Kouffo 187 villages were covered. ht 1994 the Agbado, the Middle Zou had large-scale ivermectin distribution which covered 14 villages; (Zone 4). In 1995, Zones 3 and 4 were visited again covering 349 vlllages. In the same year, the Upper and the Middle Okpara (Zone 5) were visited, where 312 vrllages were covered. In the same year, Terou (Zone 6) was also visited covering 305 villages. It should be noted here that, from 1990 to end of 1996, the national mobile teams. headed by the national Co-ordinator carried out large-scale ivermectin distributions, involving the local district health units. The details of ivermectin distribution. from 1989 to 2001. can be found in table 13 in the annex of this report. 19 In January 1997, the village communities were trained to carry out large-scale ivermectin distribution themselves, this had therefore been the case since then. 8. SOCIOLOGICAL INVESTIGATIONS. At the time of writing, no sociological investigation had been carried out in the Oueme basin. 9. POPULATIONS SENSITIZATION AND MOBILIZATION ACTIVITIES It is irnportant to recall that since 1974, OCP Programme management have constantly expressed the need to get various community social elements involved in sensitization and mobilization activities whenever this was feasable. As from 1975 an information campaign through the media and health education services was launched to sensitize people about the dangers relating to onchocerciasis. Advertisement on posters and in the rnedia was used. The communities were rapidly able to understand the relationship between the black flies and blindness as well as the objectives of the programme. They understood the weekly intervention of airplanes and helicopters that carried out aerial larviciding. The efforts to provide information did not target populations at risk only. They also targeted administrative and health authorities to ensure their full adherence. They also targeted donors countries which were concerned with the monitoring of an action they were supporting. Population sensitization and mobilization activities are ensured by VCU teams during entomological prospections, and by national teams before epidemiological evaluations and ivermectin distribution. All the social segments as well as the political and administrative authorities in the areas visited by the teams were targeted by the sensitization (teachers, traditional healers, health agents and religious leaders, etc.). Talks were organized and leaflets on OCP activities were distributed in the villages; and films were shown anytime that was possible. The following themes were discussed during the talks * Onchocerciasis transmission; relation between the river. the bites of the black flies and the disease *The clinical signs of the disease: itching, acute skin lesions (onchocerciasis dermatitis), nodules, chronic cutaneous symptoms (depigmentation), dimsight (progressive visual impairment, blindness). * The socio-economic consequences; disabilities (blindness), abandonment of first line villages (closest to the river) and most fertile valleys, which is an obstacle to socio- economic development. * The control of the disease, vector control, ground larviciding, chemiotherapy (treatment with ivermectin). 20 Regarding vector control, the involvement of the populations is requested to look after kerosene and insecticde stocks to prevent theft. Concerning ivermectin treatment, a particular emphasis is laid on the doses to administer depending on patients' size, contra-indications, periodicity, drug intake regularity, side effects and appropriate behavior. The progressive intensification of sensitization resulted in the gradual increase in the coverage of ivermectin distribution. It also resulted in the easier acceptance of skin snip during epidemiological surveys. As far as vector control is concerned, the sensitization of populations led to a significant reduction of cases of theft of kerosene and insecticides in the depots in the field. 10. DISCUSSIONS. I 0.1 . Fly catching data from 1980 to 2001 showed a particular pattern of seasonal variation in fly snecies oooulation. The seasonal variation is between S. datnnosuln s.s and S. sirbanum on one hand and S. soubrense Beffa form on the other. From the analysis of data from 1980 to 2001, it is clearly shown that S. soubrense Beffa form becomes the major component of the fly population in the Oueme basin during the rainy season and completely absent during the dry season. This is true only at the stronghold of S. soubrense Beffa form areas (the Oueme valley from Atchakpa to Aguigadji, and on the Okpara from Kaboua to the confluence with the Oueme). See radar graphs on seasonal variation of S. soubrense Beffa form at Atchakpa and M'Betekoukou (frg.24 and 25). 10.2. From 1988 the first year of the "attack phase" of aerial larviciding to date, vector control operations have produced very good results, as can be seen in the various ATP graphs in the annex of this report; (fig. l2 and 13). In some places the ATP had rapidly fallen to very low levels. The ATP of less than 100 is recorded in some places. after only 9 years of aerial larviciding. The drop in ATPs in the Oueme basin is very rapid compared to what normally occurs during vector control. This rapid drop in ATPs can be attributed to three factors: i.) the first factor, being the severe drought, which occurred in the sub-region in 1983. From the graphs of ATPs on the Oueme and the tributaries, it is shown that after the drought, and even four years before aerial larviciding, the ATPs had started dropping already. These ATPs did not come up to their original values after the end of the drought, which was marked with the beginning of the 1985 rainy season. In fact. the ATPs remained low till the beginning of aerial larviciding in 1988. ii.) The second factor being, the beginning of large-scale ivermectin distribution in the Oueme basin in 1989. It has been shown that the intake of ivermectin by the human population in an area can reduce the rnean microfilariae load (mf1 in the skin of treated person by 96%, - 99%. After 12 months, tl-re subsequent mf-repopulation in the skin is about 40o of its original level (Remme J. et al 1990). The reduction of microfilariae load in the human population therefore results in the reduction of infective larvae in the fly's head (L3H). The ATP calculation is based on the presence of infective larvae (L3H) in the head of the fly. The ATP will theretbre be low if few L3Hs are obtained. iii.) The third factor is vector control itself. From the graph of the Annual Biting Rate (ABR). it can be seen that. although the basin is contaminated each year by S. soubrense Beffa form flies from Nigeria, there is progressive downward trend. This means, there is gradual reduction in fly population each year. indicating good control strategy (fig. 10 and 1 1 ). 