Onchocerciasis Control Programme in West Africa I Programme de Lutte contre I'Onchocercose en Afrique de I'Ouest JOINT PROGRAMME COMMITTEE JPC . CCP COMITE CONJOINT DU PROGRAMME Office of the Chairman Bureau du Pr6sident
JOINT PROGRAMME COMMITTEE JPC15.2 Fifteenth session ORIGINAL: FRENCH Yamoussoukro. 29 November - I December 1994 September 1994
Provisional aeenda item 5
PROGRESS REPORT OF THE WORLD HEALTH ORGANIZATION FOR 1994 (1 September 1993 - 3l August 1994)
Table of contents Page
SUMMARY 4
VECTOR CONTROL 6 Climatic conditions 6 Aircraft fleet and aerial operations 7 Treated areas 9 Insecticides and control strategy 9 Hydrology and teletransmission 10 Surveillance and entomological evaluation network 11 Entomological activities of national teams in the south-western extension area 1l Results obtained L2 Transmission t2 Post-control entomological studies t2 Monitoring of the aquatic environment ...... 13
MRMECTIN (MECTIZANR) DISTRIBUTION AND EPIDEMIOLOGICAL ACTTVITIES l3 lvermectin treatment 13 Epidemiological evaluation . . 15 Evaluation in areas where only larviciding is undertaken 15 Evaluation in the areas of both laniciding and ivermectin distribution 16 Migration studies t7 Ophthalmological evaluations 17
BIOSTATISTTCS AND TNFORMATION SYSTEMS . t7
INTERDISCPLTNARY RESEARCH 18 lnsecticides 18 Vector and parasite identification 20 ldentification of vectors 20 Identification of parasites by the DNA-probe technique . . 20 Epidemiological modelling 2l Immunodiagnosis 22 JPC15.2 Page 2
Macrofil Chemotherapy Project 23 Potential macrofi laricidal compounds 23
Potential resistance to ivermectin . . . 23
DEVOLUTION 23 Institutional framework for devolution and the roles of the main actors 24 Training . 24 Public awareness and population mobilization effort by OCP 27 Meeting on evaluation and programming of devolution activities in the countries 27 Meeting on the strengthening of epidemiological surveillance for integrated endemic disease control in West Africa building on the OCP experience . . . . . 28 Criteria for the assessment of the capability of the Participating Countries to carry out the detection and control of recrudescence effectively . 29
ADMINISTRATION AND SUPPORT SERVICES 3l Objectives, organization and functioning of services 31 Administrative costs 32
Budget and Finance . 32 Personnel 32 Supply and services 33 Transport and communications 34
PUBLIC RELATIONS, INFORMATION AND DOCUMENTATION ACTTVITIES 34 With the World Health Organization 34 With the Participating Countries 35 With the statutory bodies 35 With the Donors 36 With the aerial spraying contractor 36 With the scientific community 36 With the general public 37 Public relations and documentation 38 lnternal meetings 39 Collaboration with non-goverrlmental organizations (NGOs) 39 Jrc15.2 Page 3
FIGI.JRES IN ANNEX Page
Fig.l VCU plan of operations for 1994 N Fig.Z Annual transmission potentials (June 1993-May 1994) - all species infected by Onchocerca s.p. . . 4t Fig.3 Annual transmission potentials (June 1993 - May 1994) - all species infected by Onchocerca volvulus 42 Fig.4 Annual transmission potentials (June 1993 - May 1994) - savanna species infected by Onchocerca volvulus 43 Fig.5 Location of post-control entomological study catching points - 1990-1994 4 Fig.6 Zones of large-scale ivermectin treatment in 1993-1994 . . . 45 Fig.7 Ivermectin treatment coverage based on the OCP mode of distribution 6 Fig.8 Pre-control prevalence of skin microfilariae in villages from the original OCP area 47 Fig.9 Prevalence of skin microfilariae in villages from the original OCP area - 1993-1994 48 Fig.10a, Fig. tOb and Fig.10c Changes in the prevalence of mf and CMFL at Galamankourou (Mali), Gbeniki and Lougou (Benin) 49 Fig.11 Computerized mapping - projection of catching points in the OCP area 50 Fig.L2 Results of simulations of combined larviciding and ivermectin 51 Fig.13 Total OCP staff 52 JPC15.2 Page 4
SI.]MMARY
(a) In the eastern Programme area, the 1993 rainy season started quite late. However, the situation returned to normal after the heavy rains in July and August. In the western atea, the hydrological regime of the 1993 rainy season was more or less the same as in 1992. [n the two arqu, the 1994 dry season was severe. The rains started in May in the southern areas and in June in the northern part of the Programme area.
(b) The number of larviciding helicopters ranged between eleven in the 1993 rainy season and five in the 1994 dry season. During the 1994 rainy season, nine helicopters were expected to be used because of a better distribution of the guaranteed flight hours and supplementary flight hours.
(c) The more and more precise nranagement of aerial operations, the cessation of the sprayings in some areas and the decrease in the larvicide coverage in the areas under ivermectin treatment made it possible to save 1244 flight hours, i.e., about US$ 886,000 and 1 17 ,825 litres of insecticides, i.e. some US$ 1,100,000, during the period of May 1993 to April 1994, compared to the Period of May 1992 to April 1993.
(d) The insecticide rotation system has functioned perfectly. The acceptance by the Ecological Group at the beginning of 1994 of a seventh operational insecticide, etofenprox or Vectron, will make possi|le much more flexibility and efficiency in the larvicide spraying while controlling the appearance of a possible resistance.
(e) The entomological evaluation network has continued to be reduced in the original area as and *hen larviciding ceases. After the closure of three subsectors at the end of 1993, two new subsectors will be closed down at the end of 1994.
(0 The entomological results on the transmissionare quite satisfactory in the whole Programme area. Out of the 212 catching points monitored regularly, 92% have an Annual Transmission Potential (ATP) below 100. Only one point has an ATP of 119 if only the transmission due to the savanna species is considered.
(g) The post-control entomological studies conducted in 1993-1994 show that out of the eight poin6 srudied,lhe rate of infectivity of the parous females is between 0 and 0.57 infective female per 1000 parous, which makes any resumption of transmission unlikely.
(h) The aquatic monitoring activities covered mainly the short-term evaluation of etofenprox or Vectron and that of the long+erm impact of pyraclofos, permethrin and carbosulfan on fishes and the non-target invertebrates. Vectron has proved to be 70 to 200 times less toxic than pennethrin on fishes, six io ten times less toxic on shrimps and 10 to 20 times less toxic on the non-target aqutic insects, still compared to permethrin. For the long-term monitoring, the Ecological Group_ has observed that the increasing impacts of the socioeconomic development of the onchocerciasis-freed valleys on the aquatic environment no longer made it possible to study the possible impact of the larviiiOes used by OCP. It has therefore requested the extension of its terms of reference to the study of the environment of the valleYs.
(i) There has been a progressive increase in the distribution of ivermectin. Close to two tnittion persons living in 700b uill"ges received treatment. The coverage in terms of percentage of treated ieople p"r c"*us population was of the average of 7O%. Delivery of ivermectin through community-self-treatment has been encouraging and is now carried out in five countries in fifteen river basins. The coverage through this delivery is around 75%. APart from three reported cases of hypotension, no further serious adverse reactions were noted during the treatment period' JPC1s.2 Page 5
0) Several non-governmental organizations (NGOs) are now involved in the ivermectin distribution in most of the Participating Countries through large-scale, passive and mobile service distribution, in addition to the community self-treatrnent.
(k) Epidemiological evaluations were carried out in the zones of the original Programme area, where larviciding is the only control measure with a view to evaluating the impact as well as helping in decision-making on the cessation of larviciding in certain river basins. The results, on the whole, were very good in most of the areas evaluated.
(l) In the areas of both larviciding and ivermectin treatment, several villages were evaluated with the view of selecting parasitologically negative individuals who do not receive ivermectin to form a cohort to be followed up to determine the incidence of infection in such areas.
(m) In certain river basins in the original area where larviciding has stopped, epidemiological evaluations were carried out by the national teams in the context of devolution with a view to detecting any possible recrudescence of infection. The results were very good in most situations.
(n) The ophthalmological and parasitological assessment of the medium- and long-term effects of large-scale ivermectin treatment after five years of annual treatment showed satisfactory results. The skin microfilarial load has decreased markedly and there have been appreciable improvements in lesions of the anterior segment of the eye. The overall results show a beneficial effect of ivermectin treatment on the ocular disease in the population.
(o) Migration studies carried out on the Black Volta basin (Bui area) in Ghana showed a higher proportion of the infection in migrants.
(p) As part of the activities of the Biostatistics and Information Systems Unit (BIS), the integrated analysis of the results of the entomological and epidemiological evaluation has been continued, using epidemiological modelling as much as possible. One of the most important results is the analysis of simulations of the combination of vector control and ivermectin distribution which has shown that a period of 12 years is sufficient to reduce the risk of recrudescence to less than 1 %. In order to better prepare the nationals for epidemiologicd analysis, emphasis has been laid on training. During this training, longirudinal data collected during epidemiological surveillance were analysed with them in order to verify any possible recrudescence of infection. BIS has also continued to help the other OCP units in the use of computer science.
(q) Insecticide research has been centred on the comparative use of the different larvicides, monitoring of blackfly susceptibility to the insecticides and quality control of the operational insecticides. With the development of new larvicide evaluation methods, it has been possible to continue research on more effective formulations of B.t. H-14 under better conditions while accelerating the screening of the numerous samples received.
(r) The DNA-probe identification of parasites and the vector identification by morphologicd and morphometric techniques have been continued. The research projects are now focused on the development of DNA probes which could make it possible also to identify the vectors. Many probes have already been developed and will be tested as soon as possible.
(s) It has been recommended that research on macrofilaricides be terminated in 1997. All future work of Macrofil will be focused on compounds already identified as potential clinical trid candidates. Some research will also continue on methods able to detect any development of ivermectin resistance in onchocerciasis treatment. JPCI'.2 Page 6
(t) The devolution unit continues to play its role of adviser and catalyst as regards training, the raising of the awareness of the authorities and the public, epidemiological surveillance and ivermectin treatment of patients, the preparation and update of the devolution plans of the countries, mobilization of resources for the implementation of the plans and operational research. The impact of these activities of the unit is assessed through the devolution activities carried out by the countries themselves and presented in document JPC15.8.
(u) As regards training, the Programme has continued with its usual training policy and awarded 32 fellowships, including eight to women, between August 1993 and July 1994, thereby increasing to 430 the number of nationals of the OCP Participating Countries having benefited from OCP fellowships between 1974 and July 1994. Besides, in-service and field training of OCP and national staff is being continued and mainly concerns the methodology of the epidemiological evaluation of onchocerciasis, ivermectin distribution and post-treatment surveillance, methods of analysis of epidemiological data, different blackfly study and control techniques, data processing and, finally, management.
(v) The Devolution Unit has also defined a number of criteria that could now be used as indicators to assess the capability of the Participating Countries to maintain OCP's achievements, i.e., to detect in time any onchocerciasis recrudescence and control it by means of an appropriate chemotherapy.
(w) The fundamental task of the Administration and Support Services Unit is to support all the OCP units and divisions by managing as rationally as possible and in the best interests of the organization, rhe human, material and financial resources at its disposal. Special emphasis has been laid on staff reduction both in the category of professional staff and in that of the general services in order to maintain administrative costs at the lowest possible level. The 50% devaluation of the CFA franc at the beginnin g of 1994 will have considerable positive effects on the current budget as well as on future ones.
(x) The Programme has pursued its liaison, information and documentation activities and, in particular, has continued to regularly inform the Donors, Participating Countries as well as those outside the Programme area, the scientific community and the general public of its activities'
\MCTOR CONTROL
Climatic conditions
l. In the Programme's eastern zone, the rainy season came quite late compared to the usual was poor. However, the situation returned to normal after the -trr"lrypattern. In May andJune, the rainfall rains in July and August. The overall rainfall in 1993 was therefore similar to that of 1992. The iow and medium waters therefore lasted longer than usual. On the other hand, the rise in water level was quite sudden and the maximum spates in 1993 were above those of 1992. Finally, the flood-subsidence period, which was quite abrupt, also came earlier than in the previous year.
