II WORLD HEALTH ORGANIZATION ORGANISATION MONDIALE DE LA SANTE ONCHOCERCIASIS CONTROL PROGRAMME IN WEST AFRICA PROGRAMME DE LUTTE CONTRE L'ONCHOCERCOSE EN AFRIQUE DE L'OUEST REPORT OF THE TWENTY-THIRD SESSION OF THE ECOLOGICAL GROUP Bobo-Dioulasso.06 - 08 March. 2002 TABLE OF CONTENTS Page SUMMARY OF RECOMMENDATIONS .....,,.......2 A. INTRODUCTION .........3 B. ADOPTTON OF THE AG8NDA........... ...........7 C. FOLLOW UP OF RECOMMENDATIONS OF THE 22ND SESSION OF THE ECOLOGTCAL GROUP ............ .......................8 D. VECTOR CONTROL UNrT ACTIVTTIES rN 2001......... ...................8 E. AQUATTC ENVIRONMENTAL MONITORTNG ACTIVITIES ......... ...............11 F. ECOLOGICAL MONITORING AS PART OF THE SOCIO-ECONOMIC DEVELOPMENT OF ONCHO-FREED ZONES..... ........1,7 G. ARRANGEMENTS FOR THE NEXT MEETING ..........17 H. READING OF MEETING REPORT FOR APPROVAL........ ........,.,17 I. CLOSUR.E OF THE SESSION ..... 18 ANNEX I : LIST OF PARTICIPANTS. ..................19 ANNEX 2 : LIST OF DOCUMENTS ......................21 ANNEX 3 : WORK PROGRAMME FOR 2002.......... ..............22 i j 2SUMMARY OF RECOMMENDATIONS Summary recommendations from the 23'd session of the Ecological Group were as presented below: Documentation and valorisation of OCP's output 1. The Ecological Group requested OCP to facilitate preparation and publication of the aquatic environmental monitoring outputs by members of the national hydrobiological teams (para l7). Utilization of national capacities developed by OCp 2. Existing expertise among national hydrobiological teams should be used in special intervention areas where larviciding and thus monitoring would be effected (para 58). for envi Leone 3. Status of previous vector control, environmental monitoring materials and human resources should be reviewed by member (s) of Ecological Group and OCP staff, to provide basis of future involvements (Para l4). A basic aspect of intended OCP database 4. OCP was requested to document GpS determined sites as a basic component of database (para 16). Aquatic monitorine activities for 2002 positions and coordinates of all study 5. Monitoring activities during 2002 should be on the same water courses and at the same frequencies as in 2001 (Para 58). Joint Hydrobiologists/Ecological Group meeting 7 . The joint meeting received summary reports and presentations related to issues listed below for discussions and comments. Issues related to OCP's ending from the Programme Director; ii) Summary simplified synthesis of trends of aquatic fauna 'reaction' to larviciding in representative rivers from hydrobiologists. iii) Special subjects from members of the Ecological Group, invited experts or other participants. a) General information on OCP and APOC 8. Providing general information on OCP and the African Programme for Onchocerciasis Control (APOC) the Director with reference to OCP again said the Programme and its activities would end in December 2002. Naturally therefore, almost all current pertinent information on OCP were related to the closure of the Programme and information of most concern, related to the following: Special intervention zones (Upper Oti, Pru, Tinkisso and Mafou basins): The Director said there has been intense discussions with the EAC on what was to take place in these areas after 2002. He reported that the EAC, as a result, had set up a working group which had met in Geneva in October 2001 to evaluate available literature and information on ivermectin distribution and vector control as basis for deciding what were the most appropriate actions to be taken in the areas. Eventually, the following had been recommended for the areas. In the Oti basin (in Togo and North-west of Benin): Vector control through aerial larviciding for five additional years together with ivermectin distribution up to 2012. The other areas: Ivermectin treatment only. In Sierra Leone: The EAC, based on all available data, recommended ivermectin distribution to control onchocerciasis when it became realistic to undertake the activity. However, the World Bank intends to support a vector control programme in Sierra Leone. The Bank is therefore sponsoring a mission to Sierra Leone in April 2002, to review conditions and initiate the writing of a project proposal which shall include othcr health issues. The Bank makes it clear however, that the considered control of onchocerciasis by vector control would not be approved without an environmental conservation component. Thus, the issue of impact assessment is to be discussed by the Ecological Group. On OCP data and publications: the Director indicated the following: - The OCP in collaboration with the Erasmus University in Rotterdam is planning to put all OCP data together as a database that would be available to all in the future. - OCP expccts action on the proposed preparation and publication of a synopsis of scientific results from environmental monitoring and related activities. 9. A. INTRODUCTION 1. The twenty-third session of the Ecological Group of the Onchocerciasis Control Programme (OCP) was held at Bobo-Dioulasso in Burkina Faso, during 6tn - 8th March, 2002. The session was preceeded by a Joint OCP Hydrobiologists-Ecological Group meeting. Both meetings were under the chairmanship of Professor V.H. Resh, Chair of the Ecological Group. Present at ttie session were four of the five-membered Ecological Group, the Director of the OCP, Dr Boakye A. Boatin, invited experts and the senior staff of the Vector Control Unit (VCU) of the OCp (see annex I for list of participants). Opening Session 2. The chairman, Prof. V.H. Resh initiated the opening of the 23'd session of the Ecological Group with a brief welcome statement to members of the Ecological Group, invited experts and other participants. As part of his opening remarks he requested his colleagues to comment on overview simplified synthesis of monitoring results, which he had earlier requested the hydrobiologists to concentrate on instead of the results of their activities during 2AOl, in their reports to the Group. He thanked the West African Health Organisation for making facilities available for the meetings and gave the floor to the Chief of VCU. 3. The Chief of VCU, Dr L. Yam6ogo, welcomed participants to the 23'd Ecological Group session, expressing his appreciation for the positive response to the meeting invitation from the Programme. He indicated that the )3d session was to Ue ttre last session of the Group. Therefore, the VCU's request for advise and recommendations from the Group for the future was urgent. Dr Yam6ogo then thanked the Ecological Group in advance for the anticipated output of the session and promised implementation of its recommendations. He then handed over to the Chair. 