21 10.3 It is irnportant also to comment on the vectorial role of the S. soubrense Beffa form in the Oueme bassin. As already mentioned earlier on in this report, S. soubrense Beffa form is the major transmitter i1 the Oueme valley itself. Transmission by S. soubrense Beffa form is in the rainy season only ( fig. 24 and 25). There is no transmission in the dry seasou as it is in the case of S. squamosum in perennial rivers (Cheke et al 1991). On the other hand. it has been shown that S. yahense does not sliow any major seasonal variation in transmission (Cheke el ul 1992). This therefore, means that if S. soubrense Beffa form were not to be a contaminant of the Oueme. the ATPs would have been lower tlran what they actually are. This can be seen in the parts of the basin, which are not the strongholds of S. soubrense Beffa form (frg.23) If one compares the ATPs from the Beffa strongholds with the ATPs from other parts of the basin. it can be seen that, the values of ATPs in the strongholds are 3 to 4 times higher. 10.4. It is important to note that S. soubrense Beffa form spreads very little from their points of arrival in the Oueme basin, namely, the Lower Okpara and the Lower Oueme (their strongholds). They are therefore rarely found to the west or to the north of the strongholds. Although it has been shown in the laboratory that S. soubrense Beffa form can fly long distances (Cooter 1983), they seem to restrict themselves to the strongholds in the Oueme basin ( frg.23)- 10.5. The pre-control epidemiological data showed high prevalence values for the Oueme basin, around the strongholds for S. soubrense Beffa form (68% - 80%). On the other hand prevalence blind values for the same areas were quite low (1 .70% - 3.5%). This shows that, although S. soubrense Beffa form, are good transmitters of the Savannah strain of the Onchocerca parasite (DNA lab results), the transmission does not result in the blinding type of Onchocerciasis. This situation is worth looking into for clarification. The question to be answered is this. "Is the Savannah strain of Onchocerca parasite transmitted by S. soubrense Beffa form different from other blinding Savannah strains found elsewhere?" 11. CONCLUSION. The latest entornological and the epidemiological results show that the onchocerciasis situation in the Oueme basin is good. There is progressive regression of onchocerciasis by way of transmission by the fly (ATPs) and the prevalence in the human population. This means the control strategy in use (cornbination of vector control and ivermectin distribution) is a good one. Especially, if one takes into consideration the duration of vector control in the Oueme basin. The composition of the fly population in the Oueme valley varies according to the season. In the rainy season, S. soubrense Beffa form constitute the majority of the fly population on the Oueme itself. In the dry season and late rainy season the population composition changes to S. damnosum s.s and S. sirbanum. The data available show that S. soubrense Beffa form is a good and important transmitter during the rainy season, but not a good transmitter if present in the dry season. This means that if there was no contamination phenomenon by S. soubrense Beffa form, the onchocerciasis situation in the Oueme basin would have been better. 22 ACKNOWLEDGEMENTS Our sincere thanks go to the Programme Director of OCP and the Chief of Vector Control Unit (VCU) for giving us the singular honour by inviting us to come to Ouagadougou to write this report. The writing of this report would not have been possible without the help of all the VCU staff in both Ouagadougou and in the field. This is to say a big thank you to them all. Our special thanks go to Mr. Aké Flavien, Mr. Pierre Nikiéma and Robert Toé for the vital tips provided in the use of the computer in the writing of this report, in the making of the various graphs and the maps of this report. Many thanks to Mr S. N'Gadjaga and Mr. D. Somé for all the computer installations which made it easier to write this report. We would also like to express our sincere gratitude to the PET Unit for the epidemiological infbrmation provided as well as the data on the large-scale ivermectin distribution in the Oueme basin. 23 REFERENCES Agoua. H., Quillévéré. D., Back, C., Poudiougo, P., Guillet, P., Zerbo, D.G., Henderickx, J.E.E., Sékétéli, A. et Sowah, S. (1991). Evaluation des moyens de lutte contre les simulies dans le cadre du Programme OCP (Onchocerciasis Control Programme). Ann. Soc. Belg. Méd. Trop., 199I, 71 (Suppl. r).49-63. Agoua, H., Alley, E.S., Hougard, J.M., Akpoboua, K.L.B., Boatin, B. et Sékétéli, A. (1995). Etudes entomologiques de post-traitement dans le Programme de lutte contre I'onchocercose en Afrique de I'Ouest. (Parasite, 1995, 2,281-288). Anonyme (1985). Dix années de lutte contre l'onchocercose en Afrique de l'Ouest. Bilan des activités du Programme de lutte contre l'onchocercose dans la région du bassin de la Volta de 1974 à r984. OCP/GVA/85. 1A. Anonyme (1995). Vingt années de lutte contre I'onchocercose en Afrique de I'Ouest. Bilan des activités du Programme de lutte contre I'Onchocercose en Afrique de I'Ouest de 1974 à 1994. Banla M., (2001). Rapport d'une mission d'évaluation ophtalmologique au Bénin §ovembre Décembre 2001). Document PET / OCP. Cheke R. A., Garms R.. Ouedraogo J., Some A., Sowah S., (1978). The Beffa form of Sirnulium soubrense of S. damnosum complex in Togo and Benin. Medical and Veterinary Entomology (1987) l. 29-35. Cheke R. A., Sowah S.. Avissey H. S. K., Fiasorgbor G. K., and Garms R. (1991) Seasonal variation in Onchocerciasis transmission by S. squamosum at perennial breeding sites in Togo. Transactions of the Royal Society of Tropical Medicine and Hygiene (1991) 85. Cheke R. A., Avissey H. S. K., Sowah S., Walsh J. F.. and Garms R. The vectorial efficiency of Simulium yahense populations in South-Eastern Ghana. (In press). Cooter R. J. (1983). Studies on the flight of the black flies (Diptera: Simuliidae). II. Flight perfbrmance of three cytospecies in the complex of Simulium damnosum. Theobald Bulletin of Entomological Research. 73. 27 5 -288. Garms R. (1978). Use of morphological characters in the study of Simulium damnosum s.1. population in West Africa. Tropenmedizinand Parasitology (1978) 29.483-491. Garms R., Cheke R. A.. Vajime C. G., and Sowah S. (1982). The occurrence and movement of different rnenrbers of Simulium damnosum complex in Togo and Benin. Z. angew Zool (1982). 