2. In the western zone, the hydrological regime has remained more or less the same as in lgg2. However, in 1993, there was a slight delay in the rise in water levels in C6te d'Ivoire and Mali, with a slightly poorer rainfall in the latter country.
3. In the two zones, the 1994 dry season was very severe. The rains started in May in the southern zones and in June in the northern part of the Programme. IPCI'.2 Page 7
Aircraft fleet and aerial operations
4. The aircraft fleet ranged between 11 helicopters in the 1993 rainy season and five helicopters in the 1994 dry season (March). It was planned to use a maximum of nine larviciding helicopters in the 1994 rainy season because of a better distribution of the guaranteed flight hours and supplementary flight hours.
5. The aerial contract between OCP and the aerial spraying contractor, which will expire at the end of 1995, has been giving the Programme full satisfaction as regards both the q'pe of aircraft used (Hughes 500 D or E) and the pilots and mechanics who are competent and experienced.
6. Following his field visit in 1993, the EAC chairman informed the 14th JPC session of the excellent impression he had as regards the remarkable work done by the aerial spraying contractor and the VCU aerial operation teams. [n 1994, two EAC members also visited the Odienne base and noted, very particularly, the qualiry of the spraying system used, the computer on board for the pilot, the "Global Positioning System" (GPS) which enables pilots to know their exact position and find their bearings even without adequate visibility and, finally, the excellent numagement and maintenance of the helicopters. All the details concerning their mission are in the report of the 15th EAC session.
7. In all, for the period of May 1993 to April 1994, the helicopters made 6,470 flight hours as against 7,714 flight hours in 1992-1993 during the same period, i.e., L,244 flight hours less. This corresponds to a saving of about US$886,000 (see Tables 1 and 2). Likewise, as regards the larvicides, 382,461 litres were sprayed in 1993-1994 as against 500,268 litres in 1992-1993, i.e., L17,825 litres less. Considering the litre price of each larvicide, this amounts to a saving of about US$ 1,100,000 (see Table 3).
8. These substantial savings in flight hours and in larvicides are due partly to the definitive cessation of larviciding on some watercourses (see paragraphs 10, 11 and 12) and partly to highly selective larviciding in areas where residual transmission is likely to occur.
9. Apart from the periods of suspension due to the good entomological results or hydrological conditions, suspensions are also made on basins where the entomological situation is good but where the catches could, however, reach higher levels than before without the establishment of onchocerciasis transmission. This is due to the combination of larviciding with large-scale ivermectin distribution. The drastic decrease in the skin microfilarial load of patients makes it possible therefore to reduce the larvicide sprayings, the risks of blackflies getting infected becoming lesser and lesser. However, one has to remain cautious and resume larviciding as soon as the number of females increases significantly, especially if one or the other of them is parasitized without being infective yet. JPC15.2 Page 8
Table 1: Use of larviciding flight hours from May 1993 to April 1994
Month Helicopter
May 1993 410.9
June 1993 609.3
July 1993 678.7
August 1993 588.1
September 1993 620
October 1993 552.6
November 1993 s83.8
December 1993 573.5
January 1994 540.9
February 1994 588.1
March 1994 505
April 1994 2t8.6 Total 6,469.5
Table 2: Comparison of use of flight hours between May 1992 - April 1993 and May 1993 - April 1994
Year Helicopter (+ Aircraft for 92-93)
1992-1993 7,714
1993-t994 6,469.5
Difference between
t992-t993 and - 1,24.5 t993-1994
i.e., a saving of: $712* x L,244 : $885,728 *$7L2 is thJsupplementary flight hour price, the guaranteed helicopter flight hours being paid as a priority. JPCt5.2 Page 9
Teble 3: Comparison of use of larvicides between May 1992-April 1993 and May 1993-April 1994 (in litres)
Larvicides Year Difference Cost in dollars between 1992- 1992-t993 t993-1994 1993 and 1993- 1994
Abate 58,469.3 72,217 +L3,748.7 +$190,420 ($13.8s/l)
Er 300,641.9 214,339 -86,302.9 -$400,445 ($4.6+19 Carbosulfan 25,599 13,@ -11,954 -$u6,t33 ($20.sell)
Permethrin 2L,751.2 20,193 -l,558.2 -$15,894 ($10.20ll)
Phoxim 37,274.1 18,843 -18,431.1 -$273,702 ($14.8sn)
Iraclofos 56,553.2 43,225 -t3,328.2 -$352,530 ($26.4sn)
Total 500,269.7 382,46t -1L7,825.7 -$1,098,294* * This substantial saving is partly due to the cessation of larviciding on some watercourses and paftly to a more rational use of the larvicides (cf. para. 8 and 9).
Treated areas @g.l)
10. In 1993-1994, in the original Programme area, only the rivers that had been subjected to reinvasion before the south-eastern and south-western extensions were treated. After the cessation of larviciding on the Banifing IV, the whole of the White Bandama, the upper part of the Comoe and of the N'zi and the main course of the White Volta and of the Oti, the definitive cessation of larviciding can be estimated to have covered more than 80% of the original area. ll. The south-eastern extension area has been completely under larviciding since 198E. The south-western extension area was brought under larviciding in 1989 as regards Guinea and 1990 with regard to Sierra Leone. For security reasons, it has not been possible to treat southern and eastern Sierra Leone since 1991, but the forest species which breed there do not migrate and, therefore, do not cause any reinvasion problem in the treated part of Sierra Leone, much less in the rest of the Programme area.
12. The Niger, near Bamako, and some of its tributaries (Fie, Faya, Dylamba) are still under larviciding but it has been solely from the ground since 1 January 1994. This change in strategy has been dictated by budgetary considerations, in view of the likely cessation in 1995 of larviciding on the Baoule and the Bagoe (with the exception of the Kankelaba) in Mali.
Insecticides and control strategy
13. The insecticide rotation, aimed at preventing possible blacldly resistance phenomena and limiting the effects of the larviciding on the non-target fauna, has once again proved its efficacy. JPC15.2 Page 10
14. In the eastern zone, all the insecticides, including Abate, were used to the east of the line separating the Mouhoun and White Volta basins. To the west of this line, Abate was not used while the other organophosphorus compounds were used sparingly. In the western zone, the use of Abate was intentionally increased during this period in order to better assess the limits of its use. Although a slightly reduced susceptibility has been recorded on some basins, this has not had any effect on the transmission.
15. For the past four years, OCP has used the same series of six larvicides, i.e., three organophosphorus compounds (Abate, phoxim and pyraclofos), a biological insecticide G.t. H-14), a pyrethroid (permethrin) and a carbamate (carbosulfan). Compared to 1992, the general insecticide use trends observed in 1993 for the whole Programme area have been a decrease for B.t. H-14, carbosulfan and phoxim, and an increase for Abate; besides, the use of pyraclofos and permethrin has been stable. The decrease in the use of B.t. H-14 in the two operational zones was due to the re- establishment of the normal dose (which was increased in 1992 because of defective batches) and the more intensive use of Abate at low river discharges. The decreased use of phoxim was due to the shortage of the stocks in the western zone. As regards carbosulfan, the reduction is related to the low rainfall in the eastern zone and to a general increase in the use of Abate at high discharges.
16. By authorizing the use of Vectron, the Ecological Group has put at the Programme's disposal a seventh insecticide which will be used in June on some basins where Abate is not recommended, particularly in C6te d'lvoire, on the Comoe and the lower Bandama and, to a lesser extent, on the Marahoue and the Sassandra.
17. There have been no problems with the quality of the operational insecticides in 1993-1994. Most of the screening efforts have been centred on the operational batches of B.t. H-14. Because of the production procedure (fermentation), successive batches of B.t. H-14 are likely to vary and therefore necessitate a closer monitoring. The quality control procedure has been simplified as a result of the development of an orbital shaker bioassay system and the installation of a mobile laboratory at the IRU (Insecticide Research Unit) field station at Soubre. Since June 1993, the bioassays have therefore been undertaken under controlled conditions (temperature, water quality, etc.) and the results show a better coherence during repetitions of the trials. The B.t. H-14 batches (Vectobac l2AS) sent by Abbott in 1993-1994 were good in terms of the physical characteristics and efficacy as well as the test samples and their operational batches.
18. In the whole Programme area, the week of 6 to 11 September 1993 (week 36193) recorded the highest larviciding coverage with I 1,575 km of river treated, mobilizing the I I helicopters under contract and using all the insecticides then available (Vectron was not yet operational). On the other hand, the week of 28 March to 2 April 1994 (week 13194) experienced the lowest larvicide coverage with three larviciding helicopters and3,77O km of river treated, a complete cessation of larviciding in the eastern zone and the use, in the west, of only three insecticides, i.e., a biological-origin insecticide (Vectobac) and two organophosphorus compounds (Abate and pyraclofos).
19. No operational failure of larvicides was noted in 1993-1994 in connection with the resistance problems. Only a few badty targeted aerial sprayings had to be supplemented by ground larviciding to improve the entomological situation on some reaches, particularly during the changes in season (passage from the dry season with the use of B.t. H-14 to the rainy season with the use of chemical insecticides or conversely).
Hydrology and teletransmission
20. The rapid obtention of reliable hydrological data is necessary for an accurate dosage of the different insecticides in all of the Programme's treated areas. Jrc15.2 Page 11
2L. Accordingly, OCP has repaired or established the hydrological network of the various Participating Countries. At present,22O hydrological stations are continually monitored. The main ones, 102 in all, are equipped with Argos beacons which regularly transmit the discharge variations by satellite. Two reception stations located near the aerial bases in Odienne (COte d'Ivoiie) and Ihra (Togo) receive, each day, six to seven satellite passages four ofwhich cover all the beacons used by the Programme.
22. By using the discharge forecasting software, PERLES, developed by the French Institute of Scientif,rc Research for Development through Cooperation (ORSTOM), calculation of the dosages of the different insecticides is made immediately for all the reaches treated and these dosages can Ue adjusted continuously through radio contact with the various larviciding helicopters. The result is an optimization of the larviciding circuits and a more rational field organization of the aircraft fuel caches and the treatment larviciding caches.
Sureillance and entomological evaluation network
23. In the original Programme area, the entomological evaluation network is reduced or removed when post-control entomological srudies are completed after the definitive cessation of larviciding. Thus, the Bougouni subsector was closed down at the end of 1989, the Bandiagara station at the end of 1990, the Niamey and Sikasso subsectors at the end of 1991 and that of Natitingou on 30 June 1992. The Ouagadougou, Bolgatanga and Korhogo subsectors were closed down at the end of 1993. On the whole network, in two years, the number of regular catching points has decreased from 140 to 128 as regards the dry season and from 266 to 2L2 withregard to the rainy season.
24. Three significant facts deserve to be underscored:
(a) All the entomology technicians have received an intensive training as part of the morphological identification of S. damnosum s.l. females. This technique is at present applied every week for identifying dissected blackflies. The results are used in the preparation of ATP maps.
(b) Since November 1993, the ATPs have been calculated on a weekly basis and not monthly as in previous years. This new method of calculation gives results closer to the reality.
(c) All the infective larvae sampled during dissections are collected and sent to the DNA- probe laboratory in Bouake for identification. The results are used for correcting the ATps, eliminating animal-origin infective larvae (mainly O. ochenei). The ATP maps, attached hereto as annexes (Fig.2, 3 and 4), cover the period of June 1993 to May 1994.
Entomological activities of nationd teams in the south-westem extension area
25. The exclusive use of ivermectin (MectizanR; in the northern part of the western extension has led to the suspension of entomological surveillance activities in thai part of the programme area and to the closure of four bases in western Mali, one base in Senegal and two bases in Middle Guinea. The remaining bases in this northern part are used for ivermectin treatment campaigns.