4. The Director of OCP, echoed the welcome of the Chief of VCU and the chairman of the Ecological Group to members of the Group and other participants at the meeting. He observed that although the meeting was officially the last for the Group, there seemed to be more work to be done. 5 . The Director said as OCP comes to an official end, it was possible to review past events and observe that the good things that happened to OCP included the situations that the hydrobiologists had always been nationals working in their countries and the Ecological Group had always Seen completely independent. The situation of the hydrobiologists, he explained, makes them available within the countries for possible follow-up activities of OCP while the independence of the Ecological Group allowed for expression of opinions other than those of OCp on results and impacts of the Programme's activities in the open scientific world. The Director wondered how the world would have viewed the Programmes results without the independence of the Ecological Group and their working with the hydrobiologists. 6. On the recognition of hydrobiologists by the Programme, the Director said that at the Joint Programnre Committee (JPC) meeting in Yaounde, Cameroon, in December 2000, the contribution of hydrobiologists to the Programme had been publicly recognised. Also, the Regional Director of wHo was prepared to provide a reference to any hydrobiologist when needed. 6supervisory team for larviciding and environmental monitoring is to be formed for Sierra Leone, locals (ie West Africans) who have been sufficiently involved in the 27 years of OCP's activities should be involved with a member or two of the current Ecological Group assisting in review of issues. 15. On the issue of preparing a synopsis of scientific results for publication, the Ecological Group regretted that, there was not enough time left for neither the Group nor OCP to contemplate preparation, let alone publication, of the original considered synopsis. However, it was eventually agreed that some scientific publications, worthy as heritage of the Programme would be made. The type (s) and strategy for preparation were to be further discussed immediately after the meeting. The Director then requested them also to consider the original proposed document to be donc within the next two-to-three years with reserved OCP support. 16. With reference to the intended OCP information database to be prepared by the OCP in collaboration with the Eramus University in Rotterdam, the Ecological Group requested the following to make the data usable: a) that it includes GPS determined locations and coordinates of all study sites and b) as much as possible include background and associated information to data sets. 17. In relation to the expectation of the Programme for joint publications from the hydrobiologists, members of the Ecological Group made their observation that, different monitoring teams often considered similar data from completely different perspectives. A situation which would be difficult to resolve without physically working together. It therefore called on OCP to assist in any appropriate way to resolve the situation. b) Landmarks of the Ecological Group with reference to the aquatic monitoring process 18. As indicated earlier in this report, the 23'd session of the Ecological Group was officially the last meeting of the Group, just as with the hydrobiologists. Having managed the environmentil conservation related issues of the OCP during the Programme's life time (28 years) it was considered that all stakeholders in OCP could learn from what the Group itself considered as landmarks of its environmental management. Thus the inclusion of the subject in the agenda for the last Hydrobiologists/Ecological Group meeting. 19. Briefly, issues and moments considered by the Ecological Group to have caused concern to them and stakeholders of OCP were as follows: Support of long-term usage of insecticide in rivers in spite of the "DDT syndrome" at the time. Thus formulation of initial environmental monitoring protocols and sampling strategies, which had to be rough, widely valid and effectively applicable by a range of personncl. Ten years use of one larvicide, temephos, with no detectable impact on the environment, which was the primary concern of the Ecological Group. However, resistance development in the target organism caused great concerns to the Group. Management of the resistance to larvicide leading to introduction of new larvicides(eventually 6) and their use by rotation: strategy resolved original problem and became recognised to have wider application. - The OCP wishes to publish by September 2002, a popular magazine, which might be titled'OCP book'. - An update of the '20 years of Onchocerciasis control' document, which shall review OCP work and activities from 1974 till2002 is intended to be done. 10. On equipment, the Director said: the intended Multidisease Centre to occupy the OCP premises in Ouagadougou would make use of majority of OCP equipment. The rest, just as vehicles, would be distributed to participating countries of the Programme to support oncho control residual activities. The OCP garage in Ouagadougou is hopefully to be taken over by United Nations' Agencies in Ouagadougou. 