Proposal for a long-term strategy

onch.ccrciasis control Programme in the votta River Basin area Progr:rmnrc dc Luttc contrc I'onchocercosc dans la Rigion <Ju Bassin <Je la Volta JOtN'l' PROCRANIME CorvlMlTl'EE Officc of thc Clruirrrr.ut JOIITT PROGR.IIIITE COI{IIITTEE Fifth Session Nia^ney, 3-6 Decenber 1984 JPC.CCP COMITE CONJOINT DU PROCRAMMEBureau du P16sidcnt JPC5.7(ocP/84.4) ORIGINAL : ENGLISH The Director of the Prograrune has the honour to submit herewith his proposel for e Lont-Term Strategy in response to the request made by the Joint Progranune Corunittee at its third session in December 1982. During the preparation of this proposal consultetions uere held with all the groups directly concerned uith the Progranme and a number of constructive corutents and pertinent suggestions for improvement of the various drafts were nade. The Director gratefully acknorledges the contributions thus received, uhich heve been taken into eccount in the present docuarent, and feels confident that consideration of the proposed Lont-Term Strateg,y by the Joint Protrsrrne Conunittee will result in the adoption of e Strategy which will guide the future course of the Onchocerciesis Control Programe to the satisf action of all Parties concerned. Provisional asenda iten 9 ocP/EA.4 ONCHOCERCIASIS CONTROL PROGR,AI{I{E II{ THE VOLTA RIVER BASIN AREA PROPOSAL FOR A LOilG_TERI{ STR,ATEGY OCP/LTS 16 .07 . E4 -l TABLE OF CONTENTS SUI{I{ARY 1.1 - 1.9 B. IITITRODUCTION BackFround Purpose and use of the SlSeteg_y Conceptual considerations Terms of reference and backrround doSf4nedelil4 c PROCEDURES FOLLOT{ED IN PREPARING LONG_TER}i STRATEGY OPTIONS Sununarv of procedures Definition of operetional phases Delimitetion of Operational Zones (OOZs) Deterninetion of options Forecasts of the wev in which operetions wiIl develop Cost estimetion Selection of the best option for the Stratecv Issues of criticel importence for selectinR andputtinx into effect an OCP Lons-Terrn Strategv D. PROPOSAL FOR AIiJ OCP LOI{G_TERI{ STR.A,TEGY 14. Possible options and selection of Stretecy proposal 15. The OCP LonE-Terrn Strategv proposal: projected operat ional development 16. The OCP Lont-Tern Stretesv proposal : implications of the projected development of operations 17. The OCP Long-Terrn Straterv oroposal : operations 18. The OCP Lonc-Term Stretecv proposel : expected results and repercussions 19. The OCP ng-Terrn Stratexv pgoposel : shift in the use of resources Pa:e A 2 3 4 5 1 ? 2 3 4 5 5 5 7 9 9 9 11 5 6. 7. 8. 9. 10. 11. 12. 13. The OCP LonR-Tertn S tretecy proposel devolut i on resettlement endThe OCP Long-Term StreteBy proposal soc io-economic development The OCP Lon:-Term Stratery proposal : availebility of a dru6 suitable for large-scele selective populatlon chemotherapy 23. The QCP LonB-Term StrateRv propos a1 evailability of a reliable and convenient diagnostic test24. The OcP ng-Term Stratecv proposal : research and operational studies The OCP Lont-Term S tretegy proposal 22. 20 2L 25. 26. 27. 11 11 11 14 19 19 2L 22 23 25 26 27 2E 28 29 30 The OCP nr-Terro Stratecv propos aI : training : cost estimates Translat i on of the Stretecv into "oln of ection" Anner 1: Annex 2: Annex 3: Anner 4: Annex 5: Anner 6: 11 Terns of Reference Agencies ) . (prepared by the Committee of Sponsoring Delimitation of OCP Operetional Zones Control or No Control of Forest Species of Blackflies Selection of the Long-Term Strategy Proposal from among the Five Opt ions Onchocerciasis Control in the lJestern Extension Area : A brief Description of the Approech OCP Operetionel Zones and corresponding Operational Phases I ocP/84.4 A. SI,.TOTARY 1.1 The overriding consideration in developing and presenting theproposeJ.. for a Lont-Term Strategy (LTS) has been the need for the progranme toreach its overall objective, viz. the elinrination of onchocerciesis as edisease of public-heelth end socioeconomic importance within the ocp area endthe assurence that there wirl be no recrudescence thereafter. L'2 After careful consideration of several possible scenerios, eech basedon a different set of technical and operational assumptions, it yas concludedthet the only strategy that sould al1os the Prograrune to reach its objectivesithin an acceptable period of time and et a reesonable cost was one thatwould effectively preclude the risk of infective bleckflies reinvadiog thepreeent (1984) Protreflme area from outside. The proposal contained in thisdocument therefore calls for full control op.."Cion. in the Southern andlJestern Extension arees. An equelly inrportant consideretion has been the needto protect the populations in these two erees against onchocerciasis andthereby renove a berrier to socioeconomic development. 1'3 ft is also proposed that control of the forest species of blackfly betenporarily discontinued within the present oCP aree and thet operations inthe Ertension areas be aimed at controlling the sevanna species on1y. Thisaspect of the Strategy will be reviewed later if it should be found that t.heforest species are significant as vectors. 1'4 The proposed LTs is based on thorough analyses end evaluations of theoperetional, menagement and scientific erperience of Ocp which have thrornlight oD, and made it possible to quantify, the elements essential forpreparing realistic forecasts sithin the contert of the streteBy. At the saroetirne it must be stressed that given the nature of the onchocerciasis controlProgranune, aDY strategy approved must be flexible and adeptable in i tsinplementetion, so as to avoid it becoming a straightjacket haaperingoperetional freedonr. Also there are severel possible future developaents thatcould heve importent repercussions on ocP activities and the Strateg,y musttherefore be flexible enough to acconuaodate then. For instance, i f eninurunodiagnostic test becarue available or a new drug were developed that wassuitable for large-sca1e selective population chemotherapy, the progrrme, soperational methods sould be considerably affected. 1.5 rnplementetion of the proposed LonB-Tenn strate8y will bring theentire Progranune erea, incl-uding the Southein and Llestern Ertension areas,into the meintenance phasel by r993, i.e. within the twenty-year periodinitially allotted to the onchocerciasis control progranme, and this in spiteof the addition of control operations in the southern part of the rvory coastand in the Southern and the tJestern Ertens ion ereas rhich means treatingalnost t'hree times the length of rivers ever treated in the original ocperee' Furtherrnore, by 1993, the whole of the original protramne area riIlhave been in the maintenance phase for five yeers or more. 1 fn the maintenance phase, nhich follows the at,tack phase ( regula= anduninterrupted vector control operations for 3 years ) and the consolicationphase (in which the frequency and extent of vector control operatioos eredetermined by the findings of the surveillance systern and which lasts for2 years), vector control operations are confined to foci of blackfly reinfestation and the entomological surveillance network is gradually -ahasedout. The maintenance phase lasts ten years. ocP / 84 .4 2 1.6 Another inrportant aspect of the Stretety is its emphasis on an orderly and ""sponrib1" transfer of OCP activities to the Participating Countries. Although it was the Independent Conmission's view that the devolution process would not be launched before early in the nineties, at least as far as vector control wes concerned, subsequent developments have meant that the process can begin earlier and the Long-Term Strate6y therefore suggests that devolution nright start in some of the OCP Operational Zones in the comparatively neer future. 1.7 The operationel costs of the Prograrute resulting from the irnplementation of the proposed Strategy would be US$ 113 'O million and Usg 43.6 million for the third (1986-1991) and fourth finencial phases(1992-1997) respectively, as conpared with Us$ 94.5 million estimated as the ProBra1r1ue cost for the second phase ( 1980-1985 ) 1. The increase in expenditure during the third financial phase as compared with the second phase, viz USE 18.5 mi11ion, would eIlow for fu11 control oPerations in the Southern and ttestern Extension areas which, in turn, will elirninate the risk of trensrniss ion and protect an edditional five million people2 in those ereas. The estimeted cost of the fourth finenciel phase would be less than helf thet of the second phase, and frorn 199E onwards there would be no OCP costs at all, as the ProBrglmle would cease oPeretions in ebout that year. 1.E It has been estimeted that OCP erpenditure on conteininB the effects of re i nvas i on i n the present ( 1984 ) Protrame area ere of the order of US$ 1.1 million per year. Similarly, the costs of controlling forest vector species have been calculated to be of the order of US$ 1.5 million Per annum. These amounts will thus becone available, under the proposed Stratety' for financing operetions in the Extension areas which after a set period wiIl eneble the protremne to be brought to an end: this would othersise not be possible. 1.9 The OCp Strategy is intended to provide a long-terrn PersPective of the lines along which the Progranmre will develop and a general framework for future operations, indicating the activities required and how much they will cost, but not going into operational detail. In other words the Strategy is a general statement of intent; its component parts will be the subject of more detailed pro6ranmring under which separate plans of action will be drawn uP so as to translate the Strategy into operational terms. B IIITRODUCTION Backcround2 Z.l At its third session (December 1982) the Joint Programme Conunittee(JPC) decided inter alia that e LonB-Teg.In Strateg,y (LTS) for the onchocerc i as i s Control Progranure (OCP) should be worked out before the completion of its second financial phase (1980-85) and that this Strategy should be accompanied by a long-term financial forecast for OCP 8s a whole, taking into account devolution in protected areas and ertensions into neH areas .3 1 Th"r" amounts relate exclusively to control operations and therefore do not include allocations for research and training. For more details, please refer to paragraph 26. 2 Tentative figure. 3 Do"u."nt JPCl3, pereBraph 12 .1 ( see also paragraph 11.17 of the ssme document). Ii 3 ocPl84.4 2.2 Since the plannlng and leunching of the Progremne, various bodiesdirectly concerned with it heve offered advisory opinions regerding its future operations shich to varying degrees could be considered as determining strategy. Thus the report of the Preparetory Assistance llission to the Governments of the Participating Countries (PAG) laid dorn the basic strategyfor the Progranme's future operations in the sense thet it specified the control methods to be used end their application, the phases in which the Progranme would be implenented end the resources thet would be required. The PAG forecasts and estimates covered a period of 20 years (1974-1993) and elthough operational experience and scientific investigations heve led todiscoveries which in a few instances have altered the basis for theforecests, the original PAG strategy provided e remarkably good framework forthe gradual development of the Prograrme. ft is thus fair to say that the Progratmte strategy as originally conceived has so far remeined basically unchanged. 2.3 Although the HtlO Evaluation Report on OCP Activities and Accomplishments durin6 the Years 1974 to 1979 wes essentially en essessnrent ofpast performance, the lest section of that report deelt briefly with Prograrme operations as planned for the 1980-1985 period, suggesting that the strategy should remain essentially unchanged. 2.4 Another and more recent exanrple of providing the Progranune aud its statutory bodies with operational forecasts on a longer-term basis wes the submission in August 1981 of the final report of the UIIO IndependentConmission on the Lont-Tenn Prospects of the Onchocerciasis ControlProgrernme' The Comnission wes set up to review elternative epproprietetechnologies, to consider the role of chernotherapy, to essess the possible effects of ocP erea extensions, to determine the extent of eventuallyincorporating other vector-borne diseases in Progrgmne operations, to recorunend reseerch in those respects, and to determine what national andinternationel structures were required for successful continuation of oCp and whet treining was needed for the purpose. rn other words, the Conunission wes asked to consider a number of specific aspects of the Programre rather then to ProPose a strategy, inasmuch as its terns of reference did not call for aninplementation schedule, for en estimetion of future needs in the way of resources or for financial forecasts in that respect. 2.5 The Independent cormtission recorurended thet the progranune continue inits present form, including extensions to the west and the south, and considered in some detail a number of technical aspects of progranrne operetions, with perticular emphasis on the feasibility of alternative nrethodsof applying larvicides or insecticides, the place of chernotherapy in thefuture, and the gradual delegation of responsibility to the earticipating countries as part of a nrultidiseese surveillance system incorporated into nationel primary heelth care systems. 2.6 Although sone of the elenrents inherent in e long-term strategy for a ProBramne Iike ocP heve thus been considered in previous reports, none ofthen, with the partial exception of the PAG report, h.rre constituted long-temrstrategy proposals, nor, indeed, were they supposed to do. Nevertheless, theviews expressed and the reconunendations made, in particular by the Independent conunission, have been inportant elements in devising th; ocp Lont-TemlStrategy. 3 Purpose and use of the Strate:v The nein purpose of preparing and edopting a Long-Term Strategy isthe Progrermre's stetutory bodies and nanagement iith a aescriplion 3.1 provide toof ocP/84.4 4 the future course of ocP operations as planned to reech the overall progranrme objective and thereby achieve lasting success, outlining the conrbinations of verious technicel epproaches end the manpower, supplies and equipment required, as well as estimating the corresponding costs at different points intine. 3.2 The aveilability of an agreed StreteBy, containing the elementslisted, will enable the Participating Countries to orient and develop their onchocerciesis control ectivities, including those for which they become responsible under the devolution process, in eccordance with a set medium-term/long-term schedule. At the ssne tirne, it will a1low the Donor cottmunity to meke tentative long-ternr plans for contributions to the Prograrnme, in the light of the activities plenned, the progress and results expected, and the estimeted costs. 3.3 The OCP management and Progremoe staff wiIl use the Long-TermStrategy as a framework for preparing short-ternr and nediun-term proBrarrlnes and assigning the internrediate goals to be considered in future evaluation exercises. Furthermore, once approved, the component parts of the strategy will beconre the subjects of separate "plans of action,.. 