69. 219-236. Garms R., Cheke R. A. (1985). Infection with Onchocerca volvulus in different members of the Simulium damnosum complex in Togo and Benin. Z. angew Zool (1985) 72. 479-495. 24 Guillet P., Escaffre H., Ouédraogo M., Quillévéré D., (1980). Mise en évidence d'une résistance au téméphos dans le complexe Simuliunt damnosum (5. sanctipauli et S. soubrense) en Côte d'Ivote (Zone du Programme de lutte contre I'Onchocercose dans la région du Bassin de la Volta). Cah. O.R.S.T.O.M., série Ento. Med. et Parasitol., vol. XVIII, N'3, 1980:29I-299. Hougard, J.M., Poudiougou, P.,Zerbo, D.G., Meyer, R., Guillet, P., Agoua, H., Sékétéli, A., Alipoboua. A., Sowah, S., Samba, E,.M., et Quillévéré, D.. (1994). La lutte contre les vecteurs de l'onchocercose en Afrique de I'Ouest; description d'une logistique appropriée à un programme de santé publique de grande envergure. Cahiers Santé,4, 389-398. Kurtak, D. C.. Raybould. J. H., and Vajime, C. (1981). Wing tuft colors in the progeny of single individuals of Simulium damnosum (Enderlein). Trans. Roy. Soc. Trop. med. Hyg., 75. 126. Meredith S. E. O., Cheke R. A., and Garms R. (1983). Variation and distribution of forms of Simulium soubrense and Simulium sanctipauli in West Africa. Annals of Tropical Medicine and Parasitology (1 983) 77 . 627 -640. Remme J., Desole G.. Dadzie K.Y., Alley E. S., Baker R. H., Habbema J. D., Plaisier A. P., and van Oortimarssen G. J. (1990). Large-scale ivermectin distribution and its epidemiological consequences. (Review) Acta Leidensia. 599I-2): ll7 -91, 1990. Sowah S. A., Kassambarâ M., Avissey H. K. S.. Amadou A., and Gbaguidi P. (1992). Seasonal Variation of S. soubrense Beffa form population in the Oueme valley and its vectorial eff,rciency in 1991 and 1992. (Unpublished). Vaiime C.. and Quillevere (1978). The distribution of the Simulium damnosum complex in West Africa with particular reference to the Onchocerciasis Control Programme area. Tropenmedizin and Parasitology (l 978) 29. 473-482). 25 ANNEXES I î @ - r\ z c (1 ro ao q l- +r a l.ac.a.a.a. T E a o c q3 o € o o f. 98E8àR m- 3 3 3 3 3 o o e. o d =ô====rEoooo o o o 4l;3È! m \ - SL *rP-oi z aÈqE9+ o o o o :: d JË O d o D oa.c EË iEnq,ô! a o =3Ëoos ( î'I e 6'8 ô o t2. d !rô 9 üe.dô o ioo aof-a o ,--oN= D z' o Fd o o s 1. Ë-Pââ 3 I diüo 9. o 0o o ô 0. + f g o FI o a o @ m /" LJ,\. t I \\ o 3 m o o oI o \ oô = -,AÈn | -+,'\ .' o{ o f o o 6 zo o q\;rr oz r ù 9o àrn È ç*f8Ë h a=>(J =rn cna Ii8ï 6r frifr I U, ou, (ô e m = I ï I o È[e o .l m V- o @ ol. >rn à + zt ËÉ =o rô t-8à= b tr, -9 -n= '->-{ ômo 3 rnï tri eI o F{ F. DISCHARGES 0q J J Fl N) § O) @ o N) o o o o o o o t§ oz o o o o o o o oÿ, OS zo 7e zo z0 o È @o €û 7 o É m m @ m ee ax { ez o{ o? tx § r.?2 { vo vê 70 vg (Jr N)l§rrr++t+t oo(o(o(o ro(o@{ N F4 ts. DISCHARGES æ JJN)NO)('§§ n (Jto(Jto(ro(Jto(, o 07 o ooooooooo O^ L' 06. OS o9 7z 7ê 76, 7S zo ?z o cû oU' cû 7 É €2 o m m m @ x ca CN { @ ez m -{ (?d L - vm o (?ô C r?2 { l.?9 ÿz ÿ-(r ÿû 7S 79 ,12 s +*f+1 oo(o(o(oN)N)JJJ oo(o(o(oro(o@! (, DISCHARGES rn I N) (, § (Jl O) ts o o o o o o g 07 o o O o o o o o § oê oa o> o9 z7 7^(r za zS 79 o e7 a eû o 7 eû o É €2 am m m x €e { U' { oz o ûü vm üt o TD m t?2 d9 v7 ÿ^IJ ÿt 7S ÿ0 '12 ..ù ++++t oo(o(o(oN)N)rar § oo(o(o(oro(o@{ DISCHARGES |!n q J J N) N) (j) (, o (n o (, o n o o o o o o o7 o o I oa I I 06. I I o> t I o9 I 7z 7rt r zrl 7S zg g ez a o cL? n €ô o m UI H?2 m { o dep o o oz N (., æ dr? { üt 7m o ü> C ü9 ÿz ÿa ÿo 7S ÿg ,12 q, *+t+t oo(o(o(ol§N)rJr oo(o(o(oJo(o@{ 6 Figure 6 OUEME BASIN BREEDING SITES TOGO NIGERIA t( (Fish traps) 1 go \ LEGENDS \t/rr Breeding sites ,-,.r. Main river Figure 7 7 OUEME BASIN SHOWING CATCHING POINTS o o VILLAGE TOGO NIGERIA Qo*orr" 1 % \ u- LEGEND O Gdching pdnt Figure 8 I MAP SHOWING CODES OF RIVER STRETCHES OF THE OUEME BASIN ou411 ou520 TOGO NIGERIA ( 1 % \ LEGENDS River stretch Main river - E tg T il[tâil5t5ll5t E tatataté t:lH ?rr lâr Ei ,Er|ErrEr|â( -{ EEEE I D ITII TI it' IIIT E tst IIIT fl IIII E IIII E ITII 6 E ITIT Ii E :Y E I Et- I tr I tr I tlII l( I IIII E I IlIl 6 I E I E I II E IT E N II I II N u u E N -l 7 E m x x x E =m x x x z N -t x u E 2o v c) E -{ x (] E - o t9 FI ! tt o x C) ts C ! ! -E '! T il m I NI .E m T t t u ! T T tÂ!It @ -o ! tK .E 2 T T T C) -o T E z T T -E It to tr @ ! T ! ! (-, rc T tf ! tIT f\) ! T -o -E i;t o T u T T T -D a a ! c) T 'o -o v a T T ! c) a a a ! C) () c) N E - 7 v n u r) liil trt 7 v a o l< F ! o c) c) ô E R ÈI fa o E R tii R E E E Iltttr E x x x 7 IlttIl ts rfl ! : E E tsN x x II N x II x E Il N v--{ II x E m x x E m z. x x N { x x E zo x x x x x E -J 6 x x x E m- It o ! x ! 1 C ! T T t m v !9 -D il ! ! -o la! rn @ T T T t !! (n t v n E z t I u T E (o il @ u 7 T ! T : t! T§ ! a x x T T -o ! il o E! o v T il ! x E' .! T T -! T â N n x u x x n x x u x x 7 m r r r x x x x x rrlr ll il 11 11 lt ll lr il ltm aEggiËsâ53 Ë ô-ü g.!_3 < 99 §st+! e:d = ;--l v§§- o (o io rI) (o ro @ @ @ B o æ ! T o o o lllllto o o o o o o o o o o o o o o o o o o Ffl c c C c c c C c c c C C c c c C C C C C c C C c C t! (rt g È co ! o o ol o s ! oi (rl or È N o or (n o (ù o N o o o o o ô N o o o o o o o o o o o o o o -{ @ N o o o o o N o §, o o o o o u ô o ô ô o a U I o E (, IIEIE IIIIETIEIIEIIITIIITI tE IIIIE E IIBIE ER TIEIE E E E HE E I E t-I ! I N I E ttI I E 6I I E I }II I E E HN x N x E x x x N v-J x x x x x qN rTI x x l§ m= x r N z T x x x ! -{ x x r r r m x x IN o T z. r E r T x x N -{ il T r m T m x x x E m- r E r ti o I I C r r r r r t m T E§ T -tr T trlt m il @ r 'o m 't ï x x lt I m r T -E m T t il x x !É z r m r T 1 t x x v x f?I r€) -o i[ .,Jæ r T ï a D - T ! T T T IJ N ! ! 1 E o il o 7 ?c! It F t5 r r 1 ! a It x n x x r m 7 v T r r ! T x 7 x x æ n -o T x T x x n m x m x r m r !ô F r r x x x x h; r m r x It E x x tn x x lù x I8 x o ls IIrt l!" m- IIIIIEETET EIIBIEBIBI IIIIIIIIEIEIIEIBEIEI ltttltlE rllrlltEllt[lrN I -t In --{ m rll= --{ z x -t x -{ -{ -{ zo -l T m m m m o m v C T T m r -{ --{ x x x x x n 7 T m =m ul x x v T r I ! x x x x -o x r r z T T ro @ ! { r T t ! N T T 'o o ! T T r T r T x ! a r T -{ --{ x x -1 F x I I x i + i x x I I I i x --{ I -{ --{ x I --{ x ôq IlIIIIIl m- ËaËg§3{*§53 ô-ü q.E f < gp. erS=!J C:d f r '- W = -i s-lÈ; t§ N tu N N N ]§ o o o o o o (o (o (o (o (o @ (o @ (o (o (o (o (o (o (o ao @ @ (o @ @ (C, ao (o ao ao (o ((, (o @ (o (o «, (C' ço ao @ (o (o @ (o (o (o (ô (o (o II N II (, ll à II Or (t, { @ { II (o v x T§ m II o II x ,§ -t N II N m N z o { I -{ x x x àN o N clr z N + x x x x x x x (D J- x x x x x 1' ! 