11. Finally on OCP, the Director informed the meeting that, as part of events leading to the closure of OCP, a ceremony was held in Washington in December 2001 to which the past Directors of the Programme and Mr. McNamara (President of the World Bank at the time the Programme was launched) were invited to be recognised. The next JPC meetingin2002 would be held in Ouagadougou to close OCP. To that meeting, the Director said, invitations would be extended to as many people as possible that have been closely and specially associated to the Programme. 12. On APOC, the Director indicated that the project document for Phase II of APOC operations had be accepted and approved by the Joint Action Forum (JAF). Thus APOC is to last till the year 2010, the last three years of which would be the "winding down" period. 13. Discussions following the Director's presentation were elaborate and intense, especially in relation to two issues. First was the implied involvement of the Ecological Group in the environmental conservation aspect of anticipated vector control activities in Sierra Leone. Second was the issue of preparation and publication of synopsis of scientific results of environmental monitoring and related activities. 14. Reference to Sierra Leone, the Ecological Group essentially reminded the Programme that the Group would not be in existance by the time of the Sierra Leone project activity. However, the Group summarised their previous involvements in ecological conservation in relation to vector control activities in Sierra Leone prior to socio-political destabilisation in the country, which brought vector control in that country to a stop. These included: i) A preliminary mission by OCP to identify fauna monitoring sites in 1989 and 1990. ii) Review of some of the sites by the Ecological Group in March 1991. iii) Support for identification and training of local personnel to undertake monitoring as a national team. iv) Reviewed five years monitoring results from five stations before cessation of activities in 1998. Therefore, the Group suggested that, rvhen a decision to resume vector control in Sierra Leone is taken, the old monitoring stations should be revisited to assess their state and potential use. Availability of the trained team should be ascertained. Finally, they also recommended that if a 7Support of the decision to undertake the'Leraba study' as a case study of a more holistic approach to assessing environmental impacts on aquatic environment: strategy and results widely approved with respect to original intention. Independent analysis of monitoring data to substantiate apparent "no long term impact" of larvicides on non-target fauna: Independent support of "internal" conclusions boosted image of OCP. Justification for appointment of a hydrobiologist within the Vector Control Unit of OCP; it improved coordination of national monitoring teams and their output. The Programme's financial crises starting in about 1987: managed mainly by reduction of sampling stations by selection of basin representative rivers. Introduction of habitat assessment at monitoring stations and photographic documentation of physical status of sites: Gave more credence to influence of wider environmental changes effect on non-target fauna compared to larviciding. Photographic recording of station could be reference material years after OCP in relation to future fauna state. - Emphasis put on status of sensitive taxa in study of recolonization of rivers by fauna after cessation of larviciding: reduced "background noise" in assessment of impact of larvicides on invertebrate non-target fauna. - Interaction with hydrobiologists: contributed to background information on monitoring results and development of national capacity in West African States. - Excellent relationship of Ecological Group with VCU of OCP: facilitated Group's output. However, regretted lack of similar support from some agencies associated with the Programme at large. c) Natural resources management (example of Waza-Lagone project) 20. As part of the Programme's support to capacity building of national hydrobiologists, Mr F. Kond6, a member of the Guinean national hydrobiological monitoring team, had been supported by the OCP for a training in environemental sciences. During this period, he analysed aspects of aquatic systems management of the Waza-Lagone Project in Cameroon. 21. Mr Kond6 reported that an aspect of his study included natural resources restoration, integration of interests of different stakeholders and assignment of responsibilities to the beneficiaries. of the resources. He suggested that the approach could be considered in the management of Oncho-freed areas. B. ADOPTION OF THE AGENDA 22. The agenda as presented in the table of contents was proposed by the chairman of the Ecological Group to participants and was adopted. C. FOLLOW UP OF RECOMMENDATIONS OF THE 22ND SESSION OF THE ECOLOGICAL GROUP 23. The Chief VCU reported that five out of six recommendations made by the Ecological Group during their 22"d session had been implemented. In support of impllmentation of a recommendation, the Chief of VCU presented samples of a published brochure entitled "Preserving the environment : a major OCP concern over the past twenty-five years" as recofirmended the previous year. Reference to the recommendation which was not fully implemented and relating to monitoring of land-use changes, a member of the Group reported having made contact with a group in Italy that could assist but required more specific information to make request to the group more definite. The required information was to be provided to him by appropriate members of the Ecological Group following the meeting. D. VECTOR CONTROL UNIT ACTIVITIES IN 2OO1 General overview of VCU activities 24. The Chief of VCU's overview of activities emphasised the impact of vector control on intemrption of transmission of onchocerciasis in the Programme area. He indicated that: i) The original Programme area, colonised by savanna flies transmitting savanna type of the parasite, onchocerca volvulu.s, was characterised by hyper-endemic situations. In this area, vector control was started during 1,974 and ended from 1989 with no ivermectin administration. Intemrption of transmission by only vector control is evidenced in the whole of the original Programme area by