3.4 An irnportant aspect of evaluation will be the analysis of futurebudgets in relation to the Stretegy's finencial forecests. To make this eesier, the presentetion of LTS projections and of the budget estimetes in the Director's Plen of Action end Budget docunrent will have to be brought into line with each other, 4 Conceptual cons iderations 4.1 One feature of a strategy that must be defined frorn the outset is the tisre spen it is neent to cover, in other words when it is to begin and to end. Although a long-term strategy is usually concerned with proposals for the feirly distent future, it would seem reasonable in the case of OcP to bring, in also short-term and nredium-term elements, i.e. projections covering the not-so-distent future thet will Iay the foundation for successful implementation of the Strategy. It can thus be erpected that the Protraxme will undergo some fairly significant changes in its operations before 1986 which will have a bearing on the Lont-Tenn Strategy. Furthermore, during 1985, the final yeer of the Progrennre's second financlal phase, consultations will be held with a view to ensuring continuing support and finencing for the third phase (1986-1991), end here the Lont-Tenn Strategy will serve e very useful purpose. The starting point of the OCP LonB-Tenn Stretegy hes therefore been set as 1986, the first year of the third financial phese. 4.2 In determining the end point of the Strategy, it must be considered whether the Long-Term Strategy should relete only to the period of ocP operations proper or continue to apply efter they have ceased, i.e. whether it should not also cover the post-ocP period unt i 1 the Progranune' s overall objective, as defined by the Expert Advisory Comtittee (EAC), has been reached, nanely "to eliminate onchocerciesis as a disease of public-health and socioeconomic importance throughout bhe OCP area and to ensure that there is no recrudescence of the diseese thereafter". Although this objective relates specifically to OCP, it would seem to heve been Ef,c's intention to include in the time required to reach it the period after the end of the Progranune during which Participating Countries will carry out maintenence activities on their own. fhe end point of the ocP Long-Tenn Strategy wi11, therefore, coincide with the attainment of the Progranune's overall objective, even if this involves operations carried out under the Strabegy but exclusively on e netional basis. In other words, the Strategy will remain in operation after the end of OCP. a r ,5 ocP/84.4 4.3 In view of the neture of the Onchocerciesis Control Protreilne, the Strategy and the plens of action into which it is trenslated (see parag,raph 3.3 above), will need to renain flexible enough to respond to new developnents directly relevant to OCP operetions. The Lont-Tenn Strategy nust therefore not be seen as e straightjacket inpeding the operational freedom of bhe Programte managenent, nhich nust continue to enjoy a greet deel of letitude in decision-naking in order to be able to cope with ever-changing situations end unforeseen developments within the Progranme aree. 5 ferms of reference and backEround documentation 5.1 In accordance with the JPC decision that a Lont-Terrn Strategy be prepared, the Comnittee of Sponsorin6 Agencies (CSA) worked out e set of "ferms of Reference" (TOR) for this exercise (see Anner 1). 5.2 The reader is referred to the LTS "Infornation Docunentri (OCP/LTS, 29.06.84) for any beckground information required. c PROCEDURES FOLLOTfED I}I PRBPARIIIG LONG-TERX STRATEGY OPTIONS 6 Sununarv of procedures 6.1 The present document has been prepared by the management, operationel and scientific steff of the onchocerciesis Control Programre with the assistance of a Consultent Coordinator. Ful1 use has been made of a nurnber of basic documents, such es the report of the PAG llission, the tJllO Eveluation Report on OCP Activities and Acconrplishments during the Years 1974-1979, and the report of the UllO Independent Conurission on the Lont-Terr Prospects of the Onchocerciasis Control Progrmne, as well as of published and internrl OCP docurnentsl and scientific pepers. Another useful source of information hes been the Scientific Review of the Progranune2, which surunarizes in one document the operational, managenent and scientific experience of OCP, as well as the results of OCP-supported studies and research. 6.2 The following peragraphs outline the procedure followed and the steps taken in drawing up the Strateg,y proposel. 7 Definition of operational phases 7.L An importent element in any OCP planning end programning exercise is the current end projected operational situation within the Prograrmre aree. In this connection and on the basis of oCP erperience, the following five operational phases heve been distinguished: Erploratorv phase: this covers the period during which epideniological and entomological beseline data and inforrnetion on potential socioecononic developnent are collected end exploretory and feasibility studies ere conducted, without any financial or other conrnitment to cerrying out preparatory and/or control operations later. Preparatory phase: this covers the period during which information and deta necessery for the planning end programning of en ocP operation (including epidemiological and socioeconomic baseline deta) are being collected end norrnelly leads direct to the launching of the ettack phase in eccordence with e set schedule. 1 Arnong which the report on the "senegambia Project' (vBc/81.2) and the "Proposcls for a Uestern Ertension" (OCP/E2.3) have been particularly useful. 2 To b" published under the title of "Ten Years of onchocerciasis Control in lJest Af rica". ocP/84.4 6 Atteck phese: this covers the period during which vector control operations are carried out regularly and wi thout interruption; according to OCP experience, it will norrnelly last three yeers unless the entomological surveillance system finds blackflies sti11 present in epidemiologically dangerous numbers, in which case a longer period will be necessary; during the ettack phase intensive entomological surveillance is conducted. Consolidation ohese: this covers the period during which vector control op""atton. """ no longer carried out regulerly and without interruption; control meesures are determined entirely by the findings of the surveillance systems, which renain unchenged fron the ettack phase; it will last for two to three yeers unless the finding,s of the overall surveillance systems indicate that disease transmission is continuing; resettlement and socioecononic developnent nray be encoura6ed as from the beginning of this phase. l{aintenance phase: this covers the period during which vector control ceeses to be a constant component of OCP operations, but is confined to any foci of blackfly reinfestetion that may occur; the entonological surveillance system is gradually reduced and concentreted in the areas knorn to be potential sites of reinvasion end local breeding. The area will remain in the naintenance phase until epidemiological evaluation indicetes that the prevalence of human infection is sufficiently low to prevent recrudescence of the disease in case of reinfestetion of bhe aree by blackflies end thet there are sufficient safeguards against the risk of the disease being iurported from outside the 8ree, in which case vector control and chemotherapy, when available, would be resumed in the event of locel reaPPearence of infective bleckflies. For planning purposes the duration of the neintenance phese has been set at ten yeers. ttris would seen reasoneble in the light of recent findings which suggest that the lifespan of the female Onchocerca volvulus is on the averate eleven yeers. Given that the combined attack/consolidation phese lasts five years, an additionel ten years'meintenence should prevent the risk of recrudescence of the diseasel. 7.2 The responsibility for operations will rest with the Progrenmre during the exploratory/preparetory, attack and consolidation phases, after which it wiIl gradually be taken over by the Participating Countries concerned, so that OCp support wilI ceese efter the first five years'maintenance, following, which overall supervision and operationel support, when required, will be provided by an OCP successor body (hereefter referred to es an Inter-Counbry Facility). Thus, the first half of the nraintenence phase corresponds to the period when Perticipating Countries will gradually be assuming fulI responsibility for rnaintenence activities within their territories. this is also the period when resettlement is encoureged through the support given by netionel authorities end, as and when required, by OCP, to socioeconomic development. It should be stressed, however, that this phesing of the devolution process is suggested for planning purPoses only and that what actually happens will vary sonewhat according to 1ocal conditions. 1 obviously, the final operational decision that the meintenance phase is over must be taken on epideniological grounds in every case. Once an OCP Operationel Zone (see paragraph 8 below) is thus declared as heving completed its maintenance phase, it would be safe to let non-infective bleckflies re-enter the zone. I 7 ocPl84.4 7 1 .3 Certeln charecteristlcs n Figure 1. of the operetionel phases ere shorn Flrure 1 Characterlrtics of the Operrtlonel. Phases FACTORS ATTACK COITISOLIDATIO}J TIAIIITEIIAIICE Durat ion 3 years high high >1 000 > 100 high 2-3 yeers rnediuru mediun <1 000 < 100 decrees i ng occes ional 10 yeers lor Iow <100 <10 dec rees i n6 I i nearly no Frequency of spraying operat ions Cost/100kn river(surveillance & lervi c i di ng ) ABRl ATP2 Infection load Transmission of infection yes Human resettlenent Devolut i on not sefe premeture poss ible prenature to be encoureged feas i ble The heve been indications est imates . velues atteched to the seven factors listed deterni ned on the bas I s of prog,ranmegiven against the last two fectors are above the stippled llne erperience, while the nore in the nature of 8. Delinitetion of OCp Operational Zones (002s) 8'1 The present ocP aree presents e rather heterogeneous picture es far asentomological date, epideniological findin6s and prograrm- operetions areconcerned. In order, therefore, to establish a brsis for rational planning.the Programne erea (includlng thet of the Southern Ertension) has been divideOinto nine 'roCP operetional Zones (ooZs)'r. Eech ooz represents e 6eogrephicelarea throughout which present entornological and epidemiological "onaltion" "t"relatively uniform and past and present ocP operations heve followed e sinilerpettern. 1- .rtonuel .Bitin: Rete: The nurnber of blackfly bites a person would receiveif he or she were to sit et the river bank for eleven hours a dey, 365 days ayear. fhe level of tolerebility has been set et en ABR of 1 000 (m{o, 1977). 2 Annual Transnission potential: The nunber of infective lerveehove been transmitted to the person under r above by the bitinglever of tolerability hes been set et en ATp of 100 (tJllo, 1977). uhich night fIies. The The levels of tolerabiltty erpress the upper threshold below which oCpfield experience has shortn that gerious eye-lesions ere unlikely to occur. ocP/84 .4 -8- It cen be expected furthermore, that each OOZ will continue to display this unifornitv end similarity. A tenth OCP Operational Zone corresponds to the lJestern Extension area. 8.2 The map in Figure 2 below shows the boundaries of the ten OCP Operational Zones and the operat.ional pheses in which they are currently (1984) classified. Figure 3 on the following pate presents in tabular forn the charecteristics of each of the ben OOZs. Further details can be found in Annex 2. In view of t,he frequent references to Figure 2 in the remainder of the text, the map hes been reproduced es Annex 6 so that it can be readily consulted by the reeder. Figure 2 OCP Operational Zones and Corresponding Operational Phases Exploratory (ZOP 10.1) Prcaararory (OOZ 09) Artack Consolidatron IZOP 02,03, 04, 05, 06, 07, 08) M.rntenanc? IOOZ 01) E P A c M o ---__p--_______ ___ _ __ _i 0 -( I l, SITUATION IN 1984 01 /)- oi M ,-' , c, ( I ,1 (lr c \\ -)- @.rC( ( J,', .\ .( t( I I I s I I' 9Figure 3 therec-lerigtlcs of OCP Operational Zones (002) ocP/84.4 ocP OPERA- TIONAL ZONES AREA 000 p|2 OPERAT- IONAL PHASE2 1984 ABR/ATP (HIGHEST VALUES 81-83 ) KI{ OF RIVER TH.f,T HAVE EVER BEEN TREATBD SPBCIES (S-SAVANITIA F-FOREST) REII{VA- SION RESISTAIiICE TO ORGANO- PHOSPHORUS LARVICIDES 01 o2 03 04 05 ?75 60 7? 79 134 2 490 3 045 3 425 <100 <100 <100 >100 <100 >100 >100 <100 >100 >100 >100 <100 ++ ++ SOURCE 70 90 19 9 H c c c c c c c s s F s F s F s F s s s <1 <1 <1 >1 <1 >1 >1 >1 >1 >1 >1 000 000 000 000 000 000 000 000 000 000 000 000 + + ++ + ++ 06 o7 08 1 550 2 395 2 810 38 2L 85 ++ ++ <1 09 10 111 440 5 830 22 0001 >1 000 >1 000 SOURCE SOURCE +(?)P E >100 >100 SF SF 9 Deterrninetion of options 9.1 Various options were then suggested after a number criticel inportance for en oCP stretegy (listed in paragraph exenined with e view to determining what variables should be taken 10 Forecasts of the wey in which operetion will deyelop 10.1 On the besis of bhe average duration of each operational down in paregraph 7 above, a prediction was nade of the wey in option would develop, phase by phase end year by year, in eech OOZ. 11 Cost estimation 11.1 The various options have been costed by estinrating of activity" required within the OCP Operational Zones et the particular operetionel phase in protress in each Obviously, the resultin6 estimates should not be seen as reliable "orders of mag,nitude". of issues of 13) had been into account. phase which 1a id eech the nunber of "units a given time and in OOZ at that tine. more than reesonably Ll.2 lhe following "units of activity" have been used for the purpose of cost estimation: 1 tot.I length of rivers in tJestern Extension area operations will be deterrnined by erploratory studies. The ertent of eventual 2 B, Erploratory; ll: lleintenence. P: Preparetory; A: Attack; C: Consolidetion; ocP/84.4 10 For the ProPosed StreteBy' expenditure) are maintained at 100a until phase. During the fourth phase they are by 1997. Entonglogicel surveillance: "the surn total of activities carried out UV one OCP sector and/or sub-sector during one year"' Aerial operations: ,.the sum total of activities required for aeiiaf operations per 100 km of river during one yeer"' Epidenrioloqicel eveluetion: "the sun total of ectivities cerried out uv tte ocP epiderniological eveluation ErouP during one yearr'. Socioecononic development support : "the sum total of ectivities @Psocioeconomicdeve1opmentgroupduringone year{. 11.3 On the basis of the total length of rivers in each 002 (see Figure 3) and OCp,s operational erperience, the total nunber of units required annually for each option has been worked out. A determining factor in the process has been the operational phase which the OOZ is expected to have reached at e given time, if the option in question is selected (see below). 