26. In Guinea and Sierra Leone, there have been no major changes in the entomological surveillance network in 1993-1994, except the closure of the Bo base in southern Sierra Leone. At present, it comprises 1l operational bases made up of 32 catchingdissection tearui and technicians responsible for taxonomic, hydrological and hydrobiological srudies. The number points of catching -Sierra monitored regularly has decreased from 78 to 62 in view of the cessation of larviciding in Leone for security reasons. These national teams comprise 158 persons in Guinea and 66 in Sierra Leone. In Mali, 12 workers took part in the post-control studies. JPC15.2 Page 12
Results obtained
Transmission (Fig. 2, 3 and 4)
27. Figure 2, attached hereto as an annex, gives the ATPs of species of the S.damnosum complex infected with Onchocerca s.p. The comparison of Figures 2 and 3 shows that most of the infective blackflies caught on the Baoule, the Keran, the Mo, the Alibori and the Sota are infected with animal Onchocerca. Figure 3 which concerrrs only the ATPs calculated on the basis of the infective larvae of O. volvulus has been established by taking into account the results of the DNA- probe identifications.
28. On the whole, the results concerning the transmission for the period of June 1993 to May 1994 are quite satisfactory. Out of the 212 catching points monitored regularly, 92% have an ATP below 100 and oriy 8Vo an ATP above 100, if the transmission due to all the species of the S.damnosum complex is considered. Finally, Figure 4 concerning the ATPs due to savanna species of the S.damnosum complex infected with O. volvulus indicates that, in the whole Programrne area, only one point out of the 212 has an ATP above 100. This concerns Landa-Pozanda, near Kara, in Togo, where the ATP is 119. However, all the infective larvae collected at thatpointhave not yet been identified by DNA probes.
29. In conclusion, the residual transmission of O. volwlus by the savanna species of the S. damnosum complex has been maintained at a negligible level (for 1993, the weekly mean in the whole Programme was six infective females containing 14 infective larvae of O.volvulus).
1993-1994 post-control entomological studies
30. These studies are aimed at checking whether the infectivity rate of blackflies which resettle after the cessation of larviciding is sufficiently low to prevent transmission recrudescence. Using the mathematical model, it has been shown that with an infectivity threshold below one infective female per 1,000 parous, the risk of transmission recrudescence is negligible and even nil. For the results io be statiJtically reliable, a minimum of 15,000 parous females have to be dissected and the study conducted for two consecutive years if necessary.
31. With a view to decision-making on the definitive cessation of larviciding, post-control studies have been carried out in 1993-1994 on the Banifing IV, the Black Volta, the White Volta, the Oti, the Pendjari, the Leraba and the White Bandama (Fig.5).
32. On the Banifing IV, the special post-control study carried out from October to December 1993 during the period of transmission on four points (Konina catching point, Konina larval breeding site, Kouo and Kouoro-ford) has made it possible to collect infective larvae which have been identified by DNA probes. Out of the 19,560 parous females dissected, 240 infective females were detected. The identification of the infective larvae showed that they were all from animal Onchocerca.
33. At Chache on the Black Volta, no infective female was detected out of 1,270 parous females. The results obtained on the other points where the studies are in progress are excellent. The number of infective females per 1,000 parous is as follows: Sugu (White Volta) 0.14; Oti-Tontionga (Oti) 0.14; Bukasu (Oti) 0.54; Porga (Pendjari) 0.49; Pont-Leraba (Leraba) 0.51; Niaka (White Bandama) 0.57. tt should be specified that at Porga, 62Vo of the infective larvae are animal Onchocerca.
34. In 1995, it is planned to carry out post-control studies at Madina-Diassa and N'Zana on the Baoule and at Metela on the Bagoe. JPC15.2 Page 13
Monitoring of the aouatic environment
previous 35. As in years, the greater part of the aquatic monitoring activities have been carried o1t-by the national hydrobiology teams of the Participating Countries under service contracts signed with the Programme. The OCP Aquatic Monitoring Oivision coordinates all the activities anA-Aso conducts some toxicity tests on the organisms.
36. The monitoring was centred mainly on the short-term evaluation of the toxicity of etofenprox (OMS 3002 or Vectron) and on that of the long-term impact of pyraclofos, permethrin and carbosulfan on fishes and the non-target invertebrates.
37. Etofenprox (OMS 3002 or Vectron) has presented a short-term toxicity on the non-target insects which is comparable to that of pyraclofos, an insecticide used at discharges above 15 mis. Furthermore, it is 70 to 200 times less toxic to the fishes and six ro ten times leis toxic to shrimps (Cetidina. sp) than permethrin. The Ecological Group has therefore considered etofenpro* to 6, sufficiently selective with regard to the non-target aquatic fauna to be used on a large scale by the Programme. However, it expressed the wish for further information on the medium-term impact of the product on the non-target fauna to be available at its next session.
38. The long+erm monitoring data have not indicated a significant and irreversible impact of the use of permethrin, carbosulfan and pyraclofos on the non-target fauna. The inseits are experiencing a decrease in density and a change in the strucrure of the communities both of which are within acceptable limits. [n some watercourses which are no longer being treated, these changes are continuing, which suggests the influence of factors other than the antiblackfly larvicides (inlustrial or agricultural pollutions, various human activities, etc.). As regards the fishes, the decrease in catches has been going on since the 1980s on nuny watercourses monitored (treated or not). However, the coefficient of condition of the principal species is still almost stable, which indicates that it is not the lack of food which is the cause of this situation. The drought, overfishing and destruction of gallery forests could be the cause.
39 . These impacts being more and more considerable because of the socioeconomic development activities in the onchocerciasis-freed valleys, the Ecological Group has considered that it was now difficult for it to work without an extension of its mandate.
TVERMECTIN (I\,IECTIZANR) DISTRIBUTION AT'[D EPIDEMIoLoGICAL AcTtvITIEs
Ivermectin trrcafuent
40. [vermectin distribution was carried out its in the previous years in the OCp by national teams supported financially and logistically by the Programme. ln Guinea, Mali and Sieira Leone, addd support, in the form of funds, was provided to the national teams through non-governmental organizations (NGOs) for distribution in clearly defined areas. The treatrnent ilas canied out on the basis of the strategy of distribution defined beforehand, which is to give priority treatment through large-scale distribution to dl areas of high risk of onchocercal eye disease and./or blindn rr, i.e., arcas with CMFL! of 10 mf/s2 or more. The areas concerned are in the southern extension (Benin, C6te d'Ivoire, Ghana and Togo) and the southern part of the western extension, (Guinea and Sierra l*onc). In the northern portion of the western extension, in the area north of the Tinkisso river basin where
TCMFL: Mean community microfilarial load
2 mf/s: Microfilariae per skin snip JPCl5.2 Page 14 there is no larviciding and ivermectin use is the only means of control, the CMFL at and above which large-scale ivermectin treatment is given has been set at 5 mf/s. Large-scale ivermectin distribution was also carried out in certain parts of the original Programme area. As specified in document JPCI5.8, this was in well defined and specific areas where the entomo-epidemiological results have not been fully satisfactory. These areas are: the Kulpawn/Sissili, Mole and Black Volta basins in Ghana, the Dienkoa basin in Burkina Faso, the previously reinvaded zones - Bagoe, Kankelaba (Mali), Sota, Koumoungou (Benin), Kara-Keran-Md (Togo) - as well as the intermediate zones in C6te d'lvoire. A small area on the Baoule basin (COte d'Ivoire), an area of previous reinvasion was also placed on ivermectin treatment. (Fig.6).
41. The main mode of distribution was through the large-scale method carried out entirely by the national onchocerciasis teams. This accounted for around 70% of the total distribution. Another mode of distribution was the community self-treatment which, although a form of large-scale treatment, is operationally different in terms of logistics, finance and the personnel involved. (See doc. JPC 15.8). It accounted for 24% of the distribution. Additionally, there was a small amount (6%) of treatment through other modes of distribution.
42. Several NGOs are involved in or plan to take part in the ivermectin distribution in the OCP area (Table 4). The NGOs work in well demarcated and specific river basins, making full use of the epidemiological mapping prepared by OCP and in collaboration with the National Onchocerciasis Coordinator and his team.
Table 4. NGOs involved in ivermectin distribution in the OCP area - 1993194
ORGANIZATION COUNTRY MODE OF TREATMENT BMRC Sierra Leone Large-scale treatment CBM (Lunsar) Sierra Leone Large-scale treatment
CFAR Mali Community self-treatment
OPC Senegal Community self-treatment Mali
PhilAfricaine Suisse Guinea Passive
Sight Savers Sierra Leone, Mali Community self-treatment Ghana, Guinea
Trop. Inst. Germany Benin, Togo Passive
Number of people treated with the support of/or by the Non-Governmental Organizations: about 700,000
BMRC: British Medical Research Council CBM : Christoffel Blindenmission OPC : Organisation pour la pr6vention de la c6cit6 CFAR: Centre de formation d'animatrices rurales.
43. During the period in question, close to two million people were treated with ivermectin through the various modes of distribution in over 7000 villages. Most of these villages are in the extension areas. The average coverage, i.e., number of people treated divided by the total census population, through large-scale distribution by the national oncho teams was 7O% . The coverage has IPCt'.2 Page 15 consistently been higher in the previously high endemicity areas as compared to the low endemiciry areas. The distribution through the community self-treatment ensures a much higher coverage, 75To (Fig.7). This high coverage from the community self+reatment is due to the fact that treatment is available all the time in the village. Thus, individuals who might have been excluded from treatment for some reason, and become eligible later, receive their treatment without having to wait until the following year.
4. Monitoring for adverse reactions was carried out, for 36 hours after each treatment, by the tearns carrying out ivermectin distribution. Although only severe adverse reactions are recorded, any side-effects that require treatment are also noted. Each team undertaking large-scale distribution has a drug monitoring kit to undertake treatment of any severe adverse reactions, should this be necessary. Several tearns are supervised by a medical officer during the distribution period. In the case of community self-treatment, the occurrence of any adverse reaction is reported to the nearest health centre. Three cases of hypotension were recorded and managed by the treatment team in Sierra Leone. These cases were said to be new entrants (people who never received ivermectin) into the treatment villages from the areas of rebel action. Minor side-effects, like headaches, dizziness and mild itchiness, needed no special treatment. There has been no problem with drug accessibility to the communities in the areas of operation.
45. Three basins where ivermectin treatment has been carried out for five years or more were evaluated with special attention to the occurrence of infections in children of five years old or below. These are children excluded from ivermectin treatment. In the Gambia basin where ivermectin has been given biannually without larviciding and in the Niger basin where there has been annual ivermectin treatment and larviciding, there were no infections in the children five years old or below. In the Black Volta basin (Bui area), however, an area of both larviciding and ivermectin treatment, several children of five years old or below were found to be infected in a village south of the treatment area and could possibly be infection with the forest strain of O.volwlus.
46. Villages have been selected at random to constitute an in vivo sunreillance network for the detection of any lowered microfilarial susceptibility to long+erm ivermectin treatment. In this respect, rwo villages that were evaluated in Guinea showed no evidence of lowered microfilarial susceptibility.
EPidemiological evalpation
47 Epidemiological evaluations were carried out in the OCP area with the help of the national onchocerciasis teams and as before with the following objectives:
- to help decide on stopping larviciding in specif,rc river basins in the original OCP area where no other form of control apart from larviciding had been used;
- to assess the impact of the control activities through the measure of incidence in the western and southern extension areas and other specific areas in the original area which are subjected to both ivermectin distribution and larviciding.
Evaluation of villases in areas where only larvicidine is undertaken
48. In the original Programme area, epidemiological evaluations were carried out in six basins to help with the decision as to whether larviciding could be stopped: the Alibori and Mekrou in Benin, the Daka in Ghana, the Comoe and the N'zi/Bandama in C6te d'Ivoire and the Bagoe in Mali and in C6te d'Ivoire. JPC15.2 Page 16
49. In all these basins, indicator villages, i.e., first-line villages which have had several evaluations in the past, were examined. The classic parasitological method of skin snipping was used to assess the prevalence of infection, the intensity of infection and the presence of any new infections. New infections :ue defined as infections in children born after vector control started in the area or infections found in individuals who are known to have been previously parasitologically negative on two consecutive occasions. Figures 8 and 9 give a general picrure of the prevalence of skin microfilariae before the start of the control operations compared with that revealed by the epidemiological situation updated in 1993- I 994.