results of entomological surveillance and epidemiological evaluations. - For example, on the river Leraba which was even reinvaded up to 1978, entomological surveillance conducted four years after the cessation of larviciding confirmed intemrption of transmission even if the biting rate went back at its original levels. - Observations at other fly catching points in the original Programme area nine to ten years after larviciding has stopped are comparable to that of Leraba. ii) The extension zones had both savanna and forest flies transmitting savanna and forest strains of the parasite, had only some hyper-endemic areas and lower blindness rate. Vector control in the areas started in 1988 and ivermectin introduced as from 1989 in the total area. iii) Considering all Simulium damnosum species, only four catching points out of I07 regularly visited had Annual Transmission Potentials (ATP) of over 100 during 2001. - Two of the four points were accounted for by savanna flies. iv) The good entomological results have been confirmed by epidemiological surveillance. - Epidemiological surveillance undertaken two and ten years after larviciding was stopped at various points indicated that transmission had definitely been intemrpted. The situation suggests that vector control alone might have eliminated the parasite from the whole original Programme area. 9- This was in spite of transmission intemrption proving difficult at a few of the foci involved, such as at the northern tributaries of the Oti river in Togo. v) In conclusion, available data indicate that in West Africa, where simulium damnosum s./. is a very efficient and highly migratory vector, onchocerciasis transmission control had been effectively achieved by l4 years of vector control alone. Onchocerciasis is no longer of public health importance in the Programme area. vi) Where vector control and ivermectin administration had been effected simultaneously, as in the extension areas, intemrption of onchocerciasis transmission and infectivity rates of the flies both reduced earlier compared to the situation in the original Programme area. 25. To maintain the transmission intemrption gained as new settlements develop in the Programme area, while the OCP comes to an end, it had been the objective of VCU to develop national capacities for effective surveillance to detect any recrudescence of transmission. To achieve the objective: i) National entomologists continue to be trained since 1998, to employ a low-cost surveillance approach using a pool screening method which could be used as an early alarm tool. ii) Training manuals are being finalised for the countries. iii) National entomologists are being involved in day-to-day operations of the VCU. iv) The Unit was facilitating collaborative working of national entomologists and coordinators. v) Efforts were being made to integrate all the above into national health systems of the countries involved. Aerial Operations and Larviciding a) Aerial operations 26. During 2001 the vector control unit had five helicopters at its disposal. Major activities of the aerial operations' section aimed at enhanced entomological results, better management of insecticide stocks and effective larviciding involvements. As a result of these activities combined with iyermectin treatments, entomological and epidemiological results obtained, made it possible to suspend aerial larviciding in seven river basins at the end of 2001. [t was therefore possible by then to make use of only three helicopters in 2002. 27. Overall hydrological observations made during 2001 indicated that the dry season of the year was longer compared to those of 1999 and 2000. Thus significant deficits in discharge were recorded in majority of rivers, especially in the eastern zone of the Programme. 28. During 2001, use of biological insecticide (8.t. H-14) increased to 75% of all seven products used. Carbosulfan stock was exhausted during the year. Therefore, only six larvicides would be used during 2002. b) Larviciding in the Eastern Zone 29. Intensification of larviciding which started in the basins of Kara, Keran and M6, in 1997 continued during 2001. Thus in 2001, river distance treated (about 2650 km) was about 47o/olonger compared to previous years. 30. Maximum treatment in the zone occurred during the 39th week (at the end of August) the minimum during the lTth week and suspension duringlhe l2th-l6th weeks (ie from beginning of March till end of April). 31. The general deficit in discharge reduced volume of larvicides used in the zone to about 50% of what was used in 2000. 32. The overall treatment strategy included rotation of larvicides used aimed at avoiding the development of resistance of target organisms to larvicides, and other recommendations of the Ecological Group. These were complimented with assessments of toxicity, susceptibility and efficacy ratios. 33. Entomological assessment at 51 regularly visited catching points showed that only two had Annual Transmission Potential (ATPs) above 100. These were at Djabata on the Okpara (ATP = 138) and on the Pru at Asubende (ATP: 140). 34. Fish kills were reported in the 43'd week on river Terou at Bief OU 5l I and in the 47th week on the Oueme at Bief OU 700 after phoxim treatments. Several factors could have attributed to the fish kills. However, with reference to larviciding, it was considered that a possible quick and drastic reduction in discharge between the discharge reading and treatment times could have been responsible. c) Larviciding in the Western zone 35. Larviciding in the western zone covered nine basins and a total of 6988 km of river distance during 2001. 36. Maximum treatment period was in the 51h week and involved 3995 km (of river distance), the minimum was in the 36th week and involved 583 km of river distance while treatment was suspended during weeks 37-39. 