11.4 Cost estimetes ere based on three mein elements : fixed costs, variable costs, and the cost of research and training' 11.5 Fixed costs ere the basic continuing professional, technical eanrinistrative support costs of the Protrarune plus capital expenditure' element includes the cost of epidemiological eveluation and of support socioeconomic develoPment. end This for fixed costs (excePt for caPitel 1991, the end of the third financiel erpected to decreese gradually to 304 11.6 Veriab costs are those of aerial operations and the entomological were derived from attack phase forsurveillance netuork. Cost figures for aerial operations 1982 data, and were estinated at Us$ 23 500 during the each 100 kilonretres of river covered. 11.7 past date heve shown that the cost of eerial operations during the consolidation phase is roughly one-half the cost during the ettack Phase; bhe cost of the maintenence phase is about 2OA of that of the etteck phese during the first yeer, dirninishlng to 5a during the fifth year of maintenance. 1t .8 The entonologicel surveillance network is made up of sectors and subsectors. The averaBe annuel costs of a sector and e subsector, celculated on the basis of actual expenditure in 1983, were US $ 277 000 and US$ 163 000 respectively. The number of sectors and subsectors wes reduced es the OCP Operational Zones moved from the attack to the consolidation phase and on through the maintenence phase in accordance with the pattern observed in Upper Vo1ta. 11.9 The calculated cost of aerial operations end entomological surveillance includes the 5th yeer of maintenance only' 11.10 Reseerch end trainins costs cover applied reseerch, the chemotherapy research project and training. The leve1 of estinrated expenditure for applied research conrplies with the directive frorn the Expert Advisory Conunittee thet future expenditure should be maintained at its present 1eve1, at least through the third financiel phase. Estimeted expenditure for the chemotherapy research project Eoes up to the end of 1988, before when a decision will have to be nade concerning additional funding. 11 ocPl84.4 11.11 All estinretes are besed on the value of the US dollar in 1983. It ls recognized that the fectors such as inflation, the availability of e drug and devolution will effect the costs of the Progranune. However, it was felt that uncertainties concerning these factors were too great to be dealt with reelisticelly at the rnonent. L2 Selection of the best option for the Stratetv L?,L The finel step in the procedure was to compare the operational end financial implicetions of the various optlons in order to determine which one, if implemented, would satisfy certain operetional criterie and enable the ProEramne to attain its overall objective. 13 Issues of critical itnportence for selecting end puttinl into effect en OCP Lons Term Strategv - Blackfly reinvesion - Resistance to larvicides - Forest speeies of the blackfly - "Forest type" of onchocerciasis - Epidemiological trends - Chemotherrpy - fnununo-diagnostic test - Devolution. - Adaptation of control methods and the addition of others. D. PROPOSAI FOR AI{ OCP LONG-TERI{ STRATEGY 14. Possible options and selection of Stratetv proposal 14.1 In deciding on the veriebles that could be used as a besis for the options to be taken into consideretion when the proposed OCP Lont-TennStrategy wes bein6 determined, a thorough analysis wes made of the issueslisted in paragreph 13 as being of critical inrportence in this connection.The conclusion reached wes that reinvesion constituted the most inportantproblem for the future of the Progrsme and that consequently the decision asto whether or not to cerry out vector control operations in the Extension areas should be a decisive factor in selecting a perticular option. The cognate problern of whether or not to protect the populations in these ereas would elso need to be given careful consideretion in this connection. L4.2 The second issue with inportant operational irnpllcations was that of whether or not to ettenpt to control forest bleckfly species. fhis frctor restherefore included in the identification of options based on the no-extension scenario (see Anner 3). 14.3 Five options were thus distinguished Option 1 Option 2 Option 3 Option 4 Option 5 OCP operations unchenged; no control in Extension ereas No control of forest species; no control in Bxtension ereas Extension to the south; no extension to the westl Extension to the west; no extension to the southl Extension to the south end to the westl 1 Option 3, 4 and 5 exclude control of forest vector species ocP/84.4 -t?- ifth year of maintenenceirst what tine the OoZs would be the s i tuation as et the strong and of Progranune 14.4 In order to predict for eech option atentering and/or concluding operational pheses,beginning of 19861 was predicted to be as follows: 002 01 ooz 02 002 03 ooz 04 002 05 002 06 ooz o7 002 08 002 09 in firs in firs yeer yeer yeer year year yeer 1rs 1rs rrs inf inf inf inf inf t t t t t of of of of of of meintenance consol idat i on consol idat i on consol idat i on consol idat i on consol idat ion z Lo.Lz z Lo.22 z to3? 00 00 00 in second year of meintenance in first yeer of attack in first yeer of atteck. one yeer before beginning of attack (in 19g7) two years before beginning of atteck (in lggg) fhe average duration of the various Has then applied to each 002. In thet an operational Zone in which consolidetion phase. operatlonal phases (see paragreph 7 above)doing this, eccount was taken of the fact reinvesion occurs regularly reneins in the 14.5 Figure 4 below surmarises in tebular forn the operational consequences and cost irnplications of each of the five options Iisted inparagraph 14.3. The forecests end conclusions arrived at ere based on the more detailed analysis conteined in Annex 4. The costs given under',FinancialItuplicetions'r refer to control operations only and exclude costs of research and training. lleintenance is costed for the first five years onry. 14 . 6 In conforrni ty wi th the Independent Conuri ss ion, s well-reasoned reconunendation not to consider the cessation operations, no zero option has been put forward. 1 several ooZs will be in the sane operational phase in 1986 and it might therefore have been thought thet they could be consolidated into a single OOZ. This, however, would not be feasible inasmuch as each OOZ has its ovrn characteristics, so that the course it followed under various options would differ from thet of the others. 2 ooz 10 : Llestern Extension area. OOz 10 is to be divided into sub-zones (10.1' 10.2 and 10.3) in which OcP operations will corulencegradually on e yearly basis; the attack phase in 10.1 wirl stert in 1986. _ 13 _ ocP/84.4 FiEure 4 ocP LTS options end the rmorications of their rrnprementetion 14'7 The bar-chart in Figure 5 on page 15 shows e conperetive projection ofthe operetional development of the five options zone by ione. rhe projectionsfor options I and 2 ace identical, assuming no control of forest rp""i", of thevector (option 2t. The maintenance phase, when applicable, is rho*n as tsodistinct five-year sections of which the first (continuous green) corresponds tothe period of devolution, while the second (hatched green) depicts the last fiveyears of meintenance, when ocp support, as such, is no longer required (seeparagraph 7.2). 14 ' 8 It is estimated that the cost of the operational component of theProgranune i.e.excluding the chemotherapy project, research and training, duringthe second financial phase (1980-1985) will be us$ 94.5 mi1lion. From Figure 4,it cen be seen that the operational component of the Strategy, option 5, wouldcost only a moderate 202 more in the third financial phase, (19g6-1991) and thatthis cost will drop to only us$ 43.6 rnillion for the fourth financiel phese(1992-L997 ) after which OCp would ceese operations. 1 Except that the entomological surveillanceSouthern Ertension area would be abolished. network establ i shed in the 2 thi. option is hypothetical insofar as there could be no control operationsin the west without fuIl operations in the south, the latter having been approved by JPc pending the availability of additional larvicides, while theformer sti1l require formal approval of the ConmitLee. Opt ions Operetional Implicat ions Fi nanc i al 1 i cet ions(in rnillion US dollars) Option 1: Progranune operat ions unchangedl(no control in Extension areas). - Reinvasion in east and west of Prograrnme area. - Option incompatible with attainnrent of OCp overall obj ect ive - Financial Phase IfI ( 1986-1991) : 68.7 - Financial phase IV(1992-1997): 58.1 - Fron 1998: US$ 9.5 rnillion a yeer indefinitely. Option2:Nocontrol of forest species; otherwise no changel(no control in Extension areas). - Reinvesion in east and west of Programne aree - Option inconpetible with attainment of OCp overall objective - Finencial Phase III:64.6 - Finencial Phese IV : 55.5 - From 1998 : US$ 9.1 ruillion e yeer indefinitely. Option 3: Extension offull OCP operations to the south (no control in tJestern Extension area). - Reinvesion in the west of the Protreme aree - option incornpatible sith attainnrent of OCp overell obj ect ive . - Finencial Phase III: 69.6 - Financial Phase IV:42.6 - Fron 1998 : US$ 4.9 rnillion reducing year by year down to 3.9 million by 2003. option 42: Extension of fulI OCP operations to the west (no control in Southern Extension areal). - Reinvasion in the eest of the Progranrme area - Option incompetible with attainnrent of OCp overall objective. - Finencial Phase III:101.0 - Financial Phase fV: 38.0 - From 1998:US$2.1 million reducing year by year down to 1.3 million by 2003. Option 5: Extension offull OCP operations to the south end to the west. - No reinvasion - Option compatible with attainnrent of OCp overall obj ect ive . - Financial Phase III:113.0 - Finencial Phase IV: 43.6 - No costs beyond 1997 when Progremne operetions ceese. ocP/84.4 -14- 14.9 On the other hend, operational costs for Option 4, extension to the west but not to the south, would require a 7Z increase over the second phase; for Option 3, extension south only, there would be a decrease of 261 end for meintaining the status quo Option 2 without extensions e decrease of 3*. The operational costs pertaining to the fourth financial phase would for the three options be at the 1evel of or exceed those of option 5. Thereafter, control operations would have to be continued for an indefinite period without the Protramne ever reeching its objective. 14.10 As a result of the ebove analysis and the conclusions emerging from it, Option 5 is proposed es the basis for formulating an OCP Lont-Teml Strategy. 15 The OCP Long-Term Stretesv proposal : pro-iected operetional development 15.1 The six maps on peBes 16 and 17 (Figure 6) project the way operations will develop in the ProBramne area as e result of inplementing the Strategy. Eech nap depicts the situation during the first year of a bienniun, starting fronr 1986. The colours used heve the same meanin6 as in Figure 5, L5.2 The figure below reflects in more detail the projected development of Protrarme operations towards the meintenence phase: Firure 7 Teble showin: the Gredual Entrv of the OCP Aree and of its Rivers into the ltaintenance Phase Area Rivers 1OOO kr2 a of total Kn a of total 1986 198E 1990 7992 1994 360 764 764 1 165 1 315 27 58 58 89 100 5 770 18 675 18 675 39 005 46 505 L2 40 40 84 100 15.3 The table below shows by two-year periods the greduel reduction of the area in which atteck and consolidation operations are carried out. Fig,ure 8 Table showing the Graduel Reduction of the OCP Aree and of Rivers in the Attack and Consolidetion Phases Area Rivers gn2 a of Total Km a of Total 1986 1988 1990 t992 1994 595 551 551 150 o 45 42 42 11 o 25 735 27 830 27 830 7 500 0 56 60 60 16 0 (text continued on page 19) 7 ,/, Z 2 ,4 ,Z ,n OPTIONS 1 & 2 AS IS OPTION 3 EXTENSION SOUTH OOZ :01 02030405060708 01 0203040506070809 1 986 I 987 1988 1 989 1990 1991 1992 1993 I 994 1 995 r 996 1 997 1 998 1 099 2000 2001 2002 2003 '1, ,u Z ,,, -15- Figure 5 Projected operational development by OOZs ! Preparatory phase I Attack phase t Consolidation phase !M.intrnrnce phase: (1-5 years) @lirrint n"rce phase: (6-10 years) n 'n 7, n ,u 7 ,2 7. OPTION 4 OPTION S=THE STRATEGY EXTENSION WEST EXTENSIONS SOUTH AND WEST l0.r 10.3 10.1 10.3 0l 02 03 04 05 06 07 08 10.2 01 02 03 04 05 06 07 08 09 10.2 Z ,, 7. ,u .,ll ,Z ,Z ,u ,n, ,n ,u 'ru v, ,Z 7 ,1, ffi ffi n 2Zv. v. ,,4 wHo 84893 ocP /84.4 1 986 1 987 r988 1 989 r990 1991 1992 1 993 1994 1 995 r 996 1 997 1 998 1 099 2000 2001 2002 2003 -16-ocP /84.4 Figure 6 _Efojectg!-_9 pqleli onal_deve !o pgen! - lhg_Stglesy_ ! Rrrn"r.tory phase ! Attack nhase ! Consolidation r i41il,::?3* %w\t;::,tr SITUATION IN 1986 SITUATION !N 1988 SITUATION IN 1990 o} The boundaries of the three subdivisions in the Western Extension area have been drawn for illustrative purposes only. 0 r00 ?00 {0 (m @ l\ 1 IT ///rr -Js\) \ 6., I l; \ @ E3, @J B. -i I\i\ r' ..)" ,l ;, V q ) 1 j ) J @ J -17 - ocP /84.4 Figure 6 opglationa I development -_!!9._Sttg!ggy_ ! Consolidation ri{:fli?:?t}* %Ay62\t',,"tr f::ri-Il-l 1O years maintenance I::ti]:::::l COmplgted The boundaries of the three subdivisions in the Western Extension area have been drawn for illustrative purposes only. OoZs 10.2 & 10.3 will enter second half of maintenance period in 1997 and ] 998 respectivily, when remaining areal has already had 1 0 years or more maintenance. lExcept OOZs 09 and 10,'l SITUATION IN 1992 SITUATION !N 1994 SITUATION !N 1996 q o i I ]'ll . q{. f "J/ i@ JI 2{..-- )-4