1' {N m { -{ -.1 x x x x x x x N o @ x x x x x x x x x x 7 o c) o (oN 1' -l { x x x x x x a c) c) o oOJ a x x x a C, ô c) o o o (» a) n n T c) o v o o o o o N n 7 7 x x x ! C, C) (.) c) o c) c) o vm n n v 1' 1' l, x x x 1' 1' 1' 1' ô o C) o c) c) s (oJ 7 A 1' 1' 1' -o C) o n x 7 o c) o c) o (,r @ a a a l, 1' 'o » v a 1' 1' ! T T C) o { o o) I ! 1' -1' ! l, t ! -t t) 7 a 1' ! l, ! 1' ! l, 1' ! T 1' o c, {o oN l, 1l T 1l 1' l, 7 a a l, t 1' ! ! t 1' 1' c) o o o @ -I -I (» n 7 1 T l, 1' 1' l, 1' c) c) (o 1' l, l, 1' 1' l, 1' t l, l, l, n 1' l, 1' t o c) o§ l, ll 1l l, l, l, T l, 1' T ! 1' n ! l, 1' l, o o À x v 7 n a n a a u n v 1' T T 1' fr 1' 1' À u a D o o N l, 1' 1' v n 7 n 7 æ 1' 1' l, C) c) À v v 7 o @ 7 v a a a a 7 a n a 1l 1' ô ô c) À5 x -{ a a v v 1' o o o o c) o oÀ x x -{ x x x C, C, o (nÀ x -{ x x x x o o o {§ x x x x x x x x § @ -.1 { -{ -{ x x x x x x x x x (oÀ -J i -t --t { -{ x x x (,r x x x o x x x x (, 6 l§ x x o m o) { @ (o o @ o x x x x N o -{ N v m N N + x ]§ o =m -{ -{ N z à -{ N x x x G o N z x x x x x x o -l x N I x x x x x x x -.1 m x x x x x x x o o oN x x x x ! c) o ô o N C @ 7 -i i o o o c) m -{ -{ -{ x x x o o c, o » v ô) v c) C) N (o (r) o x x x ! x x x x o c) o { x x x x x x o c) o N À ôo x x x x x x o o ! ! o 1' ! 1' ! x x 1' ! -o ô@ T 1' t ! ! 't ! {o ! ! ! o T 1' ! ! @ .E o ! t @ l, x x 1' o§ x x x t À x x x c, C) x x x x x x x x x x ৠi x x x x x x x x x oÀ -{ -{ 5 -| x x x x x x x x o c, c) \là à @ I @ o o m N o I (r @ { @ @ No N N x }§ N x o, -{ N I mv x 1§q -{ N Ot lft }o z -{ { À) o @ z l§ x 6 o x o C o + x o o o, l§ E o \l -l x x o) o N x x x 5 g x x x aj o { x x 6 {o 6o .oo x x o) x x â t x x N -{ { x x x x o§ x Àà x x x oà x oà {à è @ à 1O o (n q o m<:rTc)x loIt (D o ooooooooooooooo lÈt l^ o lrlo o ooooooooooooooo lo p.3 tol^ 6 oâ ê ooooooooooooooo lôl3 :, o. q l'. s æ O\ æ { æ t, l, Ur qrt § tJ (JJ a i.) { tJ O\ t\) tJ O\ \O-l O (rr O\ O tJ (.,t o, bJ ur (, O\ { { \O t\) l.J O\ { æ u --I æ (,r I 3 Ë ? No o o o o O o O o o tr C C c C C C c C C ET m m m m rn m m m m .D H g) =aÀ m m m m =m m m m m ! o.{j\<' or P cL !r o oo o=. o\ â(D=ÉL 39=â 6'P.= -o oà P N) H nE, o @ (o ro (o (o (O (o (o J= oÊ a o (o (o ro (o (o (o (o (o (D. Or o to @ { Ot (, § (I, N) o * o =.D o E o q, oT a b (, N § q, or à 3 9^-r (n È (o (o ,§ (, (, o û) b É o D=3 CL -(r., H --l o H t E t= a o ô o= 3 0=z o !à o ÈN r !o 3 t (, o È o -{ o bl§ § (, N N N o o o Ol H (,l ï o 7 o I o În § ü) l\) § (, or È 3 ô GI a) { 6 ô (d CJ (d 6= o !8!9 =c, I =ô=ô CL= (r) o B3 P o Ol o (, N O) co -{ t ït !, o (,I o or (o û){ (, û, oOr § .o o o oT H 3 t = Ol \l @ (o à alr (, (ô N! tr, o z (,- I ?= (, H 1\) ,§ H { @aù ! o r.o à û) o (,I m 5 ôo o 0 a 3 o e. 3 o o (,l e. N N) 6 o o o o g ô r qc D ô (, ur N) -{ ! e (, (h nô N) U § ô ô { ! E É oT q, P I§ N È N 3 9. E g, @ ur Cr, Ol (rr Or o =! E GIo E -(D o P H l- I o ut @ Or o ôol 6 È, '8, or Èr G 3 o o o o o o o o I é o\ -(, F b --l ô c) ô C) CJ a) ô a) o hJ o oT o I N H N ts (., ts ts f o o\ Ol to (^, cl ur ul à o I o à UI D h.) F (D- g æ N ur q, 1§ Or (^, (Jl a,l ê 6r P E ùg oï F GI ts ts f o ro l§ (., t0 F F ts o 3 o! É (!r 1 N (r, ts lJ ,§ È UT I b N N 6r c' § F4 C L I5(mg/l ) æ ...\ Fl oo N sÀ) È. o (, (, (Ft (Jl (,l o -L Ln 1§ (, À \o (O o@ N o (o @ a rO- N tr , o o §, U) f, o (O ,, o o @ l o- 9,. N) U,. o I g v J (o o. o @ ï o.= a (.) N a f I oa o J (o I a @ 3 o § I o. I e ]TI (». (o I a (,@ ? o o rf I oo\ 7 (O o @. O @ o o o) il a C ; o ? o, É E o (o o\ u.^ t+, o @ E + ! Ot oo) o\l 1 F} o t ..1 A {+ (o @ I H o @ + o \J 'l N r§ Â, J o =r il + (D.@ x =(.o L Fd o oo(o E ïr à a\t tocL I (o (oO (o o r o â H æu, o o o\ t§ =ch. o o (o o J o (o g - o il -{ o. o 9. O) o (o f g o (o o N j \ F}-a 0) @. (o o (o o (/) r) F I - (O { (o t o § J- (o o (o x (Jl E' JI. (o o (O a- a ô, , , (o , (O{ o I , (.o (O -l @ ^. 15bis Table 7 ENTOMOLOGICAL RESULTS ON OUEME AND TRIBUTARIES 1976 -2001 ABR= Annual Biting Rate ATP= AnnualTransmission Potentials ATPBRT= Crude ATP ATP Con= ATP Conected BETEROU lOuenp) ATCHAKPA (Ouerne) M'BETEKOUKOU (Ouerp) DJABATA (Okoara) t rl *r: i', ' *trb: ffi rra.;+t ;:r'tisoti: ;**r \tt.'-d ;! I#Ë!* rdfr, i'Àtpbur: {976 117æ 211 1977 262æ 452 1g7C 25368 591 1380 0 26160 2112 1975 3Wà2 753 18717 2ü71 125653 21il r980 &12 ææ tm 24æ 86S99 6206 19tt 18338 82 152æ 116 46605 2820 t9t2 1tr68 Æ 9168 1Tt 63195 1644 19813 w7 43 Æ't6 182 43/,25 767 198,1 16301 21 327æ 1831 fru 2ffi 1985 26§ 32 33171 7æ sszil M ,988 1512. 108 æ981 2æ e4113 29/,2 1SC7 14666 162 90s0 257 53403 't011 1988 616 181 605 10 6016 508 1989 4729 220 12685 750 2co75 2536 1900 21ÿ. 82 3068 75 5812 )r2 1991 1æ4 158 37æ 392 1?i37 2035 1902 911 0 2491 24 1æ12 1500 1993 ÿ2s 6 21û 0 7386 855 25zJ 116 ,l904 ,1808 121 103 2125 259 259 11100 1106 1@ w 1g 14 1905 æ 112 56 871 I I 7W §7 u3 218zJ 1505 1435 l99t 33æ 2A 14 518 28 28 5495 525 476 w2 552 552 1997 ffi7 94 45 19'ts 88 88 7279 æ2 u3 113S! 605 5n ,90t 7576 77 14 't795 0 0 7859 509 245 1fr20 61 262 r909 6358 35 0 14æ 0 0 12ÿ(J 52. 298 11475 357 189 2000 16570 119 56 1615 72 47 11717 1113 10æ 't71æ 634 531 2@1 14552 119 21 7N 0 0 8531 399 294 13690 473 261 L6 Table 7a ENTOMOLOGICAL RESULTS ON OUEME AND TRIBUTARIES 1976 -2001 ABR= Annual Biting Rate ATP= Annual Transmission Potentials ATPBRT= Crude ATP ATP Corr ATP Conected Effif ffiË ffi ffiffifr H:iffi ffi ffiffi ffiilffi fffin Hffi $77 1978 117§ 37 §270 194. 9600 0 1g7g 154608 ,1919 131932 8108 422ÿ4 121 1080 7ffi7 17æ 94709 8095 75147 5049 t08t 2æ70 385 57835 1120 24110 n7 1gE2 7214 3/]95 19062 378 320æ 278 25635 221 198:t Æ263 2415 16527 0 30328 607 14652 223 1084 76976 3111 59771 û2 70737 951 51035 21 1985 66430 212 44C24 535 51345 186 17368 57 1986 35102 1147 26fft0 138 38514 846 46995 æ2 r987 41325 7n 56453 431 40050 197 37552 499 lsES 4062 55 6626 n 22050 w 420 0 1989 18283 't113 3137 74 13680 547 5185 38 {990 7133 m 654 30 7279 393 4309 156 1S91 æ17 801 10tr3 425 14094 't0îN 6390 150 1Sg2 627 w2 1055 60 7772 197 2123 43 r993 5982 160 w 0 8552 216 2352 6 ,994 8703 118 118 1151 215 198 16111 1323 1242 14132 290 2Æ 1995 5962 448 48 N2 93 u æu2 1 190 1118 5590 35 28 r096 M1 873 306 432 0 0 12991 361 270 6æ3 70 49 r997 5555 't33 62. 3205 324 298 1æ32 767 515 't0219 116 71 199E 2831 140 0 1950 35 35 16118 501 208 6557 65 42 1999 9366 524 166 1575 28 28 17410 356 'l49 6949 91 28 2000 12825 't37 119 1655 0 0 10459 331 296 7fio 63 28 2frO1 7275 49 49 970 18 18 12024 453 210 9897 108 56 16bis Table 7b ENTOMOLOGICAL RESULTS ON OUEME AND TRIBUTARIES 1976 - 2OO1 ABR= Annual Biting Rate ATP= Annual Transmission Potentials ATPBRT= Crude ATP ATP Con= ATP Correc{ed BAREROU {Yerou Maro) ATCHERIGBE {Zoul LANTA (Kouffo) KONFOKPA (Kouffo) ri'' ;:Â"r{mm ,tÉÂkù *#,r ',À*ffi": :rH( ,Àïr0tr .i',, 6661 i'.