37. Susceptibility assessment of target organism to larvicides had been a preoccupation of the zone's activities with special reference to the Sassandra, Sankarani, the Niandan and the Upper Niger basins, For example, there is intermediate susceptibility to pyraclofos in the Guinea and Mali basins. While on the Kaba and Milo basins, the problem of susceptibility has been with phoxim. However, on the Kolente and the Mongo, susceptibility of target organism to all OCP larvicides is good. 38. Entomological results obtained during the year were generally good. Among 56 regular capture points none had an ATP above 100. An extremely good situation were noted at Yalawa with zero ATP and Fifa with ATP of 71. uResearch activities in VCU Fly movements, identification of vector and parasites 39. The species of Sintuliaru essentially responsible for the transmission of onchocerciasis in savanna zones of the OCP areas is S. sirbanum.The species is known to be engaged in migratory movements from South-west to North-east of the Programme area during the wet period (June- August) and from North-east to South-west during the dry and harmattan period (November- March). A study was undertaken, aimed at gaining a better understanding of the movements, the genetic variability and vectorial capacity of populations involved in the seasonal movements. To achieve these objectives, samples of larvae and adults of S. sirbanum from different basins and zones of the Programme area were collected, and experimental transmission was conducted. Technics applied for identification of species and caracterisation of vector populations include morphology, cytotaxonomy, microsatellite markers study and DNA (heteroduplex-) analysis. It is anticipated that results of the current study would confirm S. sirbanun migration patterns between basins and zones of the Programme area. Also, the study would provide insight into the risk of transmission associated with the migrations based on vector-parasite compatibility. It was suggested that, the issue of vector-parasite compatibility should be considered in future planning of activities aimed at assessing recrudescence. E. AQUATICENVIRONMENTALMONITORINGACTIVITIES Introduction 40. Major activities of national teams monitoring river fauna and environments in relation to OCP's larvicidng in their countries were as follows during 2001: i) ii) Monitoring of non-target invertebrates where rivers continue to be treated. Assessment of recolonisation of rivers status where river treatments have been Evaluation of fauna habitat quality. and fish communities and their populations by invertebrate fauna and evaluation of fish ended. ii i)and Comprehensive reports on the above issues on seven representative rivers within the Programme area have been submitted. Thus, only essential briefs are provided here. 41. In addition and perhaps more importantly, summary overview of 'response' of fauna per parameter regularly monitored during the entire monitoring period have been provided - as conclusions on status of the environment. Fish monitoring 42. Fish teams monitored seven rivers in three countries in the Programme area (C6te d'Ivoire, Ghana and Guinea). At all stations, common characteristics of fish communities and populations regularly measured were: Continuous occurrence of fish species known at Catch Per Unit Effort (CPUE) of fishing, Species richness ofcatch, and Coefficient of condition of principal species per station. Cote d'Ivoire 43. Three rivers, Leraba, Como6 and White Bandama were monitored at Pont Frontidre, Gans6 and Niaka respectively. Treatments on all the rivers stopped a minimum of eight years ago. - Species occulrence: During 2001, numbers of fish species encountered at stations in C6te d'Ivoire were 38 on the Leraba,35 on the Como6 and37 on the White Bandama. The species per station had all been encountered previously, except for the occurrence of Citharinus eburneensis at Gans6 on the Como6 (during February and December 2001). Previously, C. eburneensls had been known in C6te d'Ivoire to occur at the lower reaches of rivers but not at mid-sections, such as at Gans6 or the upper reaches of rivers. - Species richness of catch : Species richness at all stations during 2001 was high as the trend has been during the past five years. For example, richness recorded at the stations in 2000 and considered high at the time, were 36, 34 and 32 at Leraba, Gans6 and Niaka respectively compared to the 38, 35 and37 at the respective stations during 2001. - CPUE : Total mean CPUEs recorded at the stations during 2001 indicated stability at Gans6 and Niaka and a fall at Pont Frontidre. However, recorded CPUE at Pont Frontidre during 2000 was higher compared to records of 1997 till 2000. - Coefficient of condition : Mean "condition" of principal species per station continued to be stable as previously observed. b) Ghana 44. Fish monitoring continued on one river, Pru, in Ghana during 2001. The river is under treatment since 1987. - Species occurrence : During 2001, 42 fish species, all previously known to occur at the Pru station, were encountered. Among the 42 species was Hippopotamyrus pictus, which had not been encountered during I 995-2000. - Species richness of catch : Forty-two species were recorded at Asubende in 2001 compared to 52 in 2000. However, the current year's record was higher compared to pre-treatment and other treatment years'. - CPUE : Total mean CPUE recorded on the Pru during 2001 was about half the value obtained in 2000. However, compared to records of 1997-1999,that of 2001 was higher. - Coefficient of condition : Mean condition factor of species monitored on the Pru continue to be stable. i) ii) iii) iv) a) l3 c) Guinea 45. Three rivers, Sankarani, Milo and Dion continued to be monitored in Guinea at Mandiana, Boussoul6 and Baramana respectively. All the rivers were under treatment during 2001. - Species occulrence : No new species was encountered at any of the three stations in Guinea during 2001 and no indication of disappearance of species was noted. - Species richness of catch : The trend of high species richness of catch since 1997 was maintained in 2001. - CPUE : Compared to recent years, increases in total mean CPUEs were recorded on the Milo and Dion during200l while a decrease was recorded on the Sankarani. Hydrological deficits were considered accountable for the reduced CPUE on