-19- ocP/84.4 15.4. Perticular attention is drawn to the projections in relation to the Hestern Extension eree (OOZ 10). In drawing up plans for OCP operations in this aree under the Strategy, (see Annex 5), several approaches were considered, including that of a i'pincer movement" starting in the west (in order to eliminate the risk of reinvasion in OoZ 1O fron the outset), with a sinultaneous move frorn the present OCP border in a westward direction(designed inter alie to continue the protection of this border zone). However, an analysis of the operational implicetions of these various approaches showed that gradual extension to the west in three stages (002s I0.1, 10.2 and 10.3) was the most feasible approach from the logistic point of view. 16 The OCP Long-Terrn Stratesy proposal : implications of the projected developnent of operetions 16.1 As can be seen from Figures 7 and 8 the Strategy aims at bringing Progrenrne operations fairly rapidly into the naintenance phase throughout the whole area. As early as 1988 all OCP operational Zones, except those rnaking up the Extension areas (09 and 10), will be in the rnaintenance phase, OOZ 01 having already been so for six years, ooz 02 for two years and 002 08 for three years. By 1993 the whole Protramre aree, including the Extensions, will have entered the maintenance phase and the original OCP area (OOZs 01 to 08) will have been in that phase for five years or longer and consequently will nolonger be dependent on ocP for support ( see paragreph I .zl . The last operational Zone (10.3) to complete the first five years of naintenance will do so in 1.997. L6.2 The operational projections further suggest that the transfer of oCp aotivities could begin in the comparatively near future, at least in the core of the original Progranune area (002 01), where devolution rnight be conpletedbefore the end of the current decade, since the entire process is expected to coincide in time with the first five years of the maintenance phese (seeparagraph 7.2\. rn the remaining parts of the present (1994) ocp areadevolution would develop gradually from 1988 onwards and be concluded in 1992;it would be completed by 1995 in the Southern Extension area end by 1997 inthe Western Extension area. 16.3 This devolution schedule can obviously be no more than indicative,but it could be assumed, very tentatively, thet the continuation and eventuel cessation of direct donor support to Prograrune operations would to some extentbe guided by the five-year devolution periods suggested for various perts ofthe OCP areas in the preceding paragreph. 16.4 It should be stressed, however, thet if the devolution process is todevelop in a satisfactory and responsible menner, early preparatitns will haveto be made for Participating Countries to essune responsibility for OCp meintenance activities. It might therefore not be unreesonable to sugtestthat members of the Donor conununity may wish to support eerticipa[ingCountries as required in the strengthening of their infrastructure end oftheir management capebility, in the actual implementation of the devolutionprocess, end in the conduct of maintenance operations during the second helfof the naintenance period when direct Protrafine support will have ceased. L7. The OCP Long-Tern Strategv proposel : operations 17.1 The methods of surveillence, control and epideniological evaluationwill continue unchanged, although with certein modifications of the existinginfrastructure. As will be seen frorn the definitions of operational phases in ocP/84.4 -20- ParegraPh 7, the structure will remain unchanged throughout the atteck and consolidation phases. lJtren en OCP Operational Zone enters the meintenancephase, however, its surveillance network will be modified. Responsibility for sectors and subsectors will devolve on the Participating Countries and there will be a graduel reduction in force. The remaining staff will become highly nobile, whenever possible nakin6 ful1 use of lighter and more econonical means of transport than has hitherto been the case, and the fixed establishments wiIl be reduced to the minimum conpatible with the leve1 of surveillence which OCP erperience has shown to be necessary for the maintenance phase. L7.2 l{ore specifically, entomoloBicel surveillance will be focused on i'risk sPotsr', i.e. those stretches of river where experience has shown that blackflies ePPear eerliest, either owing to reinvasion or to loca1 breeding, and/or in the highest concentrations. Also, inproved Bellec blackfly traps will be used extensively as en "early warning" system, if the current field tests prove them to be operationally effective. 17.3 The automatic tneesurement of hydrological conditions and the trensmission of the resultant data to the OCP operational base via satellite ere currently being tested for operational reliability end cost-effectiveness with a view to their possible use within the Prograrme aree. L7.4 As the Progrsnne noves towerds the maintenance phase and devolution becomes e reality, there will be an increasing need to test, adapt end where necesserlr epply additional control methods such as the use of adulticides, ground control operetions and the encouraBenenb of settlenrent patterns thet seenr 1ikely to reduce the risk of disease transmission. Although larvicide application from the air is sti11 the control nethod of choice, at least for the time being, operetional reseerch into other means of control and more adaptable types of technology, which would be of perticular value in meintenance operations, will continue to be given the necessary support. 17.5 The intent of the Progranme has been to control savanna vectors of onchocerciasis. However, in the south of the Ivory Coast operations have also included the control of forest species of the blackfly, in particuler those which spread into the sevanna area. Beceuse of resistance, these operations have become a major drain on OCP resources owing to the need to use Bacillus thurinsiensis H-14 as a larvicide, which involves disproportionately high costs(estinated to average Us$ 1.5 million per year). 17.6 The particuler attention given to the issue of soubrense/ sanc control is, to a large ertent, a reflection of the situation as it exists today(1984), when a conperetively high proportion of OCP resources ere used for controlling, a veetor whose role as a trensnitter of debilitating onchocerciesis is unknown. In future no separate etternpts will be nrade to control the forest blackfly species unless the research designed to elucidate the role of the forest species in the two forms of the disease and their respective significance in this regard produces conclusive evidence that mekes it necessary to reconsider the situation. (See also Annex 3). However, where necessery, the sources of savanna species located in forest areas will be controlled. 17.7 Furbhermore, it cen be expected that the aveilability of two edditional lervicides, a condition for inplementing the Strateg,y, nright in any case help to some extent to bring the forest species under control, since the new products are 1ikely to be equally effective against savanne and forest species and the two Broups practically always appeer in association with each other, ercePt in certain forest regions. -21 - ocP/84.4 17.8 The generel impression gained fron clinical and epidemiological field studies is that the "forest type" of onchocerciasis causes 1ittle oculer involvement and so should not qualify for control per se. Again, intensified studies are being conducted in order to confirm these findings. 17.9 The present ecological surveillence protocol will continue to be used and the coordineting and supporting role of the Ecological Group will remein of crucial inportence, in particular in the testing of new larvicides for adverse environmental effects and in the regular control to be cerried out in the Extension arees. 17.10 t ith the extension of ful1 OCP operetions into the Southern and tJestern Extension areas it will be necessary to consider the possibility of adapting the rnanagement structure of Ehe Protranme and the location of its operetional headquarters to the exigencies of the geogrephically extended control activities. Inasmuch as the OCP centres of gravity will move towards the south and the west, arrangements might have to be made for the establishement of e sub-headquerters closer to, or within, the lJestern Extension area, 17 .11 Such e reerrangement, in response to the need to decentreli se operational decision-makint, night also involve functional changes at the OPC heedquerters in Ouagadougou where facilities for supporting the devolution process could be gradually improved. 18. The Lone-Term Stratecv proposal : exoected result s and reoercussions 18.1 Reinvasion continues to be a serious problern in the zones near the eestern and western borders of the Protrelune. Almost 2OA of the present(I984) ocP eree is exposed to "exogenous" reinvasion from sources in Guinea,in the Southern Extension eree and possibly in Nigeria. The cost to the ProBrame of controlling the effect of reinvasion is considereble. Each year major larviciding operations are undertaken during the rainy seeson in the west and to a lesser extent in the east (estimated annual costs i US$ 0.7 million. and US$ 0.4 nillion respectively). 18.2 The exploratory aerial larviciding planned for 1984 in the Sankarani/Fie river basin area in Guinea has been approved for the specific purpose of confirming that the repeated reeppearance of blackflies in the present OCP area next to its western border is due to reinvasion from Guinea and can be effectively controlled. on the other hand, reinvesion fron Nigeria is much less of e problem, if any at eI1, in view of the prevailing winds. Fu11 control operations in the Southern Extension area should therefore result in the elimination of the problen. 18.3 The irnplementation of the proposed Strategy, by controlling breeding places from which continuing blackfly reinvasion tekes place, will make it possible to eliminate the threat of a recrudescence of onchocerciasis. 18.4 Although ful1 control operations in the Southern and lrestern Extension areas will help fundamentally in solving the reinvasion problem within the present (1984) Protreme area, an essential purpose of extending oCP ectivities to the south and west will be to protect the populations living in the Extension areas. Tn all about five million people will be added to the populations now sheltered by oCP control operations (two million in the south of Benin, Toto and Ghena and three nrillion in the west). It can be estimated that e littIe more than one million people are currently efflicted by onchocerciasis in the Extension areas of whom about 40 000 are blind. The benefits accruing to these populations will be of great importance to heelth and socioeconomic development in the areas concerned, ocP/84.4 -22- 18.5 Although findings fron epidemiological evaluation have been of lirnited irnportance in directing day-to-day control operations, they cen be expected to take on increasing importance in operational decision-rnaking as and when the cormunity loed of infection (nean microfilarial load of a cohort of adults) reaches IeveIs where chenges will becone significant for guiding control operations. 18 .6 Furtherrnore in view of Ehe recently denonstrated feirly repid reduction in the conununity load of onchocercal infection within the Prograrme erea and the likelihood that five years' attack and consolidation followed by ten years'maintenence will bring prevalence down to almost zero, it nay be anticipated thet the disease will disappear from the whole Progrsrune area by ZOO3. This result should be achieved considerably earlier in the Operational Zones not in the Extension areas. 18.7 It should be mentioned in passing fall in the conmunity loed of infection, it the Ieve1 of the Annual Biting Rate (ABR) 1evel of human infection. that with the comparativelY raPid will be necessary to reconsider that corresponds to a tolerable 18.8 In connection with the epidemiological effect of reinvesion it rnight be worth stressing that preliminary analysis of the results of investigating sone populations under effective OCP control but exposed to reinvasion by bleckflies, seems to indicate that even in such populations there is e discernible dornwerd trend in the conununity load of infection' although apperently less pronounced than that observed in populetions not "rpor"d to reinvesion. However, this is a highly localised finding.lloreover, should these preliminary results eventually be confirmed, the likelihood is that prevalence would renain at a leve1 which would not cornpletely preclude the reaPpeerance of the di seese, at least for bhe foreseeable future. In other populations living under sirnilar conditions, there has been no tendency for the conmunity load of infection to diminish and several children born since the start of vector control operations have already become infected. 19. The OCP Long-Te stretegv proposal : shift in the use of resources 19.1 Although only seven to nine yeers have elapsed since OCP operations comrenced in the original Protramne area and not more than five years since operations started in the south of the Ivory Coast, the results in terms of vector control heve been and continue to be highly satisfactory, to the extent that it hes been possible to reduce operations considerably. However, although the only Operetional Zone currently (1984) considered as being in the neintenance phase (Upper Volta, Niger and part of llali (OOZ 01)) constitutes 35a of the programre eree, the length of rivers therein represents only 104 of the total subject to control operetions. Furthermore, atrV substantial reduction in operational costs stenuning from O0Z 01 nroving from the attack and consolidation phases to the maintenance phase two years or so ago was masked by the increase of activities in the south of the Ivory Coest. lg.Z The implementation of the proposed Strategy will leed to inportant chenges in where and how Progranune resources are used. Present OCP operations are to a large extent directed towerds controlling reinvesion and that will continue until full control cor[nences in the Southern and iJestern Extension ereas . After two yeers' implementat ion of the proposed Strategy, the Operational Zones exposed to reinvasion will move from the consolidation into the maintenance phase, thus bringing ebout considerable savings in operations in the Oozs concerned (03, 04, 06 and 07) and allowing for a significant shift in the use of resources towards operations in the Extension arees. 19.3 all the at the costs, area. 23- ocP/84.4 Furthermore, as the proposed Strategy eims at gradually bringing , Operational Zones of the present OCP aree into the maintenence phese earliest possible dates, with consequential reductions in ProBranme substantial resources will be released for use elsewhere within the OCP L9.4 A third exanple of ensuring that resources are used to achieve thegreatest benefit is the intended concentration of OCP oPerations on the control of savanne species of the bleckfly rather than attenrpting exPensive control of the forest species, whose role in the trensmission of the disease is in eny case doubtful. 20 The OCP Lons-Tertn Stratesv oroposal : devolution 20.1 Devolution, i.e. the graduel essunption by Participating Countries of operetionel responsibility for OCP ectivities, should be seen as an integral conponent and normel development of the Onchocerc i es i s Control Progremne. OCP will eventuelly cease operations and the countries concerned will then have taken over whet renains of naintenence activities. A few operations on1y, such as aeriel larviciding in case of need, intercountry supervision and control and information exchante will be taken over by en Inter-Country Facility (ICF). At this stage, the Facility is merely a concept, and a very Beneral one et that; only later, when more is known aboutits functions and relationship with other inter-country bodies, will it be possible to stert thinking of the ICF's structure. 20.2 Although the lifetime of the Progranune as such wes originally estimated at twenty yeers, preparations for devolution have been under way for some time; indeed, certain activities such as hydrobiological monitoring are already being carried out by the governments concerned. A great deal of ettention has been given to ways and meens of planning and carrying out devolution at recent sessions of the Joint Progranne Comnrittee, the National Onchocerciasis Comnritbees and other stetutory bodies of the Progreme, as well as at meebings of national erperts called by the Director of the Progranme. 20.3 There is unanimous agreement between all parties within OCP that devolution must be planned and implemented very carefully so as to ensure thet it will help the Programne in eventually reaching its objective end at Ehe same time support the Participeting Countries in their efforts to strengthen their health care systems by ensurint thet continued onchocerciasis control and surveillance become part end parcel of netionel multidisease-control proBrarrunes integrated into primary health care systems. A separete plan of action for devolution, to be drawn up later, will include inter aIia, the steps to be taken in order to determine more clearly the conditions under which ocP activities may be transferred, a tinre schedule for further discussions with the Participating Countries concerning the potentielities forgraduel devolution within their territories, the action to be taken to establish nachinery within the JPC for controlling the devolution process(see the nert paragraph (20.4)), and possibly a tentative tirne schedule for the devolution process. 