^iÉtir"; : .TEFT ",*ir,*rtr,l 'ffP,&#- 1076 1977 Il,I O so U 4AO^ AAA2l aa 11 198! 1757 _a 1a25 19E2 125D7 46 7974 s{tr) 43 0 1983 5715 318 5519 397 143 0 188'+ ô lD3 30 20627 793 5S6S 20s 1985 24554 148 41J63 937 10r 15 0 1966 tlôlc I/J 4ëOë 4 tJ 40e9 É1 aa Ân tarlÊ, ao '!989 8''30 55 10450 s88 1990 1471 0 512 38 1991 16334 91 4900 324 1992 zoé U 636 JJ 19S1 6eà 0 ÿ32 50 iS9,1 1297 U U 4/O tô lô 1895 {ôoa 1^1a c c aaÈa ôâ aaÈa lAe NE' 19_q7 800 5_',r 53 114a 49 49 1_',r_'r 0 o 1998 7115 116 2A 1575 37 4 518 91 14 1S99 385 U 0 2M5 I û 30 0 3244 2E 0 n 2000 ttt J 3951 100 181 5 U "0 2001 1875 14 0 5764 77 56 24 0 0 F- l o Y JO_y_<= PXÉ g)<>HË.' t++ o o o) O) @ o, t- o) (o o) ro o) b0 E s p o) .;o (f) o) IU (§ =]U c{ f o o) o cb0 É. .C o O) 'üc o o co o) co o) æ @ Ol @ @ f-- @ ,r (o @ to @ § Z @ (r) @ N 7 @ @ o r' @ o o o o o o o o o o o o o a) o o o o o o N o @ (o s N a) ! l USV co L- 'T] ABR (o C N.) C^) (, -{ (o o o o oÀ o oo) o o@ o o o-t o o o o o o o o o o _\ o o o o o o o o o o o I (o! o@ -Æ @ @ N @ G) §@ ) (,@ ,/ @ o) @ ! >E A (o æ @ @ @ TD I v @ @ o o (o 9. C f m E(o f. Zo f, m a (o { (o » o v IE 0, (o a C N -{ o. g 4 @ f m o) (o a §(o (o (,l (o o, (o \.1 (o @ (o (o o o +t+1 (»=oo)ur> csilrg (ô' q, J o (D @ r{ H' æ N ATP o oN) (rJo o§ (rlo oo) o--t o o o o o o o o { C» { @{ { (o -___ o@ - >{ @ J I -- @ N @ o) Ào ql@ @ o, @{ A m@ (o { o ! V@ @ U'@ >I I o (I, c @ o m o e. (o 5 =m J l f (o @=' N o (o d Crt e c, À«, 4 (o (o = Ol (o C" {(o (o @ (o o o +il I=ü >tæï4ri rcQâE ô C \o rrd P. ATP N P I N N (, o) à (rl o C'T o (,l o (rl o o o o o o o o o o { c» { @{ (o{ o@ @ J @ N @(» l (DÀ L-- @ (D @ o) {@ @ j { m @ (o ! v o ÎD o(o >I @ o I c TD m (o (D o 9. =m (o :, J =. (o:, (o ]§ o (o il (» ? Cl (o À d (o5' (o C'I (o o, (o{ (o @ (o (o o oJ +tt àPiN>> ;pÉ-ez o= \0 o d (â ts. æ H { o ! â N N) (, (, (,t o (tt o oÜr o o o o o o o o o@ @ J @ N) @ (r) E+i+i+IIIH;i;tji§ @§ @ (,l @ -' o) âs.L::i-illi: i;T.--r:a; '.- :'-î".-: *'l' @ { Eli+I [ -...;à -. ).*' ilt -- -,*i]:: @ @ ii+IÉ-". "--: (o@ {ro mo { F trE mm==tD(p mm{-{ ooxx xxCC CCoo Joo ta aÈr N ooNÜI f4 ts. æ -{ É ! n o I I N N) (r) G) (, O (, o (Jl o CN o O o o o o o § o o O o O o O o o@ @ J @ N) (,æ À@ @ (rl Éi æ O) ?,WW æ ! @ @ æ @ ffi mo { 7(O ! CNJ à7 (o o , N) . .,:. C (o ô G) o (o À =q (o (,l { (o O) (o ! (o @ (o (o o Jo NI CCoo oô oo ==oo I {È. tl N N(,|oo F{ 0q FI ! o I J J J N) N) À O) @ o N) À O) @ o O o o o O o O o o O o o o o O O o O O o o oæ @ J «tN @ N) n_=I ,tL @ ü) §E; À@ @ (Jl @ o, {æ @ @ @ (o mo arv(o (o N) (,(o (o À (o (rt (o O) (o ! (o @ (o (o o Jo EII oo-.{ -{ -- xx!T JÀoo oott N(,I N N |! 0a { n l, o I J N) N) (j) G) § § (Jl o (, o (,r o (Jl o (Jl o\ o o O o o o o o o o o@ @ J @ N) @ (r) §@ @ (,l @ O) {@ @ @ (o@ !-{ TD mo m V(o { @r vm (o o N) c (o o) §(o (o (rt (o o) (o \l (o @ (o (o o o J ooNI rà N oott N) (,l J F{ ts. 0q ATP \] o oN) o(^) o§ ocn oo) o o o o o o o { o) { {o (o o@ ) @ - @ N (o@ @À @ (rl { @ ! O) o @ C m J «) @ =m @ eË(o I { o (D 2, (o o ID e.) c (o f. { !§ (of (o o v o) m (o il @ § 3. (o o. (rl q (o (of O) (o (o @ (o (o o o +il >z<â2rt v N o 5 rÉ æ ATP 0) rN(r)À(,lo){@(o ooooooooo )o oooooooooo )d eo -a 1. I ee eÿ dd -o{ o ee C (o m m @ @ =m n 0o ) I u, { @ o e. n )f TD 5' c s (ct { o æ, 9ÿ, d m I 3. @ qo. .9d I (o:f '9d oo rDx>+il trrDo>>-.r morf,rcm q>n(-o §N TD d m (! rÉ ts. 0q { |1 ! o ts A J I æ N) À o) @ o N) § o o o o o o o o o@ @ I @ N) @ Cr) §@ (,læ ffi @ O) æ \l lfl:N..\,\^^/. I -r r: x-l æ æ rËsg ''* 1i:' t'' @ (o { ! mo tr)+{'}ô/-ÿ1 x E aaV(o o C (o N) N§ .:..,: (o G) tr'1,ïÏ (o À (,(o (o O) \t(o (o @ (o (o o Jo trE rÀ,OO tt N N(,roo E H' æ IJ n { o ! J \o rN)O)§ (Jl O)'-l@(OO o oooo o ooooo o@ @ A æ N) @ o) Àæ @ (Jl @ O) {@ @ o $EE:: æ { (o '{,wffi ! rno {o ar7(o vrn (o o N) TD *E m (o G) §(o (o (n (o O) (o ! iil (o @ (o (o o Io oo@l r r§. oott N l§ (,r o\ rn 0a n o N -{ o ! N G) § (,ro!@ o o o o o oooo o@ @ @ N @ (/) §@ @ (,l @ o) {@ @ @ l!i @ (o mo { n(o T AJ (o o N U, (o G) @ §(o (o (,l (o O) {(o (o @ (o (o o o EI Jà,oo oott N(,I N F{ H. 0q n {'o o N N N G) o) § § o o(,| o o(rl o (rlo o o(,l o o(,l o@ @ @ N (,@ §@ (rl@ @ C» {@ @ @ { (o@ 1' É mo n ArV(o (o N = (o 7 ü) o (o À (o (tt (o C') {(o (o @ (o (o o o EI rà.oo oott N(,t N @ (olt c oT N) N) { ! (rto(,ro(,ro(,JJNN('O) o ooooooo @ N (,@ À@ #,w @ (,l @ o) {@ @ @ (o@ o(o { T' ffla TD n(o aN n (o m (r) v (o o è C (,(o (o o) {(o (o @ (o (.o o o EI J+roo tt N(,roo (oN) STUDIES ON THE OUEME RIVER 1991 -1992 Figure 23 SPECIAL 30 SEASONAL VARIATION OF S.soubrense Beffa from ( ( I \tit U ( ) 1 fl' -\'"- \ l*- \^/-J'-./\ NIGER L { V 1 I J, BURKI NA FASo ( ( \ ( \ ) \ x \ À V (-i \ l I ..? I \ { (_ \l Y -v () -\ ( L .*.x \ tt f \1 ) .l/ "{ \ ( \- }I' \ !À t \ 't.V 1 { ) t) / ( .U t ,lI \_, \/- \§< -§\V \ÿ^_k ç J \"{ \\L §. .-^\-rr4, >§ rJ U ( \- -J \r +< I _) Vt { Ç-^..- ô fr- \--{, f .--s t{.* ,,\_ I \_-J kt r« I t+..\ I I \, v^ Y ) I ! L c"/ ÿ i Æ .AI r h /\) f-\,4.\ \ } {^ u /, t) {_( .*.\ atr Y \ j f f \ { NIGERIA ?- \ F t -? , 77 k t I I L ,) v Jr((r af; tl t) 1t. *=t \1 {,/ it ,(- (À /< i. \ \ V I 1( \ .À- .T ( I _E=_ J+ -\ t 3 I )\ LEGENDE \ +' No contarnination I \i I Less contanindion hportant contünination u ){ 77-- \ l\ ) \) ffi Veryhighcontanindior )'\r !t Zomlrdl2 (1 8s trtro(D-C) (I' t{) -o o o ct) N L ro I o- I o o @ L C» (§ o .9 - o E o o t- .ct (U +, = (E _o t- z o o) f LL - o .Y o .Y +,o Io C =!È, o G' - t-E la-o GI ta- oo o o o o) oo f Lo .ct o= o. U) o- o o o z (t) o oo (§ G, ït o o oc, (r, .s N c) tr à0 'ri h F4 H. æ f.t o N o o @ o z o o q,o E a o 9r o) o (oc o =.§, !1 o o l o la Io L C o) lc c f l-Iu l(D l= la lo oTD q, L -1l c o o J - 3 o) o o OJ q)x E E o z g tr 3 o oET §) o o-l 3 6'= o (o il æ (o oI Jo N § o C'T trtr EOo il8sî N Fd 0e N o\ V) o E F FÉ É È Ê z, â o L1J rd lr Fr lr oeoeê(DehJàg\æe[.J5 \c §\o \o æ N \o N) (, § tr \o FË r! UI E \o rn -l Ur (â \o zF] o\ o\ N (, È \o ê\ -E] a \o \ow N) \o \oæ § § oo o\ §id \a §,E N)@ z 8ur \o z -i § § \o \o lrl t0, EÜ Ur L'I § { A\OF] tnÈ æ ÈEl Éz \o { \o § § æ -t L! { \o -L o \â ô I \o ÈÉ n (, F \o C F O Lfi \o È bJ rn E ê U) ô NJ (,r (Jt o\ \o É ô b.) tr, t\) E a t\) N) \o lr z Fd a ô 0e F F N z F -l rn o [1t N) t\) t\) \o § \o \o Fl N) o\ § u, bJ§J(, UI (,I ê(Àe F \o \o N) N) UJ \o ? 5\o oo (/r (.rt N tsü \ê I (,I -l rn \o F z § { \o I § \o o o\ hd È \o r< E o\ G(, ô \Oèr0 Eü §,- tt)= \o 'â) \â -l { ^) { oü o\ \) tr -t! Ilq ÊD, H EI \ê s3 a æ frd \o ?4 N) § Or \Ô >El oo t\) L,t æ z \â k l1l t! \o OLD ô o hJ F \o ô F t) t\) { \o c) oo 00 { \o (/)rrl hJ o t) t\) t\) o\ oo oo UJ t\) t\) L,I oo o\ oo (, § EË 0a N æ C') tt ô F F e -j Ez. B rÉ \.