50. The results from two villages in Mali and two in C0te d'Ivoire in the Bagoe basin were very good to excellent. The highest prevalence and CMFL were 4.6Vo and 0.12 microfilaria per skin snip (mf/s) respectively. The observed prevalence trend in the village of Galamankourou on the Bagoe followed closely the predicted version, but showing some delay as from l0 years of vector control (Fig.lOa).
51. The results obtained from the four villages evaluated in the N'zi/Bandama basin were excellent. The highest unstandardized prevalence was 2.15%. No new infections were found.
52. Four villages were evaluated in the Comoe basin. The results were excellent in all the villages with respect to the unstandardized prevalence. The highest prevalence wu 3.9%. However, in the village of Awahikro, two children below 15 years of age were found to be infected. One of them had a history of migration. The second, aged nine, had never left the village.
53. The result from Gbeniki village in the Mekrou basin was satisfactory: prevalence of 5.7% and CMFL of 0.12 mfis. At the last evaluation (1989), the prevalence was L2.LVo and the CMFL 0.66 mfis. The observed prevalence trends showed a continued decline but had a delay of three years compared to the predictions of the epidemiological model (Fig'10b).
54. The results from the two villages evaluated on the Alibori were unsatisfactory. The prevalence was 13.l% at Lougou and 20.47o at Alibori village. In both cases, the CMFL was 0.48 mf/s. Although the observed prevalence trends in the village of Lougou were unsatisfactory, they were encouraging and had started to decrease (Fig.l0c).
55. In the Daka basin, five villages were evaluated. The prevalence ranged between 0.0% at Papala and L9.8% at Ekumdipe village. In the latter village, 60% of the positives were migrants from the Pru basin and 207o migrants from Tantali, a village on the Oti.
Evaluation in the areas of both larvicidine and ivermectin distribution
56. In the areas where both larviciding and ivermectin treatment are applied, the parameters of prevalence and intensity of infection as previously used to assess the impact of vector control in the original Programme area, where no ivermectin was applied, are no longer valid. In such situations where the effect of ivermectin treatment would mask results, the use of the incidence of infection, i.e., new proven cases, becomes the method of choice for assessing the impact of the control measures on transmission.
57. Evaluations have been undertaken in 24 villages in basins in Guinea, and Sierra Leone (western extension). The parasitologically negative individuals (individuals shown to be negative on two consecutive occasions) in these villages will constiilte a cohort of individuals for follow-up in respect to incidence of infection. Such individuals will not receive ivermectin treatment in the course of the annual ivermectin distributioncampaigns. However, any such individuals who are subsequently found to be parasitologically positive will be placed on ivermectin treatment; in such cases, the treated individuals will be removed from the cohort being followed up. The cohorts include both adults and JPC15.2 Page 17
children. By virrue of its nature, results for this type of evaluation will only become available after several series of surveys.
Migration studies
f8. Migration questionnaires were completed as part of all the epidemiological evaluations. However an in-depth migration study was carried out on the Black Volta basin (Bui area) in Ghana w!!9n in l0 villages were involved. Of the 193 individuals found parasitologically positive, 90 919.0%) were migrants that had come from further south of the country. This may tuggeit infections of the forest type of O.volvulus.
OPhthalm elogical evaluations
59. Ophthalmological evaluations were carried out in two follow-up villages in the Milo basin in Guinea. These were evaluations undertaken after five years of annual ivermectin treatment in these villages. The present results were compared to the base-line data and data obtained one year into the annual ivermectin treatment, in order to determine the medium-term evolution of ocular onchocerciasis.
60. After five years, the microfilarial load in the anterior chamber of the eye had reduced significantly. Living microfilariae had disappeared from the cornea and the arithmetic mean of microfilariae in the anterior chamber had reduced from 6.61 to 0.05, while noting that it takes l0 years of vector control to observe similar results. It must, however, be emphasized that the area under study has a combined ivermectin and larvicide application.
61. With respect to the evolution of eye lesions of the anterior segment, there was a slight improvement in early and advanced iridocyclitis as well as sclerosing keratitis one year after ivermectin treatment as compared to the baseline data. Five years after annual treitments, a stabilization of lesions of sclerokeratitis and disappearance of early lesions with stabilization of advanced iridocyclitis were observed. With regard to the evolution of ocular lesions of the posterior segment, there was stabilization of the lesion. Thus, the overall results compare favourably to those that have been obtained from the Asubende focus in Ghana where a cohort of individuals have had regular ivermectin treatment and ophthalmological follow-up.
BIOSTATISTICS AND INFORMATION SYSTEMS
62- During the period under consideration, the Biostatistics and Information Systems Unit (BIS) has continued to carry out the processing of the entomological and epidemiological evaluation data, particularly supervision of the data entry and validation made by the VCU and-Epl teams. The unit has also played a major role in computer assistance in the Programme. This assistance concenut training, management of the different data banks and their baclorp, and the maintenance of the different computer equipment installed in OCP.
63. To standardize the different data banls in order to make rhe users more independent when using them, programming has remained an important activity in BIS. The preparation of aids which will make possible data collection and analysis during devolution has been continued with the development of the data bank for the countries. The use of this software package called SEpT was startd with a sentinel village data entry and validation phase in the EPI Unit. This computer progralnme will enable the epidemiologists of the Participating Countries to exchange later with OCp the results obtained and to make routine analysis of the data after each evaluation irorder to compare the results with the existing data. To make this work easier, emphasis continues to be laid on the verification and general update of the epidemiological data. The unit is actively planning with the devolution unit the transfer of the data to the Participating Countries. An attempt will be made very JPC15.2 Page 18 soon to transfer data to Niger and C6te d'Ivoire where workers will be trained by OCP for data processing. The transfer to the other countries will follow as and when they are equipped with adequate computer equipment.
U. This year has also been devoted to the development of a reference data bank on the control of the vector in OCP. Firstly, a routine entomological evaluation data bank has been developed, which makes it possible to study the trend of the usual entomological indices such as the Annual Biting Rate (ABR) and the Annual Transmission Potential (ATP). When completed, this bank will be as flexible to use as that for the epidemiological data and could be made available to the Participating Countries for consultation of the historical entomological data collected during vector control. The other existing data such as the aerial operations data on insecticide use, hydrology, cytotil(onomic data on the identification of the aquatic larvae of Simulium damnosum s.1., morphometric data and other relevant information such as the data on the monitoring of the aquatic environment during vector control will be integrated later into this bank.
65. Since the introductionof two computer-based mapping software in OCP, viz., "Cartes et Bases" and Map-Info, considerable progress has been made. A computer with a graphics tablet has been installed in the office of the cartographer who has been trained in the use of basic software like DOS and Windows. This training has enabled him to tackle the use of the Map-Info software serenely. Thus, rivers in the Programme area have been digitized as well as the larviciding reaches, country borders, limits of the different operational phases and main towns. Since the Map-lnfo softwaie has the possibility of projecting on a map the catching points and epidemiological evaluation villages with the geographical coordinates, the Prograrnme maps can be represented automatically and printed in A4 formai. figure 1l shows the location of the catching points of the OCP entomological evaluation network. The spatial analysis of the data is thereby made easier by the gradual introduction of the geographical information system (GIS). The data could be displayed not only for the OCP area as a whole but also in detail at the country level.
66. Routine analyses have been continued in the Unit. Thus, the analysis of the ophthalmological data, those of the epidemiological shrdies on ivermectin and those collected during the srudy onhigrants has been made in collaboration with the EPI Unit. The epidemiological trends observed before the end of vector control in the reinvaded area to the east of the Mekrou and the Alibori, just as to the west on the Bagoe and the Niger have been reviewed. As part of the ophthalmtlogical monitoring of the impact of ivermectin on morbidity, the data collected in the ,ill.g., on the Milo in Guinea have been analysed. These data have shown the same trends observed at Aiubende in Ghana for the ocular lesions. More generally speaking, the epidemiological data have made it possible not only to show that the predicted trends are in conformity with those observed but also to validate the quantification of epidemiological modelling Parameters.
INTERDISCPLINARY RESEARCH
Insecticides
67 . The obtention of etofenprox has made available to OCP a choice of six chemical insecticides for larviciding. These insecticides belong to three groups of insecticides (organophosphorus cornpounds, carbamates and pyrethroids/pseudo-pyrethoids) and make it possible to treat the whole rangl of river discharges. OCP should therefore be able to apply the rotation strategy without any major constraint and to face any possible resistance. It has therefore been decided to reorientate the activities of the Insecticide Reseaich Unit (IRU) which will now give priority to the development of larvicide evaluation methods and the development of biological insecticides.
68. This year, IRU has continued with the research on the development of new larvicide evaluation methods. The evaluation of antiblackfly larvicides has been based so far on the system of JPCrs.2 Page 19 troughs for the chemical insecticides and on the system of mini-gutters for the evaluation of the B.t. H-14 formulations. These two systems have great limits and are prone to great variations in results. They have the shortcoming of taking place outside and therefore of giving results which vary according to the ambient temperarure conditions and river water quality. IRU has therefore devoted its efforts to the development of closed-circuit bioassay systems and a mobile laboratory equipped with an air-conditioner has been installed at Soubre.
69. A new system, using an orbital shaker, has been developed in collaboration with the company Abbott in order to replace the mini-gutter system. The test protocol developed by IRU is now operational and the tests on the Simulium damnosum larvae give results equivalent to those of the mini-gutter system under average conditions. The shaker system should therefore give a correct estirnation of the efficacy of the B.t. H-14 formulations in river. Apart from the quality control, this system is commonly used for the evaluation of experimental formulations prepared by Abbott as part of a Vectobac formulation improvement project.
70. Despite the availability of the shaker system, there is still the need for a system that will make possible the evaluation of chemical insecticides as well as B.t. H-14 on both the non-target aquaric insects and the blackflies. IRU has therefore developed a multi-agitator system through the improvement of a system proposed by M.H. Colbo in L977. This system can be used not only for g.i. H-ta (with the same prorocol as that of the shaker), but also for the chemical insecticides by changing the water after the exposure to the larvae. The first trials on the Trichoptera larvae with chemical insecticides have been conclusive and definitive protocols will be prepared in the course of the year.
71. The collaboration between OCP and "Institut Pasteur de Paris" has been continued with a view to the evaluation of recombinant strairs of B.t. H-14 as well as new strains of Bacillus. The trial of recombinant strains is aimed at determining the relative toxicity of the different B.t. H-14 toxins. The new strains of Bacillus are of interest since they have never been tested on blackflies and because their toxins are different from those of B.t. H-14. With the new bioassay systems, the screening of these bacteria will be accelerated in 1994-1995.
72. IRU has also continued this year with the monitoring of blacldly susceptibility to the insecticides, particularly Abate. Among the chemical insecticides used by OCP, Abate has distinguished itself by its advantages from the operational and environmentd viewpoints; it is therefore of the utmost importance to identify the zones of resistance or of risk of resistance to Abate, in order to maximize its use in the rest of the Programme area. The susceptibility to Abate has gradually improved in recent years through the application of the insecticide rotation strategy. Consequently, the use of this insecticide has increased in 1993/1994 compared to 199211993 (See Table 3), which has resulted in substantial savings in the operations while ensuring good entomological results. The latest susceptibility data show, however, that the tolerance of Abate, notably in S. damnosum s.s., has increased at many poins in the Prograrnme area, particularly in the eastern and central parts. As a result, the rotation strategy will be modified for some hydrologicd basins in 1994-1995.