20.4 Any decisions regarding Lhe extent and nanner of transferring OCP activities to en individuel country are e netter of inportance not only to that country but also to the Part ic ipat ing Countries as a comnuni ty of partners in a common endeavour (and, indeed, to all the interested parties). It would therefore seem justified to suggest that future decisions in this respect be taken by the Joint Progranme Comrnittee. ocP/84 .4 -24- 20.5 It should be stressed thet es some of the operational Zones ereloceted in nore then one country, there wirl be e continuing need forinter-country colleboration when it cotnes to carrying out the devolution Process ' In this connection it is perhaps also worth mentioning that unforeseeable developments nright eventually lead to adjustrnents ingeographical coverage or the scheduling of operational phases in one or more of the OOZs' It is not enticipated, however, that eny such changes will be sogreat as to significantly alter the LTS forecasts. 20.6 In connection with planning and cerrying out the devolution process, the need for continuing training of the netional personnel concerned will makeitself increasingly fe1t. rrrespective of the menner in which theParticipating Countries eventually integrate transferred oCP activities into their respective health and/or health-related systenrs , the necess ity ofpreparing teaching material (e.g.operational menuals) to be used by national staff for training end reference purposes would seem to be rapidly becoming urgent. 20.7 Although the Progrenune has been successful in a few instances in involving the populations concerned in OCP surveillance and control operations, more needs to be known about the potentialities and opportunities for conununity perticipation, in particuler during the maintenence phase. With the devolution process due to conunence fairly soon, it is inportant that field studies on this subject be leunched in the near future with a view to determinint favoureble end unfavoureble factors. 20.8 Even if no hard-and-fast rules can epply to devolution es such, it would seem reasonable to relate its "intensity" and timing to the operationalphases. It could thus be suggested that the transfer of OCP activities would Bet under way at the end of the consolidation phase and be conpleted during the first half (5 years) of the tnaintenance phase. It should be stressed that this suggestion is made entirely for planninB purposes as pert of devising a Long-lerm Strategy.(See also paragraph 7.2). 2O.9. As already mentioned, it is not possible at this stage to foresee in eny detail how the devolution process will develop. This is a metter for consideration by the Participating Counbries thernselves in fuI1 collaboration with the Progranme and its various statutory bodies. An indication cen, however, be given of the nature and extent of the onchocerciasis surveillance and control ectivities that will be required during the neintenance phase and for which the Participating Countries will assune responsibility. At bhe start of the naintenence phase, the entomologicel situation in the Operational Zone concerned is characterised by zero, or very 1ow, blackfly catches at known potential breeding sites. Frorn the epidemioloticel point of view, the conununity load of infection is sti11 at a fairly hiSh 1eveI, although a downward trend hes begun to become manifest. The maintenance operations will therefore consist in keeping a close watch on the possible re-emertence of bleckflies within the Zone and teking the necessary neasures whenever required. Such meesures will consist in aerial larviciding within fairly limited ereas, with the possibility of eventually making use of adulticides and/or ground control in addition should operational research findings so warrant. 20.10 The role of epidemiological evaluetion will become increasingly inportant es the cornnrunity load of infection continues to decrease during the maintenance phase. Regular exenrination of indicator villages will continue at the Ievel necessery to keep a constant watch on overall trends in 25 ocP/84 .4 onchocerciesls morbldity ernong the populations concerned. llore speclficallythe results of epidemiolog,ical evaluation wl11 essist in deterrnining where and when the conurunity load of infection hes reached a level st whlch ABRs exceedin6 the currently established values can be tolerated uithout incurringthe rlsk of resuned disease transnisslon (see also pare6raphs 1g.5 and 1g.7). 20.11 obviously, the nenner in which onchocerciasis naintenence activitieswill be cerried out wllI differ fron one country to another, depending on thesiturtion. However, since the entornological surveillance networi is likely torenein in being rithin the Participating countries efter the pro6renune ceases operations, and since onchocerciasis surveillance wlll be grodualiy reduced in scope, it woul'd seem reasoneble to anticipete that the humen and meterial resources evailable within the network wiIl become increasingly involvedduring the neintenence phase in additional public heelth tasks in multidiseesecontrol, to be defined by the individuel countries concerned. Finelly, itnight be worth enphasizing that a reliable irmrunodiagnostic test would be ofparticular importence in the early detection of possible cases of recrudescent onchocerciasis near reinfestetion arees; cornbined with the use of an effective end convenient drug this would perrnit rapid elimination of recrudescent foci(see peregraphs ?2 end 23 below). 20.12 To give some idea of the implications of et reast one aspectdevolution, the teble below has been constructed to show operational Zone zone (002), the number of ocp subsectors ready for transfer toParticipating Countries concerned, end the calender yeer when this transfer erpected to take place (i.e. the sixth year of the neintenance phase): Fisure 9 Trensfer of OCP subsectors to Part cipatins Countries bv 0Z end Yeer of by the is ooz No. of sub- sectors 01 02 03 04 05 06 07 08 09 10. 1 LO .2 10 .3 3 198 7 1 1991 2 1993 2 1993 2 1993 1 1993 1 1993 1 1990 2 1996 3 1996 2 199 7 2 1998 2L The 9CP Lops Term Stratetv proposal : resettletnent and socioecononicdevelopnent. ?L.L The process of resettlernent is developing fast and on a firrn basisin the core of the original Programe eree, where onchocerciasis trensnrissionhrs now been interrupted for severel yeers. At the present tinre (I9g4) noglobal estirnates cen be given of the Progranune's effect in terms of the ertentto which people cen be resettled in river valleys and the surroundinE erees now freed from the risk of infection, except, perheps, to nention as en exemple that precticelly all previously infested arees in Upper VoIta cantoday be considered es safe for resettlenrent. The seme situation is also coming about in other parts of the Progranune aree and will be accentuated as a result of the interruption of reinvesion that will foIlow the implementation of the Strategy. 2L.2 No doubt agriculture wiII continue to be the nrein occupation of theresettled populations within the present oCP eree. In the t estern Ertension8re8, it cen be expected thet, in eddition to egricultural developnent,increasing efforts and energy will be directed towerds the mining industry, and that onchocerciesis control will make an inrportant contribution in this respect by opening uP erees for economic exploitetion that were hithertoineccessible owing to high onchocerciasis transmission retes. ocP/84.4 26 27.3 The indiscriminate cutting of trees and bushes purposes, often resulting in lasting ecological danage' and the[iffing of wild aninrals are potential ha'nrful effects of tlational administrations in the Progranme area are alert to these ere taking appropriate steps to prevent such damage occurrinB. 21.4 There is a specific reference in the overell objective of the Onchocerciasis Control eiogranune to elinrinating onchocerciesis as an obstacle to socioeconomic developnent. The Long-Term Strategy therefore provides for support to the participating Countries in respect of socioeconomic development .r-Ln activity to be clrriea out in close colleboration between the sponsoring ag,encies with the participation of other interested or6enizations end institutions. ZL.5 OCp will continue to collaborate with the Participating Countries in basic studies on the hunan and material resources that become available as a result of Progranune operetions within the countries concerned. 2L.6 The Progremne will elso fecilitate inter-country exchange of Iocal and netional erperience in matters of socioecononic importance releting to resettlenent. Relevant data and inforrnation will be collected, enalysed end distributed to the countries, which will thus have an opportunity of learning from one another's operational experience. 2L.7 FinallY it is envisaged thet Participating Countries 8s to the nost development of onchocerciesis-free zones' for donestic uncontrolled resettlenent. problens and OCP will be reedY to edvise the pronising ways of investing in the 22 2?.t The onchocerciasis chemotherapy Project, which is being carried in close collaboration with TDR1 and the pharrneceutical industry, conducting research aimed at providing the ProBremne with a drug cepable killing the parasite in hurnan beings. The ocP Lont Term StreteFv.proposal.,:.8v8.i18b.i]itv of e druR ffiscele selective population chenotherapv out is of ZZ.Z If a chemotherapeutic egent is to be developed thet would nake a significant contribution to the control of onchocerciasis in the Participatin6, Countries, it should preferably be an easy-to-disPense long-acting macrofilericide with no or negligible side-effects. A microfilaricide neeting these same criteria might also be suitable for mass treetment, provided thet it could safely be adnrinistered regularly (once or twice a year) for as long as the fernale worms are cepable of reproducing, i'e. ten or more yeers (unless the drug in question turned out also to affect the edult worms). Despite the relatively short time since this research project begen' one nricrofilaricide conpound hes alreedy shown some promise, 22.3 In view of the uncerteinty that attaches to the outcome of any problern-oriented reseerch, it is obviously extremely difficult to predict the irnpact on onchocerciasis control in the OCP aree of the eventual energence of a useble chenotherapeutic agent. A few hypotheses and their possible irnplications for OCp operations and the devolution Process will nevertheless be presented. 1 wrozut'tpp/IBRD Special Prograrune for Research end Training in Tropical Di seases . -27 ocPl84.4 22.4 Should rnass treetment turn out to be e distinct possibiltty by, say, 1988' the rnajor pert of the present Protre.mne eree would be in the maintenancephese: one 002(01) would have completed the first five years of thet phase. The new drug would therefore heve its impect essentielly during the devolutionprocees, except in the Extension erealr, where it would already be used as ln adjunct to larvicide spraying during the attack and consolidation pheses. It would also be necessery to measure the degree to which mass drug treetment niSht counter-balance the effects of reinvesion end therefore eventuelly be substituted for lervicide applicetion from the air. The possible effects ofthe drug, on the "forest type" of onchocerciasis and on old cases of thedisease are other subjects for investigation. 22.5 The effect on costs of an effective chemotherapeutic egent cannot asyet be estinreted, inesmuch as several of the deternining factors, such as thedrug's market price, its mode of application, the treatment schedule endpossible side-effects, ere stil.1 unknown. However, e special study on this aspect of the drug issue will be undertaken es soon es more is knorn about these factors. 22.6 It will be for the national health care systems concerned to manete eny mass-treetnent schene. This is an activity in which no "erternal"inter-country organisation can be a reliable substitute for netional services or systems. If, therefore, a suitable drug became available for use durin6the attack and consolidation periods in the Extension ereas, OCp involvenentin the actuel nass treetment would be somewhat limited. This obviously nesnsthat the services concerned must be capeble of achieving regular conplete coverate of the terget populations (frequency would be determined by thetreetment schedule) and that the teans involved must have the erpert knowledge required for proper diagnosis, sefe treatment and vigilant follow-up. 23 The ocf Lonq,Term Slraterv proposar : aveilabiritv of a reriable end convenient diagnostic test. 23.L During the attack end consolidation pheses the targets and ertent ofeerial lerviciding are based on entomologicel considerations and the diegnosis and foIlow-up of individuel cases play no particuler role in the conduct ofcontrol operations. The avallability of a reliable and sensitive diagnostictest would therefore have lts reel impact during the naintenance phese, erthough it could be of some use also for consoridation operations. 23.2 The importance of e diagnostic test thet met these criterie wouldlie in its use during the maintenance phese to detect ceses of the disease aten early stege, before rnicrofilariae (nrfs) can be detected by skin-snip nethods , s ince when skin-snips ere effective there ere enough mfs tocontribute meterielly to transrnission. The test would probably be given toall Per6on6 living in localities where experience has shown there to be acontinuing, risk of reinfestation or when unusuel concentrations of bleckfliesare reported. obviously the test might also be used es e tneans of follow-upin certein indicator populations. 23 .3 A reliab1e, sensitive and discriminatory diagnostic test wouldconstitute a step forwerd by making it possible to dete"i.ny resunption ofdisecse transmission that nright occur during the maintenance phase and thus totake corrective ection. Furtherrnore, if an effective drug becene eveilable,the test would have a major impect by diegnosing petients for treatment endthus contributing to the control of sporadic ceses of recrudescence. ocP/84.4 24 -28- The OCP Long-Tertn Stretegy proposal research end operational s tudi es 24.L The research priorities leid down in the OCP Long,-ferm Strategy are those listed by the Expert Advisory Conurittee (EAC) in 1982 i.e. lervicide development, drug development, and development of a rapid specific irununodiagnostic test for detection of early infection in the field. 