the Sankarani. - Coefficient of condition : The factor continue to be stable for all species at all stations as before. Discussion 46. Among trends of characteristics of fish fauna in relation to larviciding presented, that of Catch Per Unit Effort (CPUE) of fishing was the issue of discussion by the Ecological Group. The major issue of discussion was wheiher other sources of data on fish catches which could not be attributed to larviciding may not be used to show that catch trends had generally been reducing in West Africa. Finally, it was agreed that only data obtained as part of the monitoring process and protocol should be the basis of interpreting other aspects. This was mainly because the monitoring objective was simply to detect impact of larviciding and no other factors. d) Summary overview of "response" offish fauna to larviciding over monitoring period 47. Considering results and observations made at all the stations during over 25 years of monitoring, consisting of: pre-treatment, early-treatment, total-treatment and post-treatment periods, the following conclusion could be made with reference to characteristics of fish fauna monitored. - Species occuffence: All species of fish which were encountered during pre-treatment and early treatment periods continued to occur during post-treatment periods at all stations. It can thus be concluded that no fish species disappeared during over 25 years of larviciding of rivers. - 'Condition' factor of fisli species: No change in mean condition of any of the principal species per station was recorded over the monitoring periods. Therefore larviciding did not directly or indirectly influence the 'well-bcing'of fishes which is indicated by the factor. - Catch Per Unit Effort (CPUE): Catch trends were not consistent. Majority of stations showed declining trends during various phases of larviciding. However, increasing trends are being recorded in some rivers still under treatment. Also, there have been trends of increasing CPUE, in terms of numbers, while CPUE in terms of weight, decrease, or at best fluctuate (e.g. on the Oti in Ghana and on the Dion in Guinea). Conclusion on CPUE characteristic was that; whatever was the impact of larviciding on the factor, there were other factors which influenced trends in CpUE more importantly. Factors considered include: Fishing pressure, use of destructive fishing practices and poison fishing, all of which have been on increase in West African countries. Then Hydrological changes (eg. West African draught of 1980 to abcut 1990) and drastic changes in land-use pattems within the aquatic environment, mostly in the negative direction in relation to the aquatic environment. The Group also discussed and agreed that the presentation of the simplified synthesis of overall 'response' of fauna to larviciding would be presented to the Expert Advisory Committee (EAC) of the OCP with a preamble that more sophisticated analyses had been applied to the data with the same conclusions. Entomological monitoring 48. The monitoring of the aquatic entomofauna during the 2001 sampling year concerned on the one hand the monitoring of the evolution of the non-target fauna of treated rivers and, on the other hand, the study of the recolonization of certain rivers by taxa following the cessation of the anti blackfly larviciding. For a better interpretation of the results, the assessment of the quality of the aquatic habitat initiated in 1998 continued in 2001 at all the stations sampled. a) Results of the monitoring of the aquatic entomofauna on treated rivers The rivers Pru at Asubendd and Oti at Sabari 49. Larviciding on the Pru at Asubend6 started in 1988 and continued up to 2001. Regular monitoring of this river began in 1980 wcll before the begimring of the larviciding operations. With respect to the presence / absence of the taxa known as sensitive, Neoperla sp and the oligoneuriidae have not been collected in the drift samples since 1997. 50. On the Oti at Sabari, aquatic monitoring started in 1976, one year before the beginning of larviciding in 1977. The cessation of the regular weekly treatments occurred in 1992 but since 1998, the main Oti river is subjected each year to a few cycles of temporary treatments for the consolidation of vector control results. The results recorded on this station from 1993 to 2001 show the absence of Neoperla sp. This absence would be due mainly to a deterioration of the quality of the aquatic habitat caused by increasing human activities. The rivers Milo at Boussould, Niandan at Sansambaya and Dion at Tdrd 51. At Boussoul6 on the Milo, larviciding continues since 1989. The annual average densities of the total saxicolous fauna from 1984 to 2001 show a downward trend. The most affected group is that of the Ephemeroptera. A reduction of the taxonomic richness in the night drift and on the rock slabs is also noted. The taxa most affected in this environment are: the Heptageniidae, Tricorythidae and Neoperla sp. Larviciding combined with the pollution from mining activities are regarded as being the main causes of the disturbance of the fauna on this station. At Sansambaya on the Niandan, larviciding also eontinues since 1989. Since the beginning of the aquatic monitoring programme in 1984 up to 2001, the annual average densities of the total saxicolous fauna have been relatively stahle. However, the densities of the Ephemeroptera group are falling. The comparison of the results rccorded during the last three years of larviciding (iqqq- 2001) with those of the pre-treatment period (1984-1986) shows a reduction of the taionomic richness on the Sansambaya station. This reduction concerns especially the Heptageniidae and Oligoneuriidae regardless of the sampling procedure used. t5 On the Dion at Tdrd, the absence of pre-treatment data does not facilitate the interpretation of the data of the monitoring undertaken only since 1990 whereas the heatments had begun since 1987. Nevertheless, the results of the annual densities of the total saxicolous fauna obtained for the period 1990 to 2001 show an overall uplvard trend. Among this fauna, the Ephemeroptera