73. Phoxim resistance is limited to the usual foci in southern C6te d'ivoire (lower Bandarna, lower Comoe). It concerns only the local populatiors of Simulium sanctipauli s.s., and the latest data show a regression of the resistance levels compared with the initial levels of 1980-1985. Phoxim is therefore effective everywhere, except in the resistance foci, but with caution in a buffer zone which includes the Maratroue, the N'zi and the lower Black Volta.
74. Despite is generalized use in the Programme area, the efficacy of pyraclofos has not yet been affected by the problem of resistance. Only one case of resistance was detected in 1991 on the Marahoue, in the exceptional context of 16 consecutive weekly applications; the resistant populations JPC15.2 Page 20 were controlled through alternative insecticides and the susceptibility returned to normal. The recent data show a good susceptibility to pyraclofos everywhere, even in the populations resistant to Abate or phoxim.
75. Permethrin and carbosulfan are used restrictedly in the OCP operatioru; because of ecological reasons. Except for some rivers (Niger, lower Bandama), they are used only for a few weeks (generally two to three) on the principal reaches. The monitoring of the susceptibility to these insecticides is therefore aimed at detecting resistances due to external factors (agricultural use). In the OCP-treated area, no resistance to these insecticides has been detected yet; on the other hand, blackllies tolerant to permethrin have been found on the Bagoe, this phenomenon being probably related to an agriculrural use of the product. The baseline data show that the susceptibility to etofenprox is uniform throughout the Programme area and no resistance problem is foreseen for this insecticide.
Vector and parasite identification
76. Most of the entomological research projects initiated in recent years have been completed and the results have been or will be published soon. The subjects covered are mainly the description of the species of the S. damnosum complex, the determination of their area of distribution and the study of rheir vectorial capability under experimental conditions. The activities of the AREM teams in Bamako, Odienne, Kara and Bouake have been focussed on the development of more precise identification methods for the identification of samples collected as part of the VCU entomological surveillance network. The VCU technicians have all been trained in these methods and a training monitoring prograrnme has been prepared. These research and training efforts have improved the quality of the operational data which are now utilizable for research purposes.
Vector identification
77. Cytotaxonomy is still commonly used for the identification of blackfly larval populations. The results obtained in 1993-1994 confirm the previous data on distribution and seasonal abundance. Samples from susceptibility tests are routinely identified cytotixonomically, which gives a detailed picrure of the susceptibility of the different blackfly species and populations to the operational insecticides.
78. The new adult female identification methods, which use simple and reliable morphological and morphometric criteria, are corlmonly applied by all the AREM teams. The identifications made through ihese methods give, together with the cytotaxonomic data, a much more reliable and detailed description of species fluctuations among the adult blackfty populations. Through morphological identification, ii has been possible to monitor accurately the periods of alternation of savanna and forest blackfly populations in the river basins of the western zone. With morphometry, it has even been possible to monitor individually in the Sassandra and Baoule basins the seasonal abundances of S. sirbanum and S. damnosum s.s. whose adult females were previously indistinguishable.
79. Electrophoresis is still used for the identification of adult females, but particularly as part of the verification of identifications made by the new methods. To date, the data show a good correlation between the identifications made by these different techniques.
Parasite identification by the DNA-probe technique
80. Using the DNA-probe technique, the Bouake laboratory has been maintaining its performance with regard to the identification of parasites collected in the Progralnme area' The prime use of the identification results is the correction of the ATPs by the elimination in the calculations of JPC15.2 Page 2L the number of parasites not belonging to the Onchocerca volvulus species. The identifications made in Bouake have, thus, made a significant contribution to the vector control strategy and management.
81. The collaboration with the University of Alabama is continuing and considerable progress has been made on many projects. It is now possible to detect one parasite in a crushed masi oi tOO blackflies; this technique will make it possible to detect very low levels of infection from batches of blackfly heads or full blackflies crushed. A new probe revelation ELISA sysrem has also been developed; this system will increase the identification capacity of the Bouake laboratory and reduce the cost of reagents. Finally, a DNA-probe blacHly identification sysrem has been developed; five of the main species of the S.damnosum complex are already identifiable ar one stage. Thii system will be of value for the identification of infective females and therefore for the determination of the parasite-vector associations under narural conditions. Since the beginning of the activities of the Bouake laboratory, the abdomens of infective females have been conserved at the sarne time as the parasites; OCP therefore has a considerable quantity of specimens ready to be identified. The research projects are now focussed on the development of more effective probes for the identification of the savanna form of O. volvulus and on the use of DNA probes in epidemiological surveillance.
Epidemiologrcal modelling
82. The ONCHOSIM model has been used in collaboration with the department of public health of Erasmus University, Rotterdam (Netherlands), to refine the quantification of the parameters related to the action of ivermectin and to determine the optimal duration of a strategy based on the combination of vector control and ivermectin distribution. It is known that a single ivermectin treatment causes the elimination of skin microfilariae but that after some time the microfilarial density starts to increase again. Irreversible effects have also been observed previously on the fecundity of adult O.volvulus after repeated treatments at very short intervals. This year, the field data collected have made it possible to check whether there are irreversible effects on the adult parasites when ivermectin is administered annually as part of a large-scale distribution. The methodology used is based on the skin-snip microfilarial counts of 114 aduls selected in a hyperendemic zone at Asubende, Ghana, by including also in the analysis the effect of the vector control carried out at the sirme time as the ivermectin treatment. The assumptions on ivermectin have been tested by comparing the model predictions with the post-control data collected on these persons during the first five years of trial.
83. The model has shown that the trend of the microfilarial counts can be explained only if it is admitted that the treatment causes not only a temporary decrease in microfilarial production but also affects the fecundiry of the wonns irreversibly. Two tlpes of irreversible effect which also explain the trend well are: (1) a permanent reduction (2640%) of the productivity of all the wonns; or (2) the total loss of fecundiry of a proportion(22-35%) of the worms. Therefore, after each ivermectin treatrnent, the worms recover during a period of 10 to 11 months and reach a new stable level of microfilarial production which is 30% less than the pre-treatment one. This irreversible effect has favourable implications on the cost-effectiveness of the onchocerciasis control strategies based on an annual ivermectin treatrnent.
84. On the basis of these new assumptions, the simulations made with the epidemiological modelling have shown the same observed and predicted frequency distributions of microfilarial counts for the pre-control survey and post-control surveys for the cohort of aduls aged more than 20 years having received the five ivermectin treatments and having participated regularly in eight parasitological examinations (n : 78). The observations on the cohort of adults aged more than 20 years having received the frrst treatment but absent from the second treatrnent and who were examined 24 months after the first treatment (n = 36) seem also to confirm the assumption of an irreversible effect of ivermectin on the productivity of the adult worms. JPC15.2 Page 22
85. The ONCHOSIM model has therefore been used to determine the duration of the optimal strategy of a combination of vector control and an annual ivermectin treatment which would reduce the risk of recrudescence to less than I%. The estimation has been made using the logistic regression technique. The basic variables used in the simulations are:
duration of vector control; duration of annual ivermectin treatment; treatment coverage; interval between the start of vector control and the beginning of ivermectin treatment; period of overlap of vector control and ivermectin treatment.
The different epidemiological situations simulated are:
- a standard model with a pre-control CMFL of about 60 mfib; - a less permanent effect of ivermectin (decrease of 25% of the productivity of the worm).
86. Figure 12 gives the results of the simulations. The lines rePresent combinations of vector control and ivermectin treatment which lead to a recrudescence in t% of. cases. Above the lines, the risk is reduced; below the lines the risk is higher. The sudden changes in the direction of the lines concern combinations for which the duration of vector control is equal to the duration of ivermectin treatment. The graphs show that the optimal situation corresponds to a strategy based on 12 years of combination of vector control and annual ivermectin treatment at an average coverage of 65%. This strategy reduces the risk of recrudescence of infection to less than 17o avan in the case in which a reduced perrnanent effect of ivermectin is assumed'
Immunodiaguosis
87. During the last meeting of the TDR Steering Committee on Filariasis, a subcommittee on immunodiagnosis for onchocerciasis met in March 1993. It was concluded that the encouraging results obtained on the tests made using the tri-cocktail antigens (Ov7, Ovl1 and Ov16) for the early detection of onchocercal infections justify the operational organization of the trial of these antigens on a large scale. It has been decided that such tests should be carried out in OCP; this has led to the successful establishment of an immunodiagnosis laboratory in Bouake, COte d'Ivoire'
88. Some 2000 samples on filter-paper have been collected and tested on children aged five to fifteen years in onchocerciasis-freed villages in Burkina Faso and about 200 samples from children in hyperendemic villages in Sierra Leone. The samples have been tested using the ELISA method in Bouake and the Swiss Tropical Instirute in Basle.
89. From these pilot srudies carried out in OCP, it can be concluded that:
(a) the filter-paper blood samples could replace the serum sample by taking care of the storage and desPatch of sPecimens;
(b) the Bouake serological laboratory is effective and operational;
(c) it is necessary to modify the original ELISA test protocol in order to guarantee a better precision and a great reproducibility;
(d) other means of research should be explored in order to explain the relation between serological results and the probability of infection. JPC15.2 Page 23
Macrofil Chemotherapy hoject
Potential macrofi laricidal compounds
90. Ciba Geigy has informed WHO that it will no longer continue development of Amocarzine (CGP 6140) for onchocerciasis, but is willing to transfer all information relating to this drug to Macrofil to allow its further development with another collaborator. A legal document to cover such transfer has been submitted to Ciba Geigy. Providing that reanalysis of existing tabletted material shows no degradation, the optimal 3day dosing schedule from the Latin-American clinical shrdies of Ciba Geigy will be reevaluated by the Onchocerciasis Chemotherapy Research Centre (OCRC), Ghana, in the near future. If remaining drug supply available within Ciba Geigy proves to be unusable, then the costs and advisability of resynthesis of Amocarzine by another company will be considered. Further development of Amocarzine for onchocerciasis will be dependent upon the results obtained in West African clinical trials, and the costs of independent development.
91. Clinical snrdies on the use of high-dose ivermectin (up to 800 pglkg) in OCRC, Ghana, have indicated that no unexpected adverse effecs occur in treated onchocerciasis patients. Results of these snrdies have been submitted to Merck & Co. for consideration of routine use of higher levels of ivermectin in single or repeat doses. Such high-level dosing schedules may enhance the observed effects of repeated dosing on female wonn fecundity, and could also be used to prevent the emergence of drug resistance.
92. The irreversible anaemia produced by Ciba Geigy compound CGI 18041 during its preclinical animal testing led to a decision not to take this drug into human clinical trials.
93. The benzimidazole compound, UMF 078, has entered the preclinical testing phase, and shown to be well tolerated in acute toxicity tess in rodents. Results of mutagenicity and teratogenicity studies will be critical for its further development.
Potential resistance to ivermectin
94. Two model nematodes resistant to ivermectin, one parasitic and one free living, are being snrdied with the aim of developing "molecular probes" able to identify individual wonDs which are resistant to standard doses of ivermectin. A simple sl2ining technique has been developed, but is applicabiliry to microfilariae of Onchocerca is not yet known.
95. In view of the recommendation from EACI5 that development of new macrofilaricides should terminate in 1997, and that ttre activities of Macrofil to that time should focus on compounds identified as clinical trial candidates, the work plan of Macrofil is being revised to implement the recommendation.
DEVOLIJTION
96. As in previous years, the Unit's plan of activity for the period of January to December 1994 highlights the advisory and catalytic role that it has to continue to play as regards 6xinin8, the raising of the awareness of the authorities and general public, epidemiological surveillance and ivermectin treatment of patients, the preparation and update of the countries' devolution plans, mobilization of resources for the implementation of the plans, and support to operational research. JPCl5.2 Page 24
97. To implement this plan, the Unit has worked, as usual, in close collaboration with the other OCP units, the WHO Regional Office for Africa, particularly through the Intercountry Devolution Coordinator, and the WHO headquarters in Geneva. Besides, the contacts benveen the unit and the Participating Counnies have been continued, notably through missions and meetings organized periodically.