24.2 In eddition, the EAC et its session in 1983 "considered thatpriority must also be given to a number of other critical research issues, all of which were of considereble importance in the development of the Long-rerm Strategy". These issues included : - the public heelth significanee of the forest form of onchocerciasis; - the impect of reinvasion on the success of the Progranrre in meeting its overall objective; - the determination of Ievels of prevalence and intensity of O.volvulus infections end essociated ABR end ATP levels below which trensmission is definitively interrupted and vector :"li:"l.illl?.i""ltii3"lilli"H.i: l:H:.greatlv scaled down; 24.3 The Strete6y propossl further suggests that research be continued on the significance of the forest blackfly species es vectors; on additional urethods of control (e.g,. edulticiding, bleckfly trapping and ground control); and on resettlenent patterns, the ecological effect of resettlement and socioeconomic development in resettled erees. 24.4 Finally, speciel ettention will be given to operational studies(research and developnent) on key fectors in the devolution Process. 25 The OCP Long-Term Strategv proposal: trainins 25.1 Since its inception the ProBramne has paid considerable sttention to training, either by granting fellowships for forrnal courses inside or outside the OCp aree, or through the acceptance of fellows wishing to familierize themselves with Prograrrne operetions. The subjects for training have so far been in the fields of entomology, vector control, hydrobiology, PeresitoloBy' ophthalmolo6,y, epidenriology and biostatistics, socioeconomic disciplines end other arees of direct interest to onchocerciasis control. The trainees have come nostly from the Participating Countries and from other countries in Africe with onchocerciasis problens' 25.Z frith the increesing emphesis on devolution and the important role which the prograflne cen be expected to pley in enhancing and reinforcing health care systems in the Participatlng Countries es part of overall socioeconomic and rural development, a broadening of the scope of OCP training will be ca1led for. On the whoIe, there will be an intensification of Ehe treining protrafine, which will continue to cater for subjects of direct relevance to Prograrnme operations, extended to such srees of particular interest for rural and overell socioeconomic developnrent as prinary health cere r manegement pL_.ry and as epplied to the environmentel f ield' to the adninistretion of renewable enerEy resources (e.t. solar enerBy end bio-energy) and to ag,ro-industry (forestry, enimal husbandry, soil protection, etc.). It is erpected that although OCP will play a catalytic and supportive role in such treining, close and active collaboration wiIl develop between the Sponsoring Agencies in this respect, each organizetion assuming responsibility for the aspect of socioeconomic developnrent which fells within its competence' -29- ocP/84 .4 25.3 the trainint ProBrarme to serve the Stretegy will be guided by threeprinciples. The trainees will be middle-grede and lower-grade technicians ready to work in the field, with some enrphasis elso on the treining of supervisory and nanogeriel personnel. By far the rnajority of the treinees will come fron the Ptrticipating Countries end the courses will as far aspossible be conducted in tlest Africa. Finelly, to fecilitate training within the Progranune area, apeciel efforts will be rnade to promote collaboration between the institutlons concerned end, whenever necessery, to strengthentheir educetional fecil.itles and capacity. 26 The OCP,.Lg4r,-ferq Streterv proposal : cost estinateg 26.L It is estlneted that uS$ 113.0 rnillion will be required for progremne operations during the third financiel phase (1986-1991) end uS$ 43.6 rnillionfor the fourth phese (1992-1997). The addition of research and training costsbrin6s total estinated expenditures to US$ 139.3 million and US$ 55.9 millionfor the third and fourth financial phases respectively. 26.2 The outstanding feeture of the proposed Lont-Tenn Strateg,y is thet all costs directly attributable to OCP come to an end after 1997, the end of the fourth financlal phese. Details are provided in the forlowing tebre: Fisure 1O Cost Estimate for Proposed Strately ( $000 ) 1 2 3 4 5 (3+4) 6 7 (5 + 6) Finenciel Phase Yeer Fixed cos ts Ver i eble costs Progranune cost for operat ions Research and training Total cost 86 87 88 89 90 91 12 814 15 564 t4 967 L2 873 11 558 8 880 099 E49 252 45E 25 2l 2l ?L 6 L25 6 t25 6 L25 2 625 2 625 2 6L5 18 974 2L 724 2L L27 18 833 17 518 14 840 60 60 60 60 60 60 61 61 61 59 59 59 III ( 1986-1991 ) 20 L43 17 465 Totel 36 360 26 250 139 26676 656 113 016 26 82 46 957 348 214 4 6 210 7 6 4 24 22 2L 19 L7 16 8 119 5 996 4 553 2 589 967 389 14 L293 94 95 96 97 5 441 4 122 4 003 3 284 2 565 1 848 59 93 27 61 95 25 11 10 92 6 526 5 667 4 116 2 7L2 1 988 IV ( 1992-1997 ) 74L Total 21 E63 2L 750 43 613 72 260 55 873 26.3 As regards Progrenune operations (excluding research end training) e comparison of estirnated expenditure for the second (USt 94.5 million) and third(Us$ 113.0 rnillion) financial phases reveals an increase of US$ 18.5 mi1lion. A similar comparison for the fourth phase shows e decreese of US$ 50.9 rni11ion. ocP/84.4 -30- 26.4 In submitting the Strategy to different assuruptions regarding the Ievel of funding for the third finencial phase (1986-199I), as required by the terms of reference (see Annex 1, peragraph 8), the following conclusions can be drewn. Supposing a level sinilar to that of the financiel provision for the second phase(1980-1985: uS$ 112.0 million) full control operations within the total ProErBm€ eree i.e. including that of the Southern and tJestern Ertensions, could be carried out (estimated cost: US$ 113.0 million), but funds would not be eveilable for reseerch (including the chemotherapy project) and training (estimated at US$ 26.3 nillion). 26.5 If the funding level for the third financial period erceeded that of the second perlod by 40a i.e. to US$ 156.8 rnillion, the proposed reseerch and training activities including what nay be required for the chemotherapy project during the years 1989 to 1991, could be readily acconmodeted. However, given the neture of Protrafine operations, the availability of eny surplus funds would not shorten the implementation of the Strategy. ?6.6 If, on the other hend, there were a reduction of the funding level in the third financiel phase as conpared with the second by 404 i.e.to US$ 67.2 nillion, control operations could not be undertaken in the lfestern Extension erea during the third finencial phase and the eventuel attainnent of the overall objective of the Protrslrme would be deleyed correspondingly. Any inplementation of the Stretegy below the proposed funding Ieve1 for the third finencial phase by delaying the phased irnplenentation of the tlestern Extension would prolong reinvasion in the western part of the present Protrarune aree end in the easterrunost zones of the Extension erea, end increase the risk of development of resistance to larvicldes, problens which would result in a steep rise in the total expenditures of the ProBrefine. 27. Translation of the Straterv into "plans of ection". 27.L The strategy to be evenbually edopted by the Joint Protremne Comrittee will provide a franework within which future OCP operations will be conducted and e firm basis for more detailed progranwring exercises. Obviously, a long-tero plan cannot Bo into future activities in sufficient detail to guide the ProBre^me management on all operationel matters of irunediate concern. It is therefore intended to trensform component perts of the OCP Strategy into distinct "pIans of action" (see also paragraph 3.3 above). This will be done es the need erises. 27 .2 The following is e list of subjects for which seperete plans of ection could usefully be prepared : - devolution; - operations in the Ertension areas; - research end operationel studies; - training,; - the menagement of chenotherepy. This list is in no way exheustive. ocPl84.4 Annex 1 Terms of Reference I DEFIT{ITION 1. As a basis for the future financing of the OCP it is necessery' as requested by JPC et its third session, that a long-term strategy be forrnulated which si11 detail the operetlonal pathweys to be followed to enable the "objective" of the Prograrme to be met rlthin a specified tinre-scele leadin6 ultirnately to the devolution of activities towerds the Perticipating Countrles. The responsibility for this task will rest with the Director, OCP. The terms of reference are es follows: (i) To refine the obJectives of the Progratmre in the light of current experience and results. (ii) To identify the optimal pathweys to bring the Protremne to e successful conclusion. ( 111) To prepere a strategy document identifyint the eostings appropriate to the verious options proposed, taking into cons iderat ion: - the results schieved accurnuleted since 1973 di sease ; by ocP includln6 the scientific results regarding the fIy, the perasite, end the - the technical erperience acquired fron about 10 years of spraying operations, monitoring and surveillance, and the advantages of the techniques used but also their linitations; - the finenciel constraints both of the Donor cormrunlty and the Pertic ipating Countries ; - the potential and linitations of chemotherepy, either through dru6s killing the macrofilariae, or sterilizin6 the females, sti11 to be developed and/or through existing drugs or a cornbinetion thereof, and the distribution of drugs; - the potential for tJest African countries concerned to become respons ible for maintaining echieved results successfully, individually accountlng for political, economical and social factors; - the determination of credible boundaries for the control areein view of the state of present erperience and the decisions to extend protection both southwerd and westward; - the manegerial and organizational structure of OCP, as hes existed so fer but also as needed in an operetion involvlng, in addition to insecticiding the core area of OCP, new neans end a much broeder area; - the original economic justification of OCp, echievements in thet reg,ard so far and potential achievements over the nert 10years and beyond, takin6 into account the econonic potentiel weighted reletive to the region. ocP/84.4 Annex I 2 II. PAR.A}IBTEBS 2. The audience will be composed of: Donors (current end potentiel); Participeting, Countries end those concerned by the lrestern ertensions; OCP itself, since the Plan of Operation for Phase III nust reflect the Long-Term Strategy; and the international scientific comnunity at large, because its role in support of OCP vis-i-vis governments end private foundations is of inportance. 3. The Long-Terrn Strategy will present to its audience e credible and acceptable Process by which the Programne will terrninete successfully. A credible process is one thet is technically sound and finencially feasible. Technical soundness requires that the Process has a reasonable chance of success in achieving objectlves. An accepteble process is one that neets najor preoccupetions of the audience. III. PROPOSED APPROACH 4. As a first step the objective of the Progranune needs to be redefined on the besis of the currently eveileble scientific and technical results and on reesonable assumptions regardint the time frame and resources es outlined ebove. They should be echieved throug,h a process in which the level of control activities cen be mainteined by the countries themselves, individually end collectively. The tiroe frame should be determined by technicel considerations and the need to maintein an efficient level of control, but should not exceed 12 years (two financial phases, starting with Phase III). Included in the same objective is the extension of the benefits of the current progrefirne to the countries that ere pert of the accepted extens ion. 5. The second step could identi fy the means available to reech the objective end esBess their intrinsic potentiel and lirnitations: a precondltion for this would be docurnentation and initiel review of bhe scientific and technical results gathered so far by the Programne in a manner that satisfies the internetional scientific conurunity. This is inportant beceuse continuous protress in understanding the digease and the vector hes strategic iruplications particulerly for the naintenance operat ioa . 6. A third step would be an exeninetion of criticel questions faced by OCP which the Long-Tern Strategy must eddress. These are: A l, scientific redefinition of the present Protraflne bounderies besed biologicel criterie. These criterie need to be developed based on: (i) vector differentiation and distribution, (ii) streins of parasites and resulting disease patterns, and (iii) type of terrain and infrastructure needs on B An evaluation of the scientifically esteblished boundaries in operetional feasibility. fhls irnplies a critical reevaluetion Southern llnits of the ocP erea and of the ltestern extensions. terms of of the cocP/84.4 Annex 1 3 The deterrnination of all tines: the number of larvicides which need to be availeble at (i) to sustain operations in the current OCp area, and ( i i ) to undertake extens ions end determine alternative vector conUrol methods . A critical assessment of the economy of the present operation, including: (i) Identification of fixed end variable costs. (ii) Opportunities for cost reduction: - by epplicatiion of modified epidemiological criteria - by changes in vector control schedules - devolution - other meens. ( i i i ) Determination of indicators/yardsticks enebling assessment of the economic efficiency of the operation. A criticel assessment Progranrme, particularly of the potential impact of chemotherapy on the (i) D E potential tine probability of frame for the developnent of macrofilaricides and success; (ii) review of the chemotherapy; potential operational problems of lerge scale (iii) vieble alternatives to long tern; macrofilaricides during Phase III end in the ( iv) development of indicators enabling measurement of protress in chemotherapy developnent. A critical assessment of the potentiel and linritetion of devolution in meintaining control of the disease, particularly with regard to the financial and institutionel absorptive capacity of the Perticipating Countries. Regerding modalities for devolution, cen maintenance of control in arees where devolution is feasible be underteken es projects by the national Bovernment, independently fronr but technicelly assisted by OCp? G. An assessment of the need for extension F (i) lrhat would happen to the current Progranme in terms of contror ofdisease if the proposed Southern end tJestern extensions were implenrented? the not ocP/84.4 Annex I -4- (ii) (iii) tJhat alternative control strategies can be considered? Is any of these a viable elternative to extending diseese in the proposed extension areas with the operation currently used by oCP? cen extens ion be undertaken at a rate concomitant with andproportion to the handing over of present OCP operations Participating Countries (see F above). control of the vector control in to ( iv) H A review and documentation of the socioeconomicparticularly with regerd to spontaneous resettlements impect of OCP to date 7. As a fourth step, the LonB-Terr Strategy could define two to three basic strategic scenerios, taking into accounb resolution of these issues identified earlier. Although these scenarios should be equally feasible, they would reflect different essunptions on the means, such es timing for chemotherapy, absorptive capacity of Participating Countries for taking over control operations, etc. Each scenario would be costed end staff inplications identified. Out of these possible scenerios, the Commitbee of Sponsoring Agencies (CSA) would agree on one thot would become the besic stretegy for Phese III. 8. In its next steps, the selected strategy could be subnritbed to three assumptions on the level of funding for the Phase IfI: (i) available funding of Phase IIf equel to that of Phase II; (ii) oveilable funding of Phese III 40a less then that of Phase II; (iii) available funding of Phase III 40a more than that of Phase II. For each level of funding, the inplications should be clearly spelled out: - on the final objective; - on the financing, of subsequent phases; - on the tinre frame needed to terrninate OCP successfully. Such activities as have to be eliminated from or can be edded to Phese III should be identified. OPER,ATIONAL CONSIDERATIOrlS 9. A preliminary document detailing the potential strategy or strategic options should be submitted for review no later then 31 ltarch 1984 and a final document ready for presentation to the JPC by 3O August 1984. 