Ô êo o|o \Ô râÈ \Ô o\ -È, ? § o\ æ bJ t! ê 14 tïl i< I (JJ \o ll \Ô C \o è (/J§ { \ê 7< à ffi Ë.:tl.if t{:irittrïft tF.1::!*rrT.{ttf,it#. HI FU o \o È .§. \c) (,I tÎl §J -{ §J \c) i;:riïi z ôê o\ o\ ,uf È \o-HlrI \ê \o (â o\ .:ttü -§. UJ \o ar o\ \c) *I (4) §J { O\-r3E -\o =aÊ), z <ÈEl z *l tJ \ô tüt [.J \!f taJ ü1 oê -È. \c) cê Ia, 0 OE fn-Fl rri *ll oÈ7(2. I S= frJ \Ô AF N) tJ \Ô w \ê t.J{ oo t..J \c) F \ê i+}};.:{{{.:r-+1!:.tt}] oa ffitr eoo È i N bJ F E o t.J ffi r 1F. ô e rrj tJ \o (, o rr) F '^) b.) il E $.f.!il!Ï:ttti+hT: ô tJ H t.) (^) FI §J \o \o .È, \Ô tr o z l! ln T l§ \o v) ô E! F IY z xF H t)È tn trl ld § o\ æ o b.J \ \ol- \o È FÜ o .tl \o r \o \c) E (Jr 2 § F Fl i E] F E LlJ \0 (A- \ç) EI o\ \o \O Eü o ô \o td §H I È)' r-.1 ^r N)c/l \o l.(F o \o o \§ orn o\ tat z tD, hu E tita, EÉO a üE \ô frrn \o Frt Z { fr r-l z \o F' \t) I EF o \o L,r Lar \o o (rJ (J) qJ oo o bJ F F (D o rn N) N) \c) a oê oo o\ \o }J li §J t.) O O § o\ Èn 0e a C] W o oFt e F È rdrrl\)t\)(,J(, z, urcütcuteut t]] oeee(Deê LlJ \ \o \o .§ Fd o N \o \o È \o \o (À zrn o\ 00 Ur § I o È a '^J rn a \o C,)- \o E o\ 00 \o tr -l è U) (^ ô \OF \o§Ë -1 \o (A ^t ê), \o t.! \o z ts o\ L^,J z OH tr lra r_r FU (a ü\ox §), O æ t.) (/) \0 92 N \o t\) \o z o\ 00 EI (r) È § { \o rr \o il U) ô \o (,] UJ UJ \o o (^ (â (^ 00 b,J F o rn a I N N \o ù.) o 00 æ \o N) o t\) o 00 æ æ { rÉ H. T a o EÉ L., F F E- z C) FË LTJ rü '-lrn b.J b.J (,) (,t UT O(,re VUU tJ NJ \o \o (,t (rr \o \o§ #I.I--+{.ËFÉE+f t:+.r+JbÏ+Ët+ffi FSH \c) è È oÈ I \â rrj H \AJ Ur Èz \o F I |-{ \o X 1.1 \o \o (rt È rr[ \ê EI o\ \O-U) +r ô \o l! è71q o Ê0, NJ t.J \o F tJ N) \o F I 8ui oo oo o\ \§ - Lrl t! z §,J EI E >x ÈY \o- a üE H Lrl oo oo \o æ oo { ÿ= z \ê ^t=rJ!! Fq \c >i; \o ô \c) æ b.) F rn a \o bJ \o \o t.) § § { { \) tJ O t.J æ rE T N (, C) t! 'vI fr eF É æ, F, È rnz U) I bJ§O\* Ob,Jàlr Fi hd ecceooeôvvYvr-r!-rr-,- ld \o §J (j \o \o jtfr*+iÉ:Fj.lr:llllllll:iË;ifi .fi :III[.[ IiJIIiT#iT.!,: § b.J \.Ô E l'.) (/) aÈ' § HI§ oFl x I u, w ln t'^)- \o UI ;I-EIÈï.+Iï.I::ïI:E:I-+.?.EIF-1-T:.iUü z t1 È \o § tJ \o \o tn oô H r'i F td \0 a o\ ,^ô ffi m GE \J Ë r* N) (JJ \.o Eéts] \.1 o\ \o FI §)u \o O o\ tlN N)a li.l 1t!.!.!.!rra!at.i!.!, oOhi \^l tal D§ §l z FÜ TI, §)' E I -{ (t) üE XA { §o\ {€ o3hE !2 \o L^] \o FF §J € *;l U1 æ oê oo I o \J o F H+ {+t++1. F ffi; \o -È, \Ô T ô oê o\ \Ô \J 0rn c ffi lr t b-) È.J \o UJ \l{ o\ È.J èJ {F, \o (JJ \0 Fd 0q T' a ô Ed Ë F È a à F l.i rn rn eêcootJ§O\æC l- \0 \o Hffiffi: \Ô § T' N) N.J N) \o ffii æ oo oo § -l I E] EË: \o z ô UI -l :É t4^) \o E ln N) { oo \o F Ë r', æ { § (, ô EÉ I \o Ga rn o o\ \? ED ffiq §), - N)j \o F Lr) § \o \o F 8cÀ t\) o\ N) o\ â D§ §), ttl trl z tat EI I ÔY \o O t..) \o§ \o§ \o üE t..l rrl -J §t i:z z \o ÔH t! \c l Ei' Ë \o fn iA L,J \o § è t\) oo ô tJ F F \o \o rn o o \o \o b,J a lr t) { æ \o Oo ô t.) (, { o\ -J 5 rÉ 0c § a ô ED rtr F q 7, È z (rf rn EJ 19§o\æë§Ëâ oocooeoooooooooco \ l.r \o \o FU § o § \o Ë § \o § I E] EÉ \o z F UI - E1 § (Jt \o È r{= oo (JJ ô \o a UJ Lrr Lrr (â E \ê ô o\ \oGE r'i o §C '),t §,4 Llr Llr r, (,I \o fr N) { L'I \o lr 8El tJ N) o\ ô z HH tal Fü trlz Fe, tr Èll UQ (a (-|t o\ \o ü§ { N) o \o >rn w (, Lfr il >Èwz { z \o >F FJ \ê V) NJ è \o il (.r) o\ ô \o o oo o tJ oô l.) F F o o (J) \o (/)EJ (Jr æ L'I \o c}.) UJ \o { \o trJ L,I o\ N) r § u) (r) § § <> t.J N) § (/.) o\ { oê (J) § l! 0e o c) ET FU F F C F *j 'v2trl z EI l.rt.)(,5t,tO\-læ\O LIJ oooooeoooocooeeooo U ld FU \o ,:+:{.: : o §\o È \o El l..J \o r IT z oo æ À \ê EÉ È F UI ,Hfl{lslfl#.:.{.:Pdi:.B.lT tn ô i - ô Ë rr U) § À \o T \OH § § À \o BI \o \o !! N) oo æ ( ô o\ .À 'P o ffi §, t-r ,pF I tsû UJ æ \o Ë o\ { \o t.l::l 3r,r ô\ o\ UJ o\ tr .l Fl D§ J T! z ,l §)' Ial Eir Èt a t-..1 üE -J \o \< Il.l o\ UJ \o il xY. tJ UJ { z \ê FJ \o gF (r) \o § \o o oo ob.) o o j:l-l F F (à \o bJ o o\ N) \o rn o\ § \o ld V) N) w (, N) \o { N) § § § \o \o § N) Figure 36 43 AQUATTC MONTTORTNG STTES (AS OF 1994) STATTONS DE SURVETLLANCE AQUATIQUE (S|TUAT|ON EN 1994) , , I I .rL T l I t I \ ['"i. I ) I I ( ( I FA,sO I I I ,l 1 BENIN ( GHANA 11 I j I I COTONOU I 1.,1, LOME t o ABIDJAT.I assandra Fish monitoring sites * Staüons de surveillance de la taune ichtlologique Original Programme area o ln\ertebrates monitoring sites Aire iniüale du Programme Stations de surueillance de la faune in\ertébrée tâNiciding erûensions Zones d'extension des traitements larvicdes tr Sites no longer visited (Fish) W:72 Strtions qui ne sont plus üsitées (Faune ichtyologique) Area feated with iwrmectin alone Zones faitées à l'irermectine seul Sites no longer visited (ln\,ertebrate) I Stations qui ne sont plus üstées (Faune in\,ertébrée) Fig.37 44 EPI VILLAGES IN THE OUEME BASIN s QO, KU o o GARE o TOGO IGERIA A GOVI o o aTOSSO TOGO o o \ u- LEGEND O EPIüllage Table 8 45 DAtE:OB/07/99 SUMMARY OF EPIDEHIOLOGICAL OATA OMS / ONCHO (EPICRALl) PAYS : EENIN VisuaI Vr [ [age Survey Duration Pop. Pop. Prev. Acui ty Nunber Prev Number Vi [ [age Name Date ïype ControI Census Examin of mfs CHFL Examin Bt ird Bt ind 392 ABGAGOTJLE 7903 s À. t; 198 381 70.2 16-71 260 2 0.6 5025 AFtoNot I 8910 S 1 .81 176 110 34 .8 3.17 r 9110 H 3.83 160 125 23 .9 2.80 112 0 0.0 5026 AFFONOI I I 8910 s 1 .83 167 112 35 0 4.50 r 9',I 10 H l.8l 179 150 26 0 2.50 113 3 1.8 5116 NBORKO 9001 s 2.08 90 75 51.1 13.22 * 384 PENESSOULOU 7805 s -9.58 155 123 t 0-6 1.08 91 0 0.0 /.01 KOGBE IOHCN.JE 7901 D -8.67 16t, 152 60.1 13.97 124 2 1.3 8301 s - 1.67 111 118 81 .4 1?.O3 88 1 0.5 870? H - 0.83 165 111 67.7 27.39 132 2 0.9 û t *.t 9110 S 6.83 366 331 29.3 1.13 tt 9802 S 10.17 382 215 13.6 o.47 t 123 LANTA 7905 s 0.00 170 161 12-7 5 .00 115 1 1.1 9901 s 11.33 331 229 0.6 0.02 215 0 0.0 t ol roco 790t, s -8.67 319 303 6.7 0. 17 216 5 1 .7 5079 ZASSA-N'GBENOUOO 8912 s -9.00 331 231 11 .6 0.57 9802 s 10.17 316 130 0.8 0.03 t t tt COUNTRY : BENIN BASIN : KLU.J-AGBAL0,/ZCU rf 396 GOVr 7903 S 0. 00 292 261 57.7 11 -22 196 3 1.0 9212 S 6. 00 178 311 20.8 1 .14 7 0 0.0 951 1 s 7 .92 156 298 2.8 0.09 2 0 0.0 COI,JNTRY : BENIN lBAsIll : KcrrFFo'll r1 5217 BAGBORHOE 90'l 0 S -8.17 119 104 15.1 5 .55 * 911 0 S 6.83 79 51 33.2 2.39 * 9802 S 10. 17 86 60 16.0 0. 13 t EGEETAKOUKOE -9.00 5081 891 2 S 178 154 16.5 l, - 1.3 9410 S 6. 83 183 l4J 17 -5 0.77 * t 9802 S 10.17 205 lt2 7-7 0 .33 5O8O ESSEIIOUE 891 2 S -9.00 280 230 19.1 0 .91 9802 S 10. 17 3ll 178 3.6 0. 10 5OB5 GANHAYADJ I 891 2 S -9.00 288 215 21 -8 1.37 9802 s 10. 17 3r8 86 2.9 0. 13 Table 9 46 DAtE .aB/07 /99 SUMMARY OT EPIDEMIOLOGICAL DATA OMS / ONCIIC (EPICRALl) PAYS : BENIN VisuaI Vi t tage Survey Duration Pop. Pop. Prev. Acui ty Nurnber Prev Nr.rnber Vi[ [age Name Date Typ€ Control Census Examin of mfs cHtL Examin- 8t ird Bt ind 5027 UAR I -MARO 8910 s 1.Bl 1t? 296 60. /. 