98. The impact of OCP devolution activities can only be measured through the activities really carried out by the Participating Countries themselves and this is what document JPC15.8 tries to reflect. Consequently, ttris progress report on devolution will be confined to the laying of emphasis on some particular poins such as ttre institutional framework for devolution and the roles of the main actors, training, the raising of the awareness of the populations by OCP, the programming and evaluation meetings organized by OCP and the presentation of the criteria defined by ttre devolution unit for the assessment of the capability of the countries to maintain OCP's achievements.
Institutional framework for devolution and the roles of the main actors
99. During its fourteenth session, ttre JPC asked for a revision of document JPC14.7 entitled "lnstitutional framework for devolution and the roles of the main actors". The OCPiNational Coordinators' meeting, held in March 1994, revised this document. Table 5 summarizes the results of the work.
Training
100. To guarantee the success of the devolution process, the Programme has continued is training policy by awarding fellowships for specialization to nationals of the Participating Countries in the following main fields: epidemiology, health services management, public health, health education, ophthalmology, statistics and informatics, medical entomology and environmental sciences.
101. Furthermore, as in the past, in-service and field training is being continued and centred mainly on the methodology and epidemiological evaluation of onchocerciasis, ivermectin disribution and post-treatrnent surveillance, different blackfly snrdy and control techniques and, finally, management. Special emphasis has been laid on the maining of the national coordinators and other national team workers in the OCP methodology for the analysis and interpretation of active epidemiological surveillance data and on the introduction of the workers concerned to the use of computers.
102. As regards the blackfly control methods, the unit is anaching more and more importance to the training of villagers in the ground larviciding technique in order to prepare the communities to control, themselves, if need be, any blackfly nuisance detrimental to their socioeconomic development activities. To that end, 30 persons have been trained in Burkina Faso, 20 in Mali, 10 technicians in COte d'Ivoire and t I in Sierra Leone. The trained technicians will play the role of trainers in this field.
103. Training seminars organized by some Participating Countries also benefited from the active parricipation of the unit, particularly through the devolution animators. JPCl5. Page2J' b (l, U o It) hcD tsR l)O. o rt) o Cl! \J co a) oi oO rnB C)s rrEE9 rrl.L ! -5 6 =Il oj o o .9 oo gE .o & olJ :E .E '= (t, Ei :ar* '5 9=o 6o. * H o E Lr.> tc) o e'5 0)r\ Es 4= o' E€ .'' EE r F.E ar 99 66o I E-8 90 Q9 EE ,.o6r tr to .= H6 .=& EH i Gl= h.{o 500 c!(a JV 'E' cr, -o ).tr €s €E q)e g() ll)E = !c Er AE o.= o Fo .b€ EE o99 > O- eE; '5$r(, (!o9c .gb.)u, 50Ec E E"E E sE c(lt C)xiJtr =-9 s.E 9.E E € Ps gE rr C) o- t'E I .=(gtr EH EEA a)oE E E.O E Eg oH o o.c FO(J rr!.oi r-.o'fi E FE-o.oBE FO. ^>|r .O'E € o ol F€.9 FE(tl F F5 I atr I
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u)l r!l u)l >t r!l FI t-l (JI ctl qtl rIJl JI F.l EI ol OI=l ot &l 104. As shown in Table 6, between August 1993 and July 1994, the Programme awarded 32 fellowships (24 to men and 8 to women) in the following disciplines: - Health services management 8 - Entomology 3 - Epidemiology l1 - Public health 4 - Ophthalmology 4 - Health education I - Environmental sciences I 32 Table 6. Breakdown of fellowships by country and by discipline (August 1993 - June 1994) Health Entomo- Epide- Public Ophthal- Health Enviro- Total Mana- logy miology Health mology Educa- nmental gement tion Sciences Benin 2 I I 3 I 8 Burkina Faso 3 ) 5 C6te d'Ivoire 3 3 Guinea 3 I 4 Guinea-Bissau I I Mali I I 2 Niger 2 I 3 3 Senegal 1 2 Togo I I I 3 Total 8 3 11 4 4 I I 32 105. As at 31 July Lgg4, 430 nationals of the OCP Participating Countries, including 29 women, had benefited from OCP fellowships from the beginning of the Programme (1974) to tttis time (July 1994). The situation of these 430 beneficiaries of OCP fellowships is as follows: - beneficiaries working in the Onchocerciasis Control Programme . . . . about 50% - beneficiaries working in the Ministries of Health of the States about 30% - beneficiaries working in other government and non-govemment bodies about 10% a - beneficiaries still under training about 8% - beneficiaries no more working or lost sight of ....about}% 106. The analysis of the situation reveals also that only about I0% of the fellows have been trained in epidemiology while the success of the devolution process necessarily calls for the strengthening of the epidemiological surveillance capability of the OCP Member States. To r.medy this shortcoming, the Programme, on the one hand, gives priority to fellowship requests for training in epidemioiogy, and, on the other hand, lays special emphasis on collaboration with other partners like WHO/AFRO, OCCGE and the ESSP Project (Epidemiological Surveillance JPC15.2 Page 27 Support Project) whose training activities are aimed at strengthening the epidemiological surveillance capability of the countries at all the levels of the health pyramid, particularly the peripheral level. The ESSP Project, which is at presenr established in Burkina Faso, C6te d'Ivohe, Mali and Niger, is an epidemiological training project financed by the Canadian Inrcrnational Development Agency (CIDA). 107. The purpose of the ESSP Project is to establish and make operational Epidemiological Surveillance Centes (ESCs) in the regions, provinces or districts as a supplement to the existing health information network. The ESCs are capable of collecting and analysing health information, reporting on it to the local and national authorities and creating feedback for the peripheral health centres. Those who work in the ESCs have been trained in epidemiology and data processing and the centres equipped with computer equipment adapted to field conditions. 108. OCP, through its devolution unit, encourages ttris type of training which fully mees one of its principal preoccupations concerning devolution: to train epidemiologists and make them operational, particularly at the district level in the eleven OCP Participating Countries with a special emphasis on the onchocerciasis-freed zones. That is why the joint training project in operational epidemiology and management, which is being prepared for the 1l OCP Participating CounEies and will be submitted to ttre African Development Bank for financing, is based strongly on this ESSP Project which, as mentioned above, is already established in the subregion and continues to demonstrate its efficacy. htblic awareness and population mobilization effort by OCP (see also para. 157 to 168) 109. The unit continues to coordinate in close collaboration with the Vector Control Unit, a vast information campaign conducted every week by subsector and sector chiefs during their routine field visits. The main themes treated during these sessions are still the same, i.e., the return of the blackfly after the cessation of larviciding, the role of ivermectin in ttre prevention of blindness and in the control of onchocerciasis-caused morbidiry, the need for community participation in all activities aimed at preventing recrudescence of onchocerciasis or ssn6slling this recrudescence, if necessary. tl0. As a consequence of this awareness-raising effort, unlike what happened in 1991, practically no complaints have been received from the populations concerning blackfly nuisauce in the zones of the original Programme area where larviciding operations have definitively ceased although blacldly densities have remained the same as those obtained in 1991. I I l. However, the fear of the blackfty which the populations still conrinue to identiff automatically as a cause of blindness has not completely ceased and the sensitization effort undertaken by OCP must be continued together with that made by the states themselves in this field (see document Jrc15.8). Meeting on evaluation and programming of devolution activities in the countries ll2. As in 1993, an OCP/National Coordinaors meeting was held from 2l to 23 March 1994 at the OCP headquarters in Ouagadougou. All the National Coordinators of the eleven Participating Countries were present. This meeting, on evaluation and programming of devolution activities carried out by the countries, examined the progress made since the last meeting in 1993. Furthermore, it was aimed at providing answers to the questions raised by the JPC, during its fourteenth session in December 1993, in Luxembourg, on the devolution process. JPC15.2 Page 28 113. This evaluation has shown that the countries continue to really attach importance to ttre safeguarding and strengthening of OCP's achievements, which is reflected in the devolution activities they have been carrying out in the field in varying degrees without external funding (see document JPC15.8). Besides, efforts are being made by the national health authorities to involve the peripheral health services and rural communities in the different devolution activities, which is an important step towards ttreir integration into the other basic socio-health facilities of the countries. However, as underscored in ttre OCP 1993 progress report, the complete success of this integration implies, necessarily, a restnrcturing and srengthening of the health services. Meeting on the strengthening of epidemiological surveillance for integrated endemic disease control in West Africa building on OCP experience 114. Still wittr a view to the finding of solutions to the crucial problem of integration of the different endemic disease control prograrnmes, a meeting was held from 24 to 26 March 1994 at the OCP headquarters in Ouagadougou. Present at the meeting were: all the OCP National Coordinators of the eleven countries concerned, all national officials responsible for major endemic diseases or departments of preventive medicine in the OCP Participating Countries, representatives of WHO (Headquarters and the AFRO Regional Office), the chairman of the OCP Expert Advisory Comminee, experts from different backgrounds and OCP representatives. 115. The objective of the meeting was: - to identify the problems and constraints related to the integration of endemic disease control programmes in the context of the multidisease surveillance and control approach; - to find solutions to such problems and overcome the constraints; - to study how the OCP managerial and operational experience and facilities could support multidisease surveillance and control programmes. 116. Before tackling these subjects, the meeting considered it essential to identify beforehand the elemens common to the different country programmes by limiting itself to the following four fields of action: health education, epidemiological surveillance, prevention and patient care, monitoring and evaluation. lL7. The four working groups set up to deal with these subjects showed seriousness in their tasks but did not have enough time to complete the subjects because of the number of endemic diseases concerned and the complexity of the topics tackled. Another meeting is planned in order to finish ttre group deliberations whose results will make it possible to better rationalize the use of the available resources through integration prograrnmes designed on a more realistic basis. 118. Discussions then took place on the problems and constrains related to ttre integration of endemic disease control prograrnmes and on possible solutions to these problems. The following were the essential poins which emerged from the discussions: - the need for the states which have not done so yet, to prepare a clear integration policy which defines the role of the different actors; - ttre integration must not lead to a complete disruption of what exists already. The existing facilities must absolutely be taken into account. JPCl5.2 page 29 - the integration does not necessarily mean a total negation of all existing vertical Programmes; - the need for a real decentralization of health care and implementation of the different programmes; - the problem of staff, in terms of number and qualiry, and of their motivation are posed in many cases and decision-makers must pay attention to them; - the attinrde of the donor partners is a deciding factor in the success of the implementation of the different programmes in an integrated framework. 119. As regards the use of OCP's facilities and procedures in support of multidisease surveillance and control programmes at the regional level, the .ss1ing, first of all, recognized the invaluable role played by the OCP facilities esrablished in the Participating Countries in the success of onchocerciasis control and considered that these facilities should, in due course, be transferred to ttre countries concerned. It then recommended: - that OCP should ake all the necessary steps for these facilities to be really available in a satisfactory state; - that the countries and OCP should consult each other in order to identify the possibilities for the use and maintenance of these facilities for the strengthening of the national health services. 120. Finally, in view of the statutory responsibility of WHO in the health development of the countries, the meeting recommended that, at the country, regional and global levels, WHO should sfrengthen its collaboration with the countries in their efforts to implement OCP devolution activities and in the improvement of multidisease surveillance and control. Criteria for the assessment of the capability of the Participating Countries to crrry out effectively onchocerciasis recrudescence detection and control l2l. The essential task of the OCP Devolution Unit, which was set up in August l99l following the recommendations made in 1990 by ttre OCP External Review group, is o coordinate all activities which should allow OCP to anain the last part of its objective which is "to ensure that the Participating Countries are in a position to maintain the programme,s achievements". To be in a position to maintain the Progranrme's achievemes6 111sans, i1 concrete terms for the counnies, being able to detect any recrudescence of onchocerciasis in time and controlling it with an appropriate chemotherapy (ivermectin treatment). 