10. The Long-Term Stretegy would be elaborated under the authority of a project menager reporting directly to Director, OCP. The steff of OCP would be backed by long-tenn consultants. Short-tern consultants would be recruited to provide expertise on specific tasks. ocPt84.4 Annex 1 5 11. The CSA, being responsible for transmitting all documents to the JPC, will progressively review the Lon6-Term Strategy in its development. Prior to its submission to the JPC, this docunent will be submitted for consideration by the other statutory bodies of the Prograrune. It is thus suggested that, on the basis of the terms of reference, the OCP strategy team, in planning the exercise, establish review points. After each review point, it should also schedule a reesoneble time to incorporate revisions stenuning from the review. ocPt84.4 Annex 2 De1 imi tat ion of OCP Operet ionel Zones 1. In order to deterrnine the OCP Operational Zones (OOZ)1 and their respective boundaries within the current end projected ocp area, an entomological "profile" has been depicted on e map showing for each catchingpoint the highest ABR/ATP velues recorded during the three year period 1981-1983, and specified by Sinruliurn species wherever appropriate. 2. Using this nep as a basis, a srnall Eroup of senior oCP staff nenbers,thorou6hly faniliar with the operational and scientific aspects of the ProBrelrne, agreed on the characteristics end bounderies of a nurnber of OOZs which together make up the ocP operational and Extension ereas. The troupbesed its conclusions essentially on the entornological situetion, although sotne consideretion rres given to recent epidemiologicel trends and aeriel control operations. 3. A brief description of each OOZ, including the area covered, its cherecteristics and the neture of expected OCP operations under the Strategy is given belor: 3.1 002 01: the aree covers most of Upper Volta, the OCP sector of Niger, the eastern half of the part of llali included in the Progranmre and a "pocket" in North Benin; the total area of OOZ 01 is ZZ5 000 knrZ; kms river ever treated: 1 970; this OOZ is to all intents end purposes in the maintenance phase; there has been prectically no larviciding during the pest three yeers and OCP ectivities have been confined to enbonolo6ical surveillence, resulting in zero cetches or ABR/ATP values well below the accepted Ievels , ATPs in several cases being nought; el1 bleckflies identified belong to the Sinulium danrnosun/sirbanun cytospecies; neintenance activities should continue in O0Z 01 for several years to come, with a graduelly reduced entornological surveillance network; increasing emphesis will need to be given to selective surveillance of "risk spots", to rotetionel surveillence, to the rnobile teem approach end possibly to the use of treps; the epidenriological eveluetion efforts should be intensified in order to follow closely the morbidity trend in an eree where "incidence O" hes prevailed for e nurnber of years; this erea will also lend itself to operational research in the field of devolution and to the subsequent gradual transfer of OCP activities to the national authorities concerned. 3.2 W__OZI. the Zone coincides with the southern part of Upper Volta, a north-eestern portion of the Ivory Coast and e smell north-western stretch of Ghanien territory, in ell 60 OOOkn2; rivers: 990kms; 1 tui OOz is defined es a distinct, relatively uniforrn area and population within which onchocerciesis end its control has been following and can be erpected to follow the same pattern, chronologically and otheruise. 2ocP/84.4 Annex 2 until it is for two yeers 3.3 3.4 3.5 this OOZ is in the consolidation phase: in 1983 larvicidint wes confined to the wet and the beginning of the dry seeson using Temephos end alternete lervicides on the Bougouriba and Black Volte rivers; the Simulium damnosum/sirbenum, in sonre linrited association with S. soubrense is the prevalent vector in this eree with ABRs end ATPs well below the esteblished upper limits of tolerability; OOZ 02 will remein in the consolidation phase until the Uestern Extension becomes operational et which tine the Zone will move into the meintenance phase. 002 03: this area is nede up of the western part of the OCP covered zone of t{aIi plus the north-western corner of the Ivory Coast, making a totel of 72 OOO km2; rivers: 2 490 kn; 002 03 is subject to different types of invasion of Sinrulium dannosun/ sirbanum from breeding sites situated to the west end outside the current OCP area and, to a much lesser degree, of Simulium soubrense fron the south; the S. damnosun s.s. ABR/ATP values are ebove the upper limit of tolerence while the S. soubrense levels are well below this linit; this Zone will need to renain in the consolidation phase until the risk of invesion is discarded (tJestern Extension operational); at that point of time 002 03 will continue consolidetion for a further two years before being admitted into the naintenance phase. 002 04: covers the upper-middle part of western Ivory Coast as well as two srnall "pockets" elong the Lereba river inside Upper Volte, in all 79 OOO km2; rivers: 3 045 kn; this Zone is inveded by Simulium damnosunr/sirbanum from breeding places west of the present Progranune area and by Sinuliunr soubrense frorn the south and west; both cytospecies tend to eppear in nunbers ebove the eccepted ABR/ATP 1evels along the Sassendra river system as does S. damnosum s. str. in the remaining sectors of the area where on the other hand S. soubrense shows ABR/ATP values below those levels; resistance to organophosphorus larvicides has developed in the S. soubrense cytospecies thus necessitating treatnrent with B.t. H-14, and Chlorphoxinr on an intermittent basis; this eree is therefore somewhat heterogeneous in neture insofar as the invasion results in cons iderably higher catches to the west gradually decreasing towards the north-eest; OOZ 04 will continue in the consolidation phase "protected" against reinvasion (lJestern extension) and thereafter. 002 05: is made up of the south-wesLern and eastern parts Ivory Coast and of a small area within Ghana around Bui, i.e. krn2; rivers: 3 425 kn; of the 134 000 ocP / 84 .4 Annex 2 3.6 3.7 3.8 3 this Zone is characterized by Sinruliunr demnosun/sirbanum and Sinulium soubrense catches showing etps essentiaffy Uefoi 1OO1 (except on the Cono6 end Sassendra rivers where S. soubrense values exceed this lirnit); ABRS for both species are well above 1,000 except for the Sassandra river with S. damnosun/sirbenum values inferior to 1,000; due to S. soubrense resistance to organophosphorus larvicides, control of breeding sites is cerried out by B.t. H-14 only; control operations in OOZ 05 will follow the sane course as thet projected for Operational Zone 04. 002 06: is situated in the north-eastern corner of Benin covering an """" of 38 OOOkm2; rivers: 1 550 kro; the preveiling blackfly catches in OOZ 06 ere of Simulium damnosum sirbanum with fairly high ABRs and some ATPs below 100; the aerial control, for the last one or two years confined to the wet seeson, is carried out by the use of Tenephos only; the area is probably inveded from the east and elmost certainly from the south-west; OOz 06 will remein in the consolidetion phase until the Southern Ertension becomes operational end two yeers thereafter before moving into naintenance. OOZ Olt cuts across the north-western part of Benin, the north of ToBo end the territory in Ghana lying eest of the upper seBment of Leke Volte; the area covers Z1 000 krn2; rivers: 2 395 kn; the Zone is characterized by Simuliun demnosun/sirbanun in the north and groups of poorly distinguisheble bleckflies in the south; only a few of the catches heve led to the identificetion of ABR/ATPs above the levels recognized as intolerable; continuing invasion - in which S. squarnosurn is also involved - takes place from the south; aeriel treatment with Temephos only which previously went fer into the dry season, has for some years been confined to the wet season; OOZ 07 will continue in the consolidation phase until full oCP control operations start in the Southern Extension area after which the Zone wiIl remain in consolidation for two years before proceeding to the maintenence phase. 002 08: is made up of the northern thirds of Ghana and Togo with two minor extensions into the north-western part of Benin, and Upper Volta around the Red Volta river; the total surface cones to 85 OOO km2; rivers: 2 810 kn; the predominant blackfly species in this zone is Simuliunr demnosum/s irbanum rnixed in the eastern part of the area with a srnal1 number of Simulium soubrense; although some locaI breeding occurred a couple of yeers ago, resulting in fairly high ABR/ATPs at e number of cetching points, aerial larviciding with Temephos during the last three wet seasons seems to have brought the situetion under control; 1 as was the cese also on the lower Bendema in 1983. 3.9 3 .10 ocP/84.4 Annex 2 4 the current Lreatnent schedule (Temephos during the wet seeson only) will continue for another yeer, following which the Operetional Zone, now in consolidation is likely to move into the naintenance phase. O0Z 09: coincides with the Southern Extension aree, and is currentlyin the preparatory phase. Assuming that two additionel larvicideg become available within the nert year, ful1 control operations could start in that aree eerly in 1986. The attack phase would last for three years and the consolidation phase another two years after which 002 09 would move into the maintenance phase. (Area: 111 000 htr, rivers: 5 830 km). 002 10: is in the exploratory phese. Control operetions once epproved by JPC could start under the sane conditions as those mentioned under 3.9 above (satisfactory larvicide situation) and would heve the sarne beneficial effect on neighbouring oozs ( inparticular cohorts 02, 03 and 04) es that referred to in thepreceding paragreph. Arthough a certein emount of inforrnation anddeta hes alreedy been collected in the Seneganbia area, a continuedintensified deta collection and analysis over the next two years would be another prerequisite for the beginning of control operations. (Area: 440 000 km, rivers: 22 O0O km). ocP / 84 .4 Annex 3 Control or no Control of Forest Species of Bleckflies 1 Background 1.1 The original plen for Programne operations, as recomrnended by the Preparatory Assistance llission to the Perticipating Countries (PAG), linited vector control to the savanna zones in the Volta River Besin Aree. Thus, by iruplication OCP ectivities were directed essentially towards the control of the sevanna species of the bIackfly, principally S.sirbanun. S imul i unr sum s. s L.2 Shortly after Prograrnme operetions vrere launched, fairly rnassive invasions of infected blackflies into the mid-western part of the OCP area were reported. Conconmitantly Participating Governnents expressed the desire to have the operations extended to control onchocerciasis in the area south of the then idenbified southern boundary, from where the major parL of the invasion originated. This led in L978/1979 to the extension of Progrenuue activities to Southern Ivory Coast which involved controlling all vectors in that aree including the predominant forest species ( S. soubrense/ S. sanctipauli ) . This seemed possible as the forest species were equally susceptible with the sevanna species to the larvicide in use. 1.3 However during the following two years resistance to tenrephos appeered anong S. soubrense/S. sanctipauli lervae to the extenb thet replacement lervicides (chlorphoxim, !!.H-14) had to be enployed in the Ivory Coast. This resulted in a sharp increase in operationel costs ln the area concerned especially due to the greater quentities of B.t.H-14 that had to be applied and the need to enteBe a larger and more exPensive helicopter. 1.4. tJithin the OCP aree es its exists, two fairly distinct forms of onchocerciasis are found. One is the "savanna" type with rather debilitating manifestations, including serious eye lesions often leading to blindness. The other the "forest" form, is considerably nrilder in its effect, rarely results in serious eye complications and never causes significant socio-economic problems. Recent findings seem to indicate that the two forrns are ceused by two different strains of onchocerca volvu1us. 1.5 The close association of the presence of S.damnosum/S.sirbenun and the ',savenna,, fornr of onchocerciasis hes led to the conclusion that this forn of the diseese is predorninantly transmitted by the S.dannosum s.s. and S.sirbanum species. The two species prevail in the savenna area but are also found in certain foci in the forest zones during the dry seeson. 1.6 Another species S.squenosum is considered to be a vector of secondery inrportance in iJest Africe. Although it can be found both in savenna end forest zones it appeers under rather specific ecologicel conditions, it is easily controlled, and its propensity for reinvasion is restricted. L.? S.soubrense/S.senctipauli are the predominant forest species within the present erotrafine erea and in the Southern and tJestern Extension erea. S.soubrense is cepable of migrating from its nornal forest habibat to the sevanne zones as fer north es 1Oo latitude, particulerly during the rainy seeson, and of settling there temporarily, occasionally during more than one season, ocP/84.4 Annex 3 ? 