12 -19 5028 IJUUEERU 8910 s 1.83 Z0? 114 58.7 |t, .75 COUNTRY : BENIN BASIN : NANON/OKPARA t'[ 3-92 * *t 5032 BERADOUROU 8910 S 1-83 153 109 3t,.9 3t' 2'7O 5035 KOSSOU B91O S 1 .83 ??2 151 '2 t2.2 6-99 5033 OUROUBEROUNGA 8910 s 1.83 282 ?O2 i 11 0.72 t 5030 IJAR I 8909 S 1 .75 207 118 .9 COUNTRY : BENIN EASIN : OGOU/HONO r1 5O]7 OGOIJALA 8910 s 1.83 133 109 52.6 10-99 COUNÏRY : BENIN EASIN : OKPARA r{ 5016 AGBORO-KAMBON 8910 s 1.83 126 ?89 20.3 1.37 * ** 51,75 OJABATA 9411 s 6.92 308 250 3?.? 1.38 ** 990t, S 11.33 32t, 177 8.1 0.17 131 3 0.6 5081 GBERE 8911 s 1.92 113 1?6 20.5 0.99 ** KAEOUA 275 7805 D 0.00 212 155 69.6 17 -52 1?7 1 0.3 9802 s 10.17 21,1 115 15.7 0 .68 I t* 5011 KILIBO GARE 8910 s 1 .81 503 373 37.7 5.81 9111 H 3.92 383 222 37.1 5-65 2t2 1 0.3 391 HOKA 7903 s 0-00 196 189 53. 1 8.6t, I /.5 o-2 891 1 s - 9.08 16 111 36.0 5.32 19 0.3 9512 H 8-00 297 ?t,1 1.5 0.13 219 0.2 0KPA 5548 951 1 H 7.92 335 269 31.5 0.71 231 3 0.8 5072 OUOGHI 891 1 S -9.08 510 1?3 9.? 0.11 9802 s 10.17 6lra 298 0.5 0.00 SANDEOU 5073 8911 s -9.08 ?18 161 21 .5 1 .85 H cstz 8.00 96 83 9-9 0.34 80 1 0.6 lç8 uoR I A 790t, D -8.67 97 96 70.1 23.91 80 2 1.5 8304 s -4.67 71 50 63.2 31 .A7 12 0 0.0 1.1 COUNTRY : BENIN BASIN : NANOUUIH/IEROU 57 .6 8.01 5029 KIKA II 8910 S 1 .85 506 332 8. 85 0 0.0 9111 M 3.9? 384 ?01 51.3 186 COUNIRY : 8El{tN BASIN : I.IONONGO/CUEHE r1 ]13 SETEHS I 7706 s -10.50 351 302 55.1 11.52 ?15 2 0.5 lable 1O 47 oAIE:08/07 /99 SUMHARY OF EPIDEHIOLOGICAL OATA OMS / ONCHO (EPICRALl) PAYS : EENIN Visuat Vi t Ia9e Survey Duration pop. pop. Prev. Acui ty Nrmber Prev Nunber Vi t lage Name Date Type ControI Census Examin. of mfs CtIFL Examin Etind Btirrd 5159 AGONKOTJ 9410 s 6.83 296 270 6.9 0.16 t i ** 5078 AGONLIN-KPAHOU - 8912 s 9.00 138 106 72.2 13 -97 t t* 941 0 S 6 .83 136 102 60.9 1-90 t 381 ATCHAKPA 7805 s -9.58 531 119 æ.2 23.51 316 16 3.5 5880 ATCHAKPA(381 ) 9901 s 11.33 375 301 3.8 0.13 217 ',t 0.7 315 BANICRI 7706 s -10.50 297 220 69.3 21.80 161 1 0.3 t 09 EUE 7901 s 0.00 311 215 59.7 13.13 144 2 0.6 941 0 s 6 .85 527 382 20.6 1.11 27 1 0.1 107 H LAtt ' 7904 s 0. 00 276 260 67.9 11.17 186 3 0.9 9410 S 6.83 348 213 14.0 0.t7 73 I 0.2 390 IDADJO 7903 s 0.00 365 331 73.4 28.89 217 5 1.3 9802 s 10.17 131 ?76 17.7 0. 55 76 3 0.5 ?05 KOKO 7805 D 0 .00 115 76 &.1 36.79 67 4 2.3 9802 s 10.17 167 109 9.8 0.60 t * *t 106 LASSO- SAHORO 7901 s -8.67 ?39 210 0.0 0.00 135 0 0.0 5043 LEKPA 8910 s 1.83 774 151 20.1 0.86 t *t 55t l MADEIIGBE 951 1 H 7.92 540 175 13.8 0.60 1?0 5 0.9 399 MBETEKOT,,KOIJ 7901 D -8.67 295 229 78.O 19.59 ffi1 5 1.7 8304 s -1.67 281 134 80.7 10.21 95 2 0.6 8702 l'l -0.83 257 172 78.8 17.Tt 219 6 1.9 9112 s 7.00 301 229 18.1 0.41 * t *.* 5014 TANGUTEGA & ADJA 8910 s 1.83 212 126 51.4 8.32 t t ** 5039 TCHEDJANNAGNON 8910 s 1 .83 361 2U 37.0 3.31 t * *t 9110 n 3 .83 365 313 30.4 2.01 310 0 0.0 9802 s I0.17 364 66 4.7 0-29 * *t 5015 TOSSO 891 0 S 1 .83 300 191 57.3 8.35 r * *t 911 1 H 3.92 304 271 55.6 8.06 259 2 1.1 9901 S 11.33 132 ?51 5-1 0.18 r *t 316 UEUE 7706 s 0.00 203 195 61 .9 12.72 111 1 0.3 9904 S 11.33 295 151 0.7 0.06 67 0 0.0 Pigure 38 48 WHO/OCP/PET/BIS Onchoce rc ias is (' ontro I EPIDEMIOLOGICAI COMBINED DATA BY VILI,AGE VILLAGE : ZOUTO ( Code 400 I Nearest Catching Point ATCHERIGBE Health District DASSA-ZOUME Region ZOU Country BENIN Basin ZOU LARVICIDING mars 1989 TO décembre2002 IN POPUI-ATION IN COHORT IN SEMI-COHORT DArE lrYPr CENS EXA POS. PREV CMFL BLIN DATE EXA PREV CMFL lncid. DATE EXA PREV CMFL lncid. 1s7so4lD 279 2æ 164 æ,5 25,42 3,5 197X)4 8 100 54.23 197904 113 95,6 25,82 igæo4ls 242 166 1æ 80,8 49,68 3,85 198304 8 1m 90,69 198304 63 96,8 47,94 1g37t2M 255 166 116 70,8 31,74 6,69 't913702 q 100 73,31 10,8698 198702 54 94,4 38,95 10,8698 198911 S 244 128 83 7't,2 38,6 1 9891 1 I 100 1 19,08 21,üüA 19t)§)1 1 32 96,9 57,94 21.81818 1æ904 S 363 210 6 3,6 0,18 199904 8 12,5 o,17 0 199904 18 11.1 o,% 0 2fnl12M 322 m 4 'l,8 0,06 1,92 2fÆ112 8 0 0 0 2æ112 0 Epidémiological Trend 120 100 "-o,' 80 60 i 40 20 ô 0 1975 1980 1985 1990 1995 2000 2005 Year + PRB/ ---+*-- ClvfL - -cÈ - FFB/ Coh * ^, r- -- Clvfl- Coh - -x- - lNlC 02/1 r/2002 Figure 39 49 II/HO/OCP/PET/BIS Onchocelciasis Control EPIDEMIOLOGICAI COMBINED DATÀ BY VILI,AGE VILLAGE : WOKPA (Code 5038 ) Nearest Catching Point VOSSA HealthDistrict INDETERMINE Region INDETERMINE Country BENIN Basin OUEME LARVICIDING février 1988 TO décembre2002 IN POPUL,/ITION IN COHORT IN SEMI-COHORT DATE I Yrt CENS EXA POS. PREV CMFL BLIN DATE EXA PREV CMFL lncid. DATE EXA PREV CMFL lncid. 198910 S 243 18'l 9€ 54,8 7,89 1989'10 37 75,7 7,72 198910 85 72,9 7,æ 199'l I 1 M 193 185 93 56,8 7,U n 19911 I 37 81,1 4,52 1991 11 65 75,4 8,18 1 9951 I M 173 158 19 11,8 0,33 0 19§}511 37 10,8 0,08 0,89285 19951 1 6 17,4 0,18 0,æ285 2fo112 M 2AO æ 2 0,8 0,01 o 2fo112 37 2,7 0,03 0 200112 0 Epidémiological Trend 80 ,. -o 70 60 50 I 40 30 20 10 0 1988 1990 1992 1994 1996 1998 2000 2002 2004 Year +FREV Cil4FL - -o- - PFEV Coh CIVFL Coh - -x- - ltlC 02/l 1/2002 Figure 40 50 IVHO/OCP/PET/BIS Onchocerciasis Control EPIDEMIOLOGICAI COMBINED DÀTÀ BY VILI,AGE VILLAGE : KONKONDJI ( Code 395 ) Nearest Catching Point KONKONDJI Health District SAVALOU Region ZOU Country BENIN Basin ZOU LARVICIDING mars 1989 TO décembre2002 IN POPULATION IN COHORT IN SEMI-COHORT OATE fE CENS EXA POS. PREV CMFL BLIN DATE EXA PREV Ci,lFL lncid. DATE EXA PREV CMFL lncid. 197903 S 278 2æ 168 72,4 24,æ 197903 '15 1æ 24,27 197903 98 92,9 24,æ 199212 S 425 314 138 44,4 6,83 1,08 1æ212 15 53,3 3,95 1æ212 49 75,5 9,9s 19951 1 S 444 æ5 42 14 o,u o,44 19951'1 15 20 o,14 0 1 9951 1 44 25 0,31 2000æ S 5n 279 1,9 0,08 0,3 200003 15 U 0 o 200003 18 0 0 n Epidémiological Trend 100 90 80 -§ 70 60 I 50 I I 40 30 I o. 20 10 0 1975 1980 1985 1990 1995 2000 2005 Year -.-+ PFE/ -***§i** Cil/fl - -o. - FFEV Coh * -i.r.* - Cil/fl Coh - -x- - ll$ 02/I t/2002 Figure 41 51 IüHO/OCP/PET/BIS Onchocerciasis Control EPIDEMIOLOGICAL COMBINED DÀTÀ BY VILI.,AGE VILLAGE : MBETEKOUKOU ( Code 399 ) Nearest Catching Point M'BETEKOUKOU Health District DASSA-ZOUME Region ZOU Country BENIN Basin OUEME LARVICIDING février1988 TO décembre2002 IN POPALATION IN COHORT IN SEMI-COHORT DArE lrYPr CENS EXA POS. PREV CMFL BLIN DATE EXA PREV CMFL lncid. DATE EXA PREV CMFL lncid. rgzso4lo *5 m 167 78 19,59 1,69 1979(N 20 90 14,t2 197W4 1't4 92,1 12,æ t98304ls 281 1U G 80,7 Æ,24 0,65 198304 æ 95 41,42 198304 49 98 51,45 1ga7o21?'n 257 172 127 74,8 47,77 1,94 198702 n 95 38,01 6,52188 19,3702 54 98,1 51,95 6,52188 tsg4rzls 301 m 36 18,1 o,41 159412 n 30 0,46 n 1994'12 39 28,2 o,57 o Epidémiological Trend 120 100 o 80 60 ç--' 40 o 20 o 0 1975 1 980 1 985 1 990 1 995 2000 Year +PRH/ Cil/4FL - -o- -FFEVCoh CIvlFLCoh - -x- -h,lc 02/1 1/2002 Figure 42 5lbis WHO/OCP/PET/BIS Onchoce rc ias is C ontro I EPIDEMIOLOGICAI COMBINED DATA BY VILI,ÀGE VILLAGE : KOGBETOHOUE ( Code 401 ) Nearest Catching Point LANTA Health District KLOUEKANME Region MONO Country BENIN Basin KOUFFO LARVICIDING février 1988 TO décembre2O02 IN POPULATION IN COHORT IN SEMI-COHORT DArE lrYPr CENS EXA POS. PREV CMFL BLIN DATE EXA PREV CMFL lncid. DATE EXA PREV CMFL lncld. 