122. It has therefore become essential to define criteria which would make it possible o assess the capability of a Participating Country to undertake effectively this activity of detection and control of onchocerciasis recrudescence. The devolution unit has tackled this ask and selected a number of criteria which could now serve as indicators for the evaluation of this capability of the countries to maintain the Prograurme's achievements. These criteria are as follows: (a) Human resources - Existence of national senior officers and technicians trained in fields related to the JPCI5.2 Page 30 devolution of OCP (epidemiology, public health, healttt services management, entomology, ophthalmology, erc.); - Existence of active epidemiological surveillance and onchocerciasis treatment mobile teams available at the central and regional or district levels; - Existence of fixed health centre medical staff retrained to undertake passive surveillance of onchocerciasis and treatment of onchocerciasis-patients with ivermectin. (b) Existence of an active national structure for the coordination of devolution activities (devolution committee). (c) Existence of a national programme aimed at integrating onchocerciasis-related activities with those of other endemic diseases (national devolution plan). (d) Having carried out the onchocerciasis surveillance activities independently and many times before the end of OCP by integrating them with the surveillance activities concerning other endemic diseases ("running-in" of the system by the implementation of the whole or part of the national devolution plan). (e) Gradual financing of the greater part of the onchocerciasis surveillance activities from the country's own resources in order to ensure the sustainability of the activities. (f) Rural communities prepared for an active participation in the activities. (g) Existence of an operational epidemiological surveillance network at the national level. Conclusion: How can the chances of success of the devolution process be increased? 123. Once one has ttre assurance that the countries are in a position to detect early and control any onchocerciasis recrudescence, to increase the chances of success of the devolution process, it would be desirable that a number of conditions be met and that some key actions be taken primarily concerning the Participating Countries themselves but also OCP and the whole international community, viz: Participatine Counnies - To continue to show a flrm will not to see this scourge of onchocerciasis reappear again. - To establish a mechanism for ttre intercountry coordination of their devolution activities. - To release resources for the implementation of these activities. - To integrate the activities, to the extent possible, wittt those of the basic health facilities in order to ensure their sustainability' tPcts.2 Page 31 - To let the rural communities ttremselves participate actively still with a view to the sustainability of the activities underaken. - To promote, with a view to the safeguarding of environmental resources, socio- economic development in the onchocerciasis-freed areas in order to give the populations the means and motivation for an active participation in activities aimed at the promotion of health in general and OCP devolution in particular. OCP - To reduce the disease to the lowest possible level so as to prevent or delay significantly the emergence of recrudescence. - To involve as many partners as possible, at all levels, through a sustained awareness- raising campaign in order to ensure that onchocerciasis would no longer become a public health problem. - To make available and within everyone's reach the necessary devolution tools (ivermectin, macrofilaricides, diagnostic methods, different systems of distribution of the drug and of treatrnent of patiens, etc.). WHO and international communitv - To continue with the technical and financial support to OCP up to some time around the year 2000. - To support the implementation of the devolution plans of the countries. - To help in the strengttrening of the health facilities of the countries. - To support the establishment of a mechanism for the intercountry coordination of devolution activities. - To help the countries to carry out socioeconomic development in the onchocerciasis- freed areas. N)MIMSTRATION AI\D SI.]PPORT SERVICES Objectives, organization and functioning of services 124. The Administration and Support Services Unit supports the other OCP operational, technical and scientific units in the whole Prograrrme area while seeing to it that the Programme's human, financial, material and information resources are used optimally. This calls for continuous sensitization of the Administration on the evolution of the Programme's activities, needs and resources available. 125. To carry out its task, the unit has to manage the budget and finances, personnel, logistics, infrastnrcrure and services. Furthermore, it has to contribute to the overall management and most rational possible functioning of the organization. To achieve this, the unit contributes to the extension of the field of computer applications and has stengthened the managerial capabilities of the staff, notably through management seminars. JPC15.2 Page 32 Administrative costs 126. The trend of the administrative costs since 1990 is a correct reflection of the efforts which are made to maintain the operating costs at the lowest possible level. The slight rise in 1993 was due to the ever-increasing cost of staff salaries. Since the annual expendinrres of the Prograrrme as regards the operations are on the decrease, it is certain that, in the short term, the operating costs will tend to represent a greater proportion of the total expenditures. A proportional decrease in the administrative costs will be made over time. Table 7: Coss of the Administration and Percentage (US $) UNIT 1990 I 99 I t992 1993 1. Office of the Director 847,919 948,949 743,449 585,650 2. Administration and Support services 2.532.698 2,405,602 2,622,244 2,679,531 3. Support services in Geneva 322,395 359,308 398,577 408,451 Total 3,703,012 3,713,859 3,764,270 3,673,632 Total expenditure 30,432,360 32,543,360 31,716,197 26,503,663 % of administrative costs 12.2% tL.4% rL.9% L3.86Vo Budget and Finance 127 . More than 40% of the 1993 Budget was implemented in CFA franc, the local currency predominant in the Programme area. Since all expenditures are posted in dollars, the trend of tre rate of exchange of the dollar in relation to the CFA franc continues to have a considerable impact on the implementation of this budget. The first three budges of the fourth financial phase (lgg2-lgg7) were prepared at a similar exchange rate of CFA 285 to the dollar and implemented in 1993 at a slightly unfavourable rate of CFA 282, and therefore having only a slight effect on the firnncial results. 128. On the other hand, the year 1994 started with the announcement of a 50Vo devaluation of the CFA franc; for the period of January to June 1994, the average rate was CFA 577 to the dollar. At this rare, the 1994 budget will be implemented with considerable savings even taking into account the feared increases or those which have already taken place, notably concerning salaries and utilities like fuel. The effect of this variation in the dollar exchauge rate has been controlled by ttre computerized financial system which allows the readjustment and continuous update of ttri different obligations established. This situation has made it possible to get a credit balance of US$ 3,235,337 on the second budget of the fourth Financial Phase. Personnel l2g. The constant objective of the Administration unit is to make available to the whole Frogramme sufficient qualified staff, within the limits of the budgetary authorizations. Field missions of officials of the Administration are, therefore, always opportunities to inform and retrain management staff with a view to improving output so as to achieve sound, effective and transParent management. JPC15.2 Page 33 130. The number of staff, which represents the greatest budget line of the annual budget, i.e., slightly more than30Vo of the expenditure, has been decreased considerably in 1994 *O it now around 780 posts (Fig. 13). Nottring has been spared with a view to reducing staff: non- automatic renewal of professional posts which become vacant, non-renewal of contracts for poss considered less essential, revision and regrouping of duties, sharing of support services between unit chiefs, use of services of temporary rather than permanent staff. 131. During the past 12 months, five professional posts have been abolished, reducing the number of staff of this category to 26, i.e., 13% of the staff under WHO status. In addition, the Programme employs 14 persons under the short-term professional saus, i.e.,77o of the staff. At the s:rme time, nine general service posts were abolished as a result of the change of the incumbents from WHO status to national status. Seventeen other posts in the sirme category have been abolished as part of the staff reduction, bringing ttre total number of general service posts abolished to 26. Taking all the reductions into account, the number of general service staff amounts to 160, i.e.,80% of the total stalf under WHO status. To these figures must be added that of the staff of the national teams (including all categories) in the OCP western extension which is 320, bringing the overall Programme staffto 780 as at 31 August 1994 (Fig.13). 132. In all, three poss, all in the professional category were advertized for external recruitrnent during the period covered by this report and concern: - one medical officer/epidemiologist - one Information Officer - one Personnel Officer (recruitment in progress) All these posts beqlme vacant as a result of contract terminations, departures on retirement or reassignments. 133. One female application was received for the post of Information Officer but the candidate did not possess the requisite qualifications. The Programme continues to pay particular attention to the examination of female applications because of their low representation in OCP. Supply and Services L34. A rigorous management of the stocks and stores, in all its forms, has enabled substantial savings to be made on the purchase of supplies and parts necessary for the operations. Dynamic inventories have been made with the help of the computer and have resulted in the identification and the offering for sale of old equipment or the priority use of surplus items before making new orders. 135. The expenditure on the purchase of equipment, items and other goods needed by the Programme has been of the same order as that of the other years of this fourth financial phase. It was US $5.1 million: larvicides accounted for US $3.1 million of the budget, petroleum producs for US $665,000, spare parts and vehicles for US $873,000, water, etectricity and telecommunications for US $270,000 and the expenditure on miscellaneous equipment was US $170,000. Out of these amounts, 75% was processed by the central purchasing division of WHO/Geneva, often through tenders, and 25% for local purchases. The expendinre on constnrctions and renovations has been limited to US $7,000, and this concerns the support premises for the Bouake and Bamako installations. tPcrs.2 Page 34 Transport and communications 136. At the end of the period under consideration, the Programme was using 319 vehicles; it has not yet been possible to reduce the vehicle fleet to about 300 as was planned to be done after the closures or reorganizations of subsectors and operational bases. Rather, it has been decided to extend the life-span of the existing fleet by limiting as much as possible the number of new vehicles: only nine new vehicles have been received during each of the past two years. The light liaison vehicles as well as the heavy transport vehicles are no long replaced, only cross- country vehicles are now replaced on a very selective basis. 137. From I September 1993 to 3l August 1994, the vehicles covered a total of 6,170,356 km and consumed 1,020,063 litres of fuel. The vehicle fleet has remained 95.L3Vo operational in the Programme area. 138. Out of the whole fleet, 98 vehicles have been loaned to the western extension countries for the duty travels of the national teams. Regular maintenance of these vehicles is made by the national teams while OCP supplies the fuel, lubricants and spare parts and is responsible for the technical supervision. To strengttren the devolution progralnme, seven other vehicles have been released to the Participating Countries. 139. Forry radio-communication stations are in operation, six of which have teletypes. 140. The computerization of the spare parts central store has been completed. Steps are being taken for the management of all the stores and vehicle spare parts from Ouagadougou. This makes possible now the rapid identification of old spare parts and their sale. Programmed invenrories allow the identification of parts which are not requested much (dormant stock) or ttrose which would be damaged or unusable. PI,'BLIC RELATIONS, INFORMATION AND DOCI,]MENTATION ACTTVITIES lVith the World Health Organization l4l. The Programme Director anended various stailtory meetings: - Regional Comminee (43rd session), from 1 to 10 September 1993 in Gaborone (Botswana); - Executive Board (91st session), from L7 to26 January 1994 in Geneva; - World Health Assembly (47th session), from 2 to 12 May 1994 in Geneva 142. During these meetings, the Programme Director had discussions with the WHO Director General. In Geneva, he also met other officials in the WHO headquarters. 