are particularly represented and within this taxonomic group, the Tricorythidae seem to be the most affected by the larviciding operations. Summary conclusion on observations on entomofauna at treated stations 52. Information on the status of entomofauna at treated stations showed a range of 'responses' to larviciding. The range included: reduction, stability, increasing frequency of occurrence of some taxa and improvement in taxonomic richness. At some stations, absence of some sensitive taxa has been recorded. A discussion of the range of responses concluded that while larviciding could impact on the fauna, part of the impact could be attributed to habitat degradation. b) Results of the recolonization study Marahoud 53. The Marahou6 river was treated from March 1979 to June 1997. A few years after the beginning of larviciding operations and monitoring of the non-target fauna at Danangoro and Entomokro, some taxa such as the Tricorythidae, Oligoneuriidae and Neoperla sp although present in the night drift, had brought attention by their more or less prolonged absence on the rock slabs. Even in the night drift, the occurrences of these same taxa had known a fall during the larviciding The samplings carried out from November 1997 to December 2001 in connection with the recolonization study made it possible to note not only the reappearance of the Tricorythidae, Oligoneuriidae and Neoperla sp on the rock slabs but also an increase in their occurrences in the night drift. The quality of the aquatic habitat at these two stations is on the whole favorable to the colonization by aquatic insects in spite of the establishment of a brewery plant not far from the Entomokro station. Red Yolta 54. The Red Volta was treated from 1976 to 1994 but monitoring of the aquatic entomofauna was carried out at the station of Nangodi only from 1983 to 1986. During this period, very few occurrences of Caridina sp and Neoperla sp were noted. After the cessation of larviciding, the sampling carried out from 1998 to 2001 showed a rise in the occurrences of Neoperla sp while Caridina sp, although sampled during the prospections, remained absent from the drift samples. In addition, the quality of the aquatic habitat on this station is poor for the aquatic entomofauna. Nazinon, Ldraba, white Bandama, Comoe 55. The recolonization studies carried out made it possible to note that these various rivers were able to reconstitute their fauna from various sources. Thus, at the Pont de P6, the highest occurrence of some taxa from 1991 to 2001 (the Leptophlebiidae rose from 9%o of occurrence during the treatment period to 70%o after the cessation of the treatments) is revealing of more favourable conditions for these organisms during the post-treatment period. l6 At Pont Frontidre on the L6raba, the larviciding treatments did not induce any long-term disappearance of any taxa. However, after the cessatior, of tfr" treatments, a rise in the occurrences of most of the taxa compared to the treatment period was noted. At Niaka on the white Bandama, a recovery of the species Neoperla.qp in 1993, then ofCaridina sp in 2001 during the post-treatment period *u, noGd, a sign tf recoioni zation'by these organisms after a marqued absence since 1978. After the low densitiis of organisms noted on the rock slabs during the first l0 years of treatment, a relative increase in the de-nsity of the principal taxonomic groups, especially the non-target Diptera, Odonates and Coleoptera, was observed since the cessation of the sprayings in 1993. At Gans6 on the Como6, the post-treatment period seems to offer better conditions for theincrease of occurrences of some taxa. That of Neiperla sp rose from 10% during the treatmentperiod to 90o/o' and that of the Philopotamidae rose from 10% to 7O%o. On the rock Jabs, in spite of the end of larviciding, taxonomic diversity remained poor. Discussion and conclusions on the results of the recolonization study 56. Even if larviciding caused for certain organisms known as sensitive such as theTricorythidae, Heptageniidae, Oligoneuridae, Neopirla and Caridina sp either a temporary absence or a fall in their occulrence, the situation ii in the process of impiovement on all of the monitored stations. The Ecological Group is of the view that this level of impact of the antiblackfly larviciding on the non-target aquatic fauna was predictable and is within what it has always'regarded aI ecologically acceptable. It also notes and confirms the capacity of the tropical rivers studied to regenerate as long as the effects of the disturbances remain limited and therefore, their high resilience. Lastly, the Ecological Group marked its satisfaction with the results obtained by tf,e recolonization. Summary overview of responses of entomofauna to larviciding over the monitoring period 57 ' Conclusions from all invertebrates monitoring data, from pre-treatment through to post- treatment phases of larviciding, could be summarised as follows: at majority of stations, taxa numbers in surber and drift samples did not appreciably change during phases of larviciding. - taxa considered sensitive were present at post-treatment phase of larviciding at majority of monitored stations. 58. Based on discussion of all their available results till200l and the fact that y_ear of the Programme, the hydrobiologists made the following recommendations Group. 