1979041D 164 152 91 60,4 13,97 1,æ 1979)4 73 87 n,27 197904 7A u,3 13,97 1S3()4lS 144 118 92 81,4 42,O3 0,55 198304 Z3 100 42,42 '1983&r 44 1m 50,33 19{37t2M '165 141 93 67.7 27,39 0,91 19{37æ æ 91,3 26,93 13,04376 1%702 44 93,2 43,4 13,04376 rggnrols 366 331 78 æ,3 1,43 199410 z3 56,5 't,57 4,74æ3 199410 32 65,6 2,4 4,74æ,3 rggeozis æ2 245 28 13,6 o,47 199802 zi '13 0,31 0 19,9€c.2 % 19,2 0,51 0 Epidémiological Trend 120 100 o. 80 ç o 60 o- 40 I 20 x 0 1975 1980 1985 1990 1995 2000 Year +- PRH/ '--*e*- Clvfl - -o- - PFB/ Coh - --;- - C[/Fl- Coh - -x- - [S 02/t 1/2002 52 RECENTE EVALUATION OPHTALMOLOGIQUE DANS LE BASSIN DE L'OUEME (Bénin, Décembre 2001) Tableau 11 : Présentation des villages Taux de participation Village Bassin Recensés Présents Examinés Par rapport Par rapport aux recensés aux présents Wokpa Ouémé 280 230 164 58,57 yo 71,30 0 Moka Okpara 333 240 209 62,76 yo 87,10 0 Sandéou Okpara 84 49 42 50,00 yo 85,71o Madengbé Ouémé 551 340 274 49,73 yo 80,59 yo Okpa Okpara 414 277 228 55,10 Yo 82,3t Yo Zouto Zou 325 229 188 57,85 yo 82,10 Yo Total 1.987 1.36s 1.105 55,61" 80,95 o Tableau 12 : Résultats des évaluations parasitologique et ophtalmologique Taux de Prévalence Lésions Parasitisme Parasitisme Cécités en Cécité par onchocerquiennes cutané oculaire général onchocercose graves Village Wokpa 0,86 0,0 01,22 0,0 0,0 Moka 0,83 0,0 06,22 0,30 0,30 Sandéou 2,04 0,0 07,14 0,0 0,0 Madengbé 1,47 0,0 09,49 0,J3 0,54 Okpa 8,30 1,75 12,77 0,97 0,72 Zouto r,74 0,0 10,64 1,85 1,54 Total 2,72 0,36 08,42 0,75 0,60 Table 13 53 IVERMECTIN DISTRIBUTION IN OUEME BASIN ANID TRIBUTARIES Year Basin Mllages Gensus Treatêd Covêrage% 1989 BEFFA/OUEME 1 300 191 63,67o/o 1 989 KOUFFO 1 178 154 86,520/o 1 989 OKPARA 3 563 431 76,550/o 1989 OUEME 3 895 642 71,730/o 1 989 TEWE/OUEME 1 138 117 84,780/o 1990 KOUFFO 1 116 't02 87,93o/o 1990 OUEME 11 2976 1 820 61,16% 1 990 TEROU/OUEME 4 815 562 68,96% 1990 zou 24 3 187 2238 70,220/o 1 990 Zou (Zone 1\ 27 3716 2440 65,7 1990 ueme 11 2976 1820 61,2 1991 OUEME 35 7 649 4 830 63,150/o 1 991 zou 52 6 074 4 027 66,30% 1991 1 56 6993 4592 65,8 1 991 Oueme (23) 36 7790 4927 63,2 1992 ALIBORI/NIGER 4 1 292 816 63,16% 1992 zou 6 2 143 534 24.920/o 1992 1 116 32063 20378 63,6 1992 36 15235 12135 79,7 1992 Agbado/Moyen Zou (24 104 13043 8501 65,2 1992 Ht & Moyen Okpara (25 79 16498 10940 66,3 1993 OUEME 2 306 220 71,900/o 1 993 TEROU/OUEME 3 271 183 67,53Yo 1993 zou 3 1 001 442 44,16% 1993 415 1 30208 87650 67,3 1 993 Ouémé Zou 347 60692 44268 72,6',1 1993 Kouffo I 87 24400 15482 63,45 1 993 BasZou/Ouémé 151 32894 23682 71,9 1994 KOUFFO 3 627 157 25,04Yo 1994 OUEME 2 522 59 11,300/o 1 994 zou 4 1 247 290 23,260/0 1994 Z4 14 6557 4670 71,2 1 994 Bas-Ouéme/Bas Zou 157 39738 22545 56,7 1995 Bas-Ouéme/Bas Zou 154 39925 29704 74,39 1995 Zone3+Zone4 349 70379 53013 75,4 '1995 e 312 82478 58544 70,9 1996 305 75316 56009 74,36 1997 TEROU/OUEME 108 87 451 64 139 73,340/o 1 998 TEROU/OUEME 105 117 497 103 835 88,37% 1999 OKPARA 6 943 913 96,820/o 1 999 TEROU/OUEME 95 84 347 59 228 70,22% 2000 ADJIRO/OUEME 32 24 048 16 940 70,440/o 2000 ALIBORI/NIGER 206 145 850 110 953 76,O7Yo 2000 KOUFFO 135 139 432 105 154 75,420/o 2000 OKPARA 203 135 680 98 451 72,56% 2000 OUEME 382 300 417 236 040 78,570/o 2000 TEROU/OUEME 113 83 501 63 812 76,42% 2000 TEWE/OUEME 38 25 401 18 073 71,150/o 2000 ZOU 196 126 221 96775 76,670/o 2001 ADJIRO/OUEME 77 51 320 38776 75,56Yo 2001 ALIBORI/NIGER 100 78 384 67 504 86,120/o 2001 KOUFFO 191 123 654 103 392 83,610/o 2001 OKPARA 104 71 191 45 578 64,020/o 2001 OUEME 445 296 503 224 879 75,840/o 2001 TEROU/OUEME 168 130 458 96 567 74,02Yo 2001 ZOU 134 111 148 84 130 75,69% 54 Table 14 ABREVIATIONS Sigle Sigle Dénomination française Dénomination anglaise français anglais Acide désoxyribonucléïque ADN DNA Deoxyribonucleïc Acid Bureau Régional (de I'OMS) pour AFRO AFRO WHO Regional Offrce for Africa 1'Afi'ique Biostatistique et Biostatistic and Information System Unité de BIS d'Informatique Unit Banque mondiale BIRD IBRD V/orld Bank Comité des Agences partainantes CAP CSA Committee of Sponsoring Agencies Comité conjoint de Coordination CCC JCC Joint Coordinating Committee Comité consultatif d'Experts CCE EAC Expert Advisory Committee Comité conjoint du Programme CCP JPC Joint Programme Committee microfilarienne Charge CMFC CMFL Community microf,rlarial Load communautaire Organisation des Nations Unies pour FAO Food and Agricultural Organization I'Agriculture et I'Alimentation Diéthycarbamazine DEC DEC Diethycarbarnazine Unité d'Evaluation épidémiologique EPI EPI Epidemiolo gical Evaluation Unit Institut Pierre Richet IPR tropicale de Institut d'ophtalmologie IOTA I'Afrique Microfilaires par biopsie cutanée Mf/b Mf/s Microfilaria per skin snip Merck Sharp et Dohme MSD MSD Merck Sharp and Dohme Programme de Lutte contre Onchocerciasis Control Programme in OCP I'Onchocercose en Afrique de l'Ouest West Africa Organisation mondiale de la Santé OMS WHO World Health Organization Institut français de Recherche scientifique pour le développement ORSTOM en Coopération Potentiel annuel de Transmission PAT ATP Annual Transmission Potential Amplihcation génétique par la PCR Polymerase Chain Reaction polymérase Potentiel hebdomadaire de PHT WTP Weekly Transmission Potential Transmission Potentiel mensuel de Transmission PMT MTP Monthly Transmission Potential Programme des Nations Unies pour United Nations Development PNUD UNDP le Développement Programme Taux annuel de piqûres TAP ABR Annual Biting Rate Programme PNUD/Banque TINDP/World Bank/WHO special mondiale/OMS pour la Recherche et TDR TDR Programme for Research and Training la Formation concernant les Maladies in tropical Diseases tropicales Tatx mensuel de piqûres TMP MBR Monthly Biting Rate Agence des Etats Unis pour le United States Agency for international USAID Développement international Development Unité de Lutte antivectorielle VCU Vector Control Unit Unité de Planification, Evaluation et Planifi cation, Evaluation and Transfert PËT PET Transfert Unit