143. The WHO Representatives in Bissau, Conakry, Freetown, Abidjan and Bamako were visited in October 1993, March 1994, April 1994 and May 1994 by the Programme Director. lM. On 6 May 1994, the World Health Assembly corlmemorated, during a solemn ceremony, ttre 20th anniversary of the Onchocerciasis Control Programme in the presence, notably, of the Ministers of Health of the eleven Participating Countries, the WHO Director General, representatives of donor countries and organizations and the Committee of Sponsoring Agencies. IPCL',2 Page 35 145. In a press release issued on the occasion of the 20th anniversary of OCP, the WHO newsletter "WHO-Press" (WHA/8, dated 6 May 1994> stated, notably, that OCP nis unquestionably one of the greatest success stories of the World Health Organization since the eradication of smallpox". e With the Participating Countries L46. The Programme Director was received in audience by: - the President of Burkina Faso, His Excellency Mr Blaise Compaore, on I April 1994; - the President of Mali, His Excellency Mr Alpha Oumar Konare, on 9 June 1994; - the Ministers of Health of Senegal, Guinea-Bissau, Guinea, Sierra I-eone, Congo, Cdte d'Ivoire, Mali and Burkina Faso in October 1993, and in March, April and May L994. It should be noted that during the 47th session of the World Health Assembly in Geneva, he had discussions with all the Ministers of Health of the OCP Participating Countries ; - the Minister of State, Minislgl of Foreign Affairs of Senegal, in October 1993; - the Minister of Agriculture of C6te d'Ivoire, on 4 March 1994, in Abrdao. I47 . The hydrobiologists of the Participating Countries held their annual meeting from 27 to 31 January L994 in Bamako (MalD in the presence of officials of the OCP Vector Control Unit, experts from ORSTOM and the chairman of the Ecological Group. A day was devoted to a joint meeting with the members of the Ecological Group. 148. From 2l to 23 March and,24 to 26 March 1994 respectively were held in the OCP headquarters in Ouagadougou the meeting of the National Coordinators of the 1l Parricipating Countries and a meeting on the strengthening of epidemiological surveillance for integrated control of endemic diseases in West Africa building on the OCP experience (see the chapter on Devolution). With the statutory bodies L49. The Ecological Group held its fifteenth session from 31 January to 4 February 1994 in Bamako (Mali) while the Expert Advisory Committee (EAC) held its fifteenth session from 6 to l0 June 1994 in Ouagadougou. The EAC repoft will be presented to the current session of the JPC. 150. The Committee of Sponsoring Agencies (CSA) met on 23 and 24 September 1993 (58ttt session) in New York, 6 and l0 December 1993 (59th session) in Ilxembourg, 15 April 1994 (60th session) in Paris, and 7 and 8 July 1994 (61st session) in [,ondon. 151. From 12 to 14 April 1994, the OCP Committee of Sponsoring Agencies organized, in Paris, a ministerial meeting on sustainable settlement and development of the OCP area. The opening ceremony was presided over by Presidens Abdou Diouf of Senegal and Blaise Compaore of Burkina Faso and the representative of President Jerry Rawlings of Ghana. JPCI5.2 Page 36 152. On 4 November 1993, Mr Attila Karaosmanoglu, Executive Director of the World Bank, visited the OCP headquarters in Ouagadougou. He was received by the OCP Director in the presence of the staff members. After listening to the different unit chiefs who briefed him on OCP's operations, the results obtained and the future prospects, Mr Attila Karaosmanoglu said he was pleased to meet officials and staff of the Programme and expressed his satisfaction at the quality of the work being done in it, the availability and competence of is leaders and the excellent management. With the donors 153. The Programme Director visited Paris (France) from 11 to 15 December 1993: Washington (USA) from 2l to 25 January 1994 and 19 to 22 June 1994; London (U.K.) from 19 to 20 April 1994, then 12 to 16 May 1994 and 16 to 19 June 1994; Geneva (Switzerland) from 20 to 24 April 1994; Frankfurt (Germany) from 3 to 4 May 1994; Amsterdam (Netherlands) from 19 to22 June 1994; and Copenhagen (Denmark) from 22to25 June 1994 for discussions with the OCP donors. With the aerial spraying contractor 154. The working relations between OCP and Evergreen Helicopters, the company responsible for the aerial larviciding, continue to be good. The Expert Advisory Committee made a recommendation during is fifteenth session (Ouagadougou, 6 - 10 June 1994) in which it expressed is preoccupation that a change in aerial conEactor, for the 199611997 period, could jeopardize the smooth running of vector control. Meetings are held regularly, in the field, as well as in the OCP headquarters, between officials of Evergreen and OCP to discuss problems and difficulties encountered and find solutions satisfactory to both parties. With the scientific community 155. The Programme participated in the following meetings: - From 27 to 29 September 1993, the Chief of the Biostatistics and Information Systems Unit (BIS) participated in a meeting in Geneva on the effects of repeated ivermbctin treatrnent on onchocercal ocular lesions. - From 25 to 29 October 1993, the OCP Director and the Chief of the OCP Devolution Unit participated in a meeting at the headquarters of the WHO Regional Office for Africa in Brazzaville to inform WHO/AFRO of devolution activities. I - On 13 December 1993 in Basle (Swiuerland), the Chief of the OCP Epidemiological Evaluation Unit (EPI) participated in a meeting with Professor Weiss on the development of an immunodiagnostic test for onchocercal infection. From 15 to 21 January 1994, the OCP EPI Chief participated in Ibadan (Nigeria) in a workshop on the development of a protocol for monitoring ivermectin distibution. From 9 to 14 February 1994, the Chief of the OCP Devolution Unit took part, in Paris, in a conference on trypanosomiasis organized by ORSTOM. From 16 to 19 April 1994, the OCP Director participated in the meeting of the Board of Directors of the Hunger Project in Dhaka (Bangladesh). JPCt5.2 Page 37 - From 24 to 29 April 1994, the OCP Director attended a conference on telecommunications and health in Cairo (Egypt). - From 15 to 19 May 1994, ttre Programme Director took part in the meeting of the Mectizan Committee in Clermont-Ferrand (France). - From l0 to 19 June 1994, the OCP EPI Chief participated in a workshop in Bamako (Mali) on the development of an inter-sate protocol for the study of ivermectin self- treatrnent for onchocerciasis control. - On 26 June 1994, the Programme Director attended a JCB/TDR meeting in Geneva. 156. The Programme was visited by: - an important delegation of 60 persons from the Centre for Higber Sudies on Modern Africa and Asia (CHEAM) led by Mr Douglas Gressieux, on23 March 1994, in the absence of Mr Philippe Decraene, CHEAM Director (13 rue du Four, 75006, Paris) who could not come. - 20 West African trainees from the Pan-African Institute for Development (IPD/AOS) in Ouagadougou, accompanied by their trainers. - Mr Desire Berckmans, Belgian Journalist-Film-maker, on27 May 1994. - Mrlssouf Zabsonre, Burkinabe journalist wittr the newspaper 'Sidwaya', on 8 February 1994. With the general public 157. The periodical "Oncho Information' has maintained is copies at 5000 in French and 3000 in English. For the flrst time, in June L994, it interviewed the chairman of the Expert Advisory Committee (EAC) after the l5th EAC session and on the occasion of the 20th anniversary of OCP. "Oncho Information" has tried to adapt itself to the trend of the Programme and to the devolution process. 158. The Prograrnme Director gave interviews to many African, European and North American radio and television stations. 159. In its issue of 25 January 1994, the Burkina Faso daily, "Sidwaya", took advanage of the inauguration of the important Bagre dam (water supply, electricity and agriculnrral complex) presented as the most ambitious of the socioeconomic projecs in Burkina Faso, to recall that witttout the victory won over onchocerciasis in Burkina and in the Bagre area (Boulgou province) by OCP, the Bagre project would have been jeopardized. 160. The magazine "Jeune Afrique-Economie" published in February 1994 under the tifle nWhen a health prograrnme comes to ttre aid of the economy", a very good article on OCP. This text comprises a column entitled 'Ebrahim Samba's secret" in which ttre OCP Director declared, notably: "The secret of our success is stringent [umagement" followed by this co[rment by the international monthly 'An attinrde approved by the international donors". 16l. On 7 and 8 April 1994, the Programme Director attended the funeral of the late President Felix Houphouet Boigny of Cdte d'lvoire in Abidjan and Yamoussoukro. JPC15.2 Page 38 162. On the occasion of OCP's 20th anniversary, Mr Bernard Surugue, producer of the OCP reference film , "Mara, the Lion's Look" (1976), and collaborator with WHO/Headquarters in Geneva, visited Mali from 13 to 18 March 1994 to make a sequence of a few minutes, a sort of complement to the film "Mara, the Lion's Look, essentially devoted to ivermectin distribution, community ivermectin treatrnent and some devolution activities. 163. The OCP documentalist led an OCP team to l-eo (Sissili province), Burkina Faso, to organize "Oncho Games" from 23 to 30 March 1994, in collaboration with the General Inspectorate of Basic Education. This event sponsored by the World Bank, which was a great success, was organized on the occasion of the holding in Paris, from 12 to 14 April 1994, of the Ministerial Meeting on sustainable settlement and development in the OCP area. 164. On24 March 1994, the OCP Seguela subsector (Cdte d'Ivoire) received a C6te d'Ivoire television crew that came to produce a prograrnme on "Water, the environment and water-borne diseases". 165. The international weekly magazine, "West Africa", published in its issue of 16-22May 1994, under the column "Profile", an article entiiled "Dr Ebrahim Samba, head of WHO's River Blindness Programme - A leading figure". 166. On 6 June, the Guinea television station, in collaboration with the Guinea national oncho team showed the sequence on onchocerciasis and OCP (15 minutes) of the 60-minute documentary "Friends in Need", ordered by the Kuwaiti Fund for Arab Economic Development and produced by McKinnon Films Limited (U.K.). Since the commentary on the film is in English, the Guinea TV station has made a translation and dubbing of the original text. It is a praiseworthy initiative. 167. "Jeune Afrique-Economie" also published (issue No.180 - June L994), a quality article on the Ministerial meeting in Paris (12-14 April 1994) on the sustainable settlement and development in the OCP area. Many newspapers, generally weeklies and some dailies ('Sidwaya" and "Observateur" in Burkina Faso), ('I-e Soleil" in Senegal) whose special correspondents accompanied Presidents Blaise Compaore and Abdou Diouf to the French capital, informed their readers of the conclusions of the ministerial meeting, laying emphasis on the need, for the countries concerned to coordinate their development policy. 168. The sequence entifled "success in Sight", dealing with onchocerciasis and OCP, shot in Burkina Faso and Mali in 1993 by the UNDP Television Programme crew, "Azimuts" (based in the Palais des Nations, Geneva), was shown in all ttre OCP Participating Countries. 'Azimuts" is distributed in 126 countries and is intended to be a third-world positive approach. hrblic relations and documentation 169. The Programme continues to make known its activities by puning at the disposal of the public, NGOs, the media, universities, the scientific community, collaborators and friends of OCP, video copies, photographs, slides, erc. The update of the OCP photograph bank is in progress. Tho OCP Information Offlrcer takes advantage of his field visits to improve the selection of OCP photographs. 170. During the period covered by this report, ttre OCP Documentation Centre was visited by 870 persons. [t made available to is users 316 books, sent 280 off-prins in Africa and the rist of the world, disnibuted 5300 brochures entitled "Success in Sigbt" and "Insecticide JPC15.2 Page 39 Research" and 4500 oncho badges; 150 video copies of OCP films were made available to the public, universities, health centres, youth centres, culnrral centres, OCP sectors and subsectors, national oncho teams in ttre Participating Countries, etc. L7l. The Centre ordered and receivedSz} books, renewed the subscriptions of 23 titles and periodicals and regularly received free of charge 44 other periodicals. 172. With a view to a bener knowledge of the Centre, a brochure has been prepared by the OCP documentalist and 5000 copies printed. 173. From 19 to 30 April 1994, the OCP documentalist attended the fourth congress of the Association for Health Information and Libraries in Africa (AHILA), in Karpala (Uganda). At the end of the congress, she was elected Vice-President of AHILA. 174. Since November 1993, at the initiative of ttre OCP documentalist, and in collaboration with some ten documentation centres in Burkina Faso, a biomedical information network has been established. 175. hrblished by the World Health organizxfio1, the English version of the book by E.M. Samba (OCP Director) entitled "Onchocerciasis Control Programme: A lesson in public health' came out in May 1994. 116. On the occasion of the 20th anniversary of OCP, a new brochure "OCP: 1974 - 1994" published in the Programme's two working languages, was made available to the public. Internal meetings 177. The Programme organized several internal meetings, the most important of which were: - Meeting of the eastern and western operational zones, from 2 to 6 November 1993 in Kara (Togo) and 16 to 20 November 1993 in Bamako (Mali) respectively. - Meeting on operational research and strategies, in Ouagadougou (Burkina Faso), on 17 and 18 March 1994. - Meeting on applied research and environmental monitoring (AREM), from 2 to 6 May 1994 in Bouake (Cdte d'Ivoire). - Insecticide meeting, from 9 to 13 May 1994, in Bouake (C6te d'Ivoire). Collaboration with non-governmental organizations (NGOs) 178. As in 1993, OCP invited the representative of an NGO, the same person as last year, to attend the l5ttr session of the Expert Advisory Comminee (EAC) held from 6 to 10 June 1994 in Otragadougou. 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