2002 was the last to the Ecological ' Monitoring and habitat assessments be continued till November 2002, with annual reports reaching OCP by the end of November. L7 o Additional qualitative sampling be done (eg with handnets) in relation to recolonisation studies at all stations to look for treatment affected invertebrate sensitive taxa. o Monitoring activities arrangements be established with appropriate national teams in the special intervention zones where larviciding will be continued. . Relevant updated databases be provided to national teams by ocp. o Workshop on data management be organisedin2O02 by OCP for hydrobiologists. their recommendations generally. They indicated that monitoring activities during 2002 should be on the same water courses and at the same frequencies (see anneie 3). F. ECOLOGICAL MONITORING AS PART OF THE SOCIO.ECONOMIC DEVELOPMENT OF ONCHO-FREED ZONES WAFEM Project The chairman announced that the Ecological Group and the Programme were still expecting news on the status of the WAFEM project. Study of impact of insecticide impregnated nets on non-target aquatic fauna 59. As a prospective study which would involve national hydrobiologists, the Chief of VCU introduced the above subject. He referred to a presentation relaied to the luUiect which was made to the joint Hydrobiologists/Ecological Group meeting in the previous y.ur. rL announced that theProgramme had been invited to present a proposal for the study, whictr his office had submitted. The proposal he said, had been accepted and materials for the .tuay nua started to arrive. He was therefore announcing the situation to the meeting. Discussion 60' In the discussion which followed the above, members of the Ecological Group provided more background information on the project involving the insecticide imprrtnated bed nets. TheGroup however indicated that it was not within their oilicial mandate to comrient on the study but supported it. G. ARRANGEMENTS FOR THE NEXT MEETING 6l' As the 23'd session was officially the last of the Ecological Group,s sessions, no arrangements were made for another meeting. H. READING OF MEBTING REPORT FOR APPROVAL 62' The main points of the Ecological Group meeting, as recorded during the meeting, werepresented for correction and approval. After some corrections and indications-from participants tolater fill-in on some sections, the presentation was approved. l8 I. CLOSURE OF THE SESSION 63' The 23'd and officially the last session of the Ecological Group was closed by the chairman on the 7th of March, 2002. As part of his closing remarks, the Chair thanked the Director of theProgramme, the Chief of VCU, his colleagu.r *d other participants for the active involvementduring the session. He also congratulated t is colleagues for guiding OCp to its end with the environment intact from any harmful effects of the activities of the pro[ramme. L9 ANNEX 1 LIST OF PARTICIPANTS Ecological Group Members Professor Davide Calamari, Environmental Research Group, Department of Structural and lulclio11l piology, University of Insubria, Via J.H. Dunant 3, 2t t0O Varese VA, ItalyTel: 00 39-0332-421546 - Fax: 00 39-0332-421554, E-Mail: davide.calamari@uninsu6ria.it Dr Christian L6v6que, Programme Environnement, Centre national de la Recherche scientifique, vie et Soci6tds, 1 Place Aristide Briand, 92195 Meudon cedex , France Tel. 0l 45 0l 5045 - Fax 0l 45 07 5124 - E-mail: Christian.Leveque@cnrs-bellevue.fr Prof. Anette Reenberg, Institute of Geography, University of Copenhagen, Oster Valgade 10, 1350 Copenhagen K, Denmark, Tel: +45 35 32 2562 - Fax: +45 35 32-2501- E-mail: ar@ieogr.ku.dk Professor Vincent H. R9sh, Department of Environmental Science, Policy and Management, University of Californ ia, 20 I wellman Hal l, B erkeley, californ ia 9 47 20, usA Tel. (510) 642-3327 - Fax (510) 642-7428 - E-mail: vresh@nature.berkeley.edu Invited Expert Dr Bernhard Statzner, qNRl Ecologie des Eaux douces et des grands Fleuves, Universit6 Lyon l, 69622 Villeurbanne Cedex, France - Fax: +33 472 43 ll 4l - Tel: +33 472 44 gO 34 E-mail: statzner@biomserv.univ-lyon I . fr Other participant Dr Souleymane Sanou, Coordonnateur national de la D6volution, Programme Oncho Direction de la M6decine Pr6ventive, B.p. 7013, ouagadougou, Burkina Faso OCP Secretariat !r B.A. Boatin, Directeur du Programme, 0l B.p. 549, ouagadougou 01, Burkina Faso E-mail: boatinb@oncho.oms.bf Dr L. Yam6ogo, vcU/ocP,0l B.P. 549 ouagadougou 01, Burkina Faso E-mail: yameoeol@oncho.oms.bf Dr L.K.B. Akpoboua, VCU/OCP, B.p. 36 Kara, Togo E-mail: catzonest@hotmail.com M. A. Ak6, VCU/OCP, B.P. 504 Odienn6, Cdte d,Ivoire E-mail: ocp.zo@aviso.ci M. M. Sarr, VCU/OCP, B.P. 504 Odienn6, C6te d'Ivoire E-mail : ocp.zo@aviso.ci ; cat_ocp_zo@.yahoo.fr M. J.M. Tapsoba, VCU/OCP, 0l B.P. 549 Ouagadougou 01, Burkina Faso M. L. Bakon6, VCU/OCP,0l B.P. 549 Ouagadougou 01, Burkina Faso 20 Dr E. K. Abban, council for Scientific and Industrial Research, water(CSIR/WRI), P.O.Box AH.38, Achimota, Ghana - Fax: (233) 21 77 7l 70 - Tel.: (233) 21 76 83 l0 - E-mail: wri@ghana.com Research Institute OCPA/CU/HYBIO/O2.O I OCPNCUIHYBIOIOZ.Oz OCP/VCUA{YBIO/02.03 - OCPA/CU/HYBIOIO2.O4 - 2l ANNEX 2 LIST OF DOCUMENTS Progress report on aquatic monitoring by OCP team - 2001 L. Robert Bakon6 & Joseph-Marie Tapsoba Annual report of C6te d'Ivoire - Entomology - 2001 Bihoum Moussa, Ayekoue Patrice & Kouassi N'Gouan Cyrille Invertebrate monitoring report of Ghana - 2001 J. Samman & A. Ampofo-Yeboah Monitoring of the entomofauna in Guinea K6l6tigui Nab6 - 2001 OCPA/CU/HYBIO/02.05 - Annual report of C6te d'Ivoire - Ichtyofauna - 2001 Kouassi N'Gouan Cyrille OCPA/CU/HYBIO/02.06 - Fish monitoring in relation to OCP larviciding in Ghana - 2001 E.K. Abban & K. Kwarfo-Apegyah OCPA/CU/HYBIO102.07 - Ichtyological report in Guinea -ZOOI Moussa Elimane Diop 22 ANNEX 3 WORK PROGRAMME FOR 2OO2 COUNTRY/RIVER/SITE PEzuOD OF SAMPLING /FREQUENCY TNVERTEBRATE January to April, and November COTE DIIVOIRE Marahou6/Danangoro Marahou6lEntomokro L6raba/Pont Frontidre BandamaAliaka Como6/Gans6 GHANA Oti/Sabari Pru/Asubende Red Volta/Nangodi BURKINA FASO Nanzinon/Pont Po GUINEE Niandan/Sassambaya Dion/Baranama Dion/T6r6 Milo/Boussoul6 Sankarani/N[andiana Once a month (1 day) Once a month (1 day) Jan., Feb.& Nov. (recolonisation) Jan., Feb., Oct. and Nov. (recolonisation) Sept. to Nov, (recolonisation) Jan., Feb. and Nov. Once a month (1 day) Aug. to Oct. (recolonisation) July to Nov. (recolonisation) Once a month (l day) Once a month (l day) Once a month (l day) Once every 2 months (2 nights) Once every 2 months (2 nights) Once every 2 months (2 nights) Once every 2 months (2 nights) Once every 2 months (2 nights) Once every 2 months (2 nights) Once every 2 months (2 nights) NB: The drift samples are taken only tofollow taxonomic richness of rivers
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