1.8 The forest speciea of the vector heve been found under experimental conditions to be eble to transmit onchocercus vo from patients fron both forest end savanne, zones cerrying the respective strains of Onchocerciasis. However, there is sone doubt es to whether these species in natural conditions have the seme capBcity to transrnit the savanna strain outside the forest aree 8s they heve to transmit the forest strein in the forest aree, their naturel hebitat. This will only be clarified when suitable methods for identifying both streins have been developed. Surveys have shown that the severe savanna form of onchocerclosis ir not found in the S.sirbanun. ebsence of S.dannosum s.s./ 2 The case for the discontinuation of control of the forest vector 2.L For the Progranmre to succeed in eliminating onchocerciasis es e disease of public health importance throu6hout the OCP area priority must be given to the control of the vectors which are known to transmit the most serious end debilitating fornr of the disease. At this stage of our knowledge these are the savanna species S . damno sum s. s. and S.sirbenun 2.2 An inportant fector in determining the extent to which the Prograrnne wilI succeed in reaching, its objective is the reinvasion of savenne species fron the south and from the west. It has long been recognized thet without control eined at these species in Southern Ivory Coest and the inplementation of full OCP operetions in the Southern and lJestern Extension ereas, the Protramle will be erposed to continous reinvasion. The irnplenrentation of Extension operetions is therefore of capital importance. However es long as a comparatively high proportion of Prograrme operations and OCP funds were to be directed to the concomnitant control of forest species resistant to temephos in the south-western pert of the present Progranure eree, there could be no shift in resources from this area to susidize the cost of the Extension operetions. 2.3 Another factor connected with the control of forest species is that thii control can never be cornpletely effective with the means available at the present tinre and would have to continue indefinitely. This has been cleerly denonstrated during the past four to five years when migration northwards of forest species from the abundent and pennanent sources in the south towards the north has occurred regularly each year. Also, elcept in 1983, the costly control of S. soubrense/ .sanctipauli has been of doubtful value in prevent i ng this mi6ration of infective vectors and in interrupting the transmission of the ,'forest" form of onchocerciesis wherever L soubrense/S. sanctipauli continued to be found. 2.4 The above considerations would obviously also epply in the Southern and tJestern Extension ereas if the Programne had to control S.s rense. This would also entail thet the Protremne boundary in the west would need to be extended practicelly to the Atlant ic oceen into an eree where control activities would not only be exceptionally difficult, but also exceedingly costly, 2.5 Horeover, the control of S. soubrense/S. sanctipeuli , requiring lervicidint to continue for en indeterrninate period, could give rise to serious resistance and environmentel problems. ocP / 84 .4 Annex 3 3 3. Conclusions 3.1 Considering that transnission of the "sevanna" form of onchocerciesis has been confirned as being closely associated gith the sevanna species of the vector S.demnosum s.s. and S.sirbanum; that the role of the forest species of the blackfly in the transmission of the sevanna form of onchocerciesis is at present unproved; that the "forest" form of onchocerciasis transnritted by S.soubrense/S.sanctipeuli is comparetively mild; thet the cost of continuing the control of forest species is inordinately high and would constitute an inpediment to the early implementation of full operations in the Extension erees; that the ongoing control efforts against the forest species are not very effective with the tools currently aveilable; that control of the forest species would have to continue possibly indefinitely risking further resistance and ecological disturbance, it is proposed that S.soubrense/S.sanctipauli control be discontinued for the time being within the present (1984) ProBrerune area and not included in the Long Term Strategy. 3.2 Lirniting Progremne operations to the control of the sevanna species, curteiling reinvasion by extending operations, and controlling the severe sevenna fornr of onchocerciasis in the extension ereas, would aIlow for bhe ultirnate attainment of the Progremne objective. Resistence being confined essentially to the forest species would no more be an inunediate operational problen. 3.3 At its fifth session in 1984, the Expert Advisory Conmrittee (EAC) carefully reviewed the situation and peragraphs 45 and 46 of its report steted : "In the light of evidence evailable EAC reconunended the temporary cessationofcontro1specifica11yeimedattheforestvector,!-@,in southern Ivory Coast especially as this was not a vector of proven importance in the trensmission of sevenna onchocerciasis, The control of savanna vectors in the forest areas should nevertheless continue in order to prevent reinvasion. Reseerch both on the epidemiology of forest onchocerciesis end on the relationship between forest vectors and the transnrission of savanne onchocerciasis should be intensified. The Conunittee proposed that the situation should egain be reviewed two yeers hence. However, this should in no Hay prejudice the inrplenrentation of the Lont-Term Strategy." ocP/84.4 Anner 4 Selection of the Lonr-Tern Stratetv Proposal frorn among the five Optiong 1. The process of selecting the proposed Stretegy hes been one of gradual elirnination of the unsuitable options emong the five considered. In the cese of el1 five it can be foreseen that the major part of the originel ProBrslrue erea would complete ten years' maintenance et some time between 1991 and 1994. The differences in the operatlonal inpllcations of inplenenting the various options ere therefore mainly centred on the Operational Zones sltueted to the east and west of the present OCP aree, which ere exposed to reinvasion from sources outside the Progratmle Area. 2. Under Option 1 the Progreflme would not be able to reech its overall objective owing to reinvasion end continuing transmission in the zones bordering on the two Extension areas. Consequently consolidation operations would heve to be continued for nEny years to come, if not indefinitely, and the devolution process in the two border ereas (002s 02, 03, 04, 06 and 07) could only be put into effect on a limited scaIe. Also resettlenent and socioecononric developrnent would be seriously hanpered in the arees in question and the continued larviciding needed could heve serlous edverse effects on the environnent. Although Protrermte costs would be at a fairly Iow level in view of the linrited operatlons involved, they would continue to be incurred for a considerable time, if not indefinitely. For these reesons, Option 1 wes elinrinated as a feesible besis for formulatint e LonB-Term Stretegy. 3. The above considerations also epply to Option 2, under which control of forest species would be discontinued, with a corresponding reduction in the cost of operations. otherwise there would be no difference between the irnplications of implementing the two options and Option 2 wes consequently rejected as a basis for Strategy developnent. 4. option 3 would result in stopping reinvasion of the eastern Zones of the present OCP aree by infective bleckflies fron the south and protect the populations of the Southern Extension eree against trensrnission of onchocerciasis. This would eventually enable the devolution process to be fully irnplemented in the enlerged Pro6ramne area (OOZs 06, 07 and 09) end oPen it up for resettlement and socioeconomic developnent. However, the decision not to extend control operations into the lrestern Extenslon aree would nake it necessery to continue consolidation ectivities indefinitely in the lrestern Zones of the oCP eree (OOZs 02,03 end 04), thus preventing devolution and impeding resettlernent and socioeconomic development. The 1eve1 of operetional costs (which would obviously exceed that of implenenting Options I and 2\ would first drop when attack and consolidetion operetions in the Southern Extension eree were completed, and then continue et the sane level for an indefinite period. ocPt84.4 Anner 4 2 Because it would meke it irnpossible to put ectivities in the western pert of the progrenme area, impede the processes of devolution, resettlernent and and was therefore not considered viable. an end to consolidetion Option 3 would therefore socioecononic development 5. The consequences of irnplementing option 4 would be very sinrilar to those of implementing Option 3, with the difference that Option 4 would protect the western Operational Zones (OOZs 02,03 and 04) against reinvasion instead of those situated in the eastern part of the OCp area. Option 4 was therefore eliminated on the same trounds as those steted inparagraph 4 ebove. 6. Option 5 is the only operational approach thet would allow the Programne to reach its overall objective within an acceptable period of tirne and at a reasoneble cost. It satisfies all the key criteria, such es preventing reinfestation, allowing for complete devolution and permitting early resettlement with associated socioeconomic develgpnent. The proposed operetions are technically feesible and the entry of the entire OCP area into the meintenance phese before the end of the twenty-year period originally foreseen for the ProBramle would preclude the risk of serious environmental dema6e from continued larvicide applications. Furthermore, although additlonal costs would be involved durin6 the first few yeers of operations in the Extension areas, they would be rapidly offset by the cessetion of control activities in the present OCP eree. lloreover, OCP operations es such would cease entirely once the lest operational Zone hed been in the maintenance phase for five yeers, that is by 1997. Consequently, the assunptlons and operationel approach inherent option 5 have been selected es the besis for the propoeed Long-Term Strategy. 1n ocP/84.4 Anner 5 Onchocerciasis Control in the lJestern Ertension Area A brief Descripti of the Approech 1 Introductlon en4 beckrround 1.1 tJhen proposrls for an autonomous Senegernbie Onchocerciasis Controlproject were reviewed by the Joint Protreflme Comnittee et its second session in Decenber 1981, lt was ecknowledged thet, for both health end socioecononlc reesons, there was emple justiflcation for carrying out control measures. It was also eg,reed that any such control meesures to the west of the Progrenme area should be inrplemented within the franrework of an OCP extension and not es part of e separate multi-disease control project' L.2 Accordingly, the Comrittee asked OCP to reeppraise the Seneg,anbia Reasibility Report, to collect additional information frorn the sub-region' and to prepare a revised plen of operations for an OCP tJestern Extension. These directives were inrplenented throughout 1982, and when the JPC met in Decernber 1982 it was presented with a revised plan of operations entitled "Proposels for e lfestern Extension of the Progrenune in llali, Guinee, Guinea-Bissau, Senegel and Sierra Leone, (Document OCP/82.3). this document wes sig,nificant in two respects. 1.3 Firstly, it introduced the concept of shered technical responsibilities between the Prograrme end participating Sovernnents, involving the utmost possible utilization of netionel menPower end rnateriel resources. OCP would heve overell responsibility for direction and nenegenent, would conduct all eerial vector control operations, and would supervise and essist (where necessary) with epidemiological, entomological end envirorunentel evaluation activities. fhe nrajor contributions of netional euthorities would be the nenpower required for the verious evaluetion operations and for 1o6,istic support. This concept still constitutes the cot[non denoninetor of all plans for exploratory, preparetory and operatlonal ectivities in the tJestern Extension eree. 1.4 Secondly, the report went e 1ong, wey towards presenting a realistic perspective of a greetly expanded OCP. The proposed southern boundery of the irestern Extension eree was drawn strictly in terms of the known distribution of savenna vector species. At the same tinre some of the difficulties to be anticipeted in implenenting a llestern Extension control operation were listed. Lines of conununicetion were considered to be inadequate in meny parts of the Extension area. Combinations of rugged terrain, dense vegetation and adverse climete, especially along the southern border of the Extension area, were expected to conrplicabe, if not delay, vector control operations end the logistic support facilities upon which their success depended' ocPl84.4 Annext _r_ 1.5 rt was thus obvious fron the 1982 proposal thet a number of "rptoratory studies would be needed in the uestern Extension area before ocP would be in a position to launch control activities on the basis of e carefully designed and realistic stratety. tJith this in mind, the Progranoe presented e second PePer on the lJestern Extension to the Joint Progranne conmittee at its third session, outrining the erploratory activities that would need to be carried out in the eres at the earliest opportunity' However, for a variety of reasons ocP Hss not able to launch the proposed activities during 1983, although ettention was given to some of then (rnainly entomological and hydrological) by the Inter-Country Project ICP/PDP/Q03 (with headquarters in iematol, using funds nade aveilable by the UHO Regional Director for Africa. 1.6 At its fourth session (Paris, December 1983) the JPC approved the OCPplan of Action and Budget for 1984, which included a budgetary allocation of US$ 1.28 million for exploratory activities in the iJestern Extension area during, 1.984. A sumary of the nore inportant findinBs to date is given below' Z. Exploratorv activities in the proposed testern Extension area end the 6iEiEional iisnificance of the findinrs 2.L For the sake of brevity, it is proposed not to review the results all the activities, but rether to highlight the nrost significant findings relevance to the overall concept of operations in the tJestern Extension eree' of of 2.2 Collection of technicel inforrnetion in the lJestern Extension connected studies area and 2.2.L Through close and friendly collaboretion between the steff of the nationel onchocerciasis teems concerned, of the ICP/PDP/OO3 project, and of the Onchocerciasis Control Programre, valuable technical end operetionel information is being collected from those parts of the testern Extension area thet will figure pr-orninently in the first attack operations' This applies in particular to aetermining Sinrulium species distribution, in order, !-nte.ra.I!, to define nore precir"fy tt" fi.itr above which blackflies constitute a risk of transmission, the Uiiing hebits of the vector, the seasonal chenges in and density of vector populations, the location of vector breeding sites ' the selection of capture points, end the leve1s of susceptibility of 1erva1 populations to various larvicides. Studies are elso under Hay or planned on such rnatters as the significance of the vectors implicated in the trensmission of ,,sevenna,, and "forest,. onchocerciasis, the productivity of breeding sites in relation to water leve1s, the equetic environment and the logistics of aerial treatment oPerations. 2.3. Contributions of participating governments end national services 2.3.L All the governments of the Perticipating countries accept that strong national participation is en integral pert of the Hestern Extension concept end have reconfirmed their reediness to invest nationel resources to the best of their ebiIitY. 2.3.2 During 1984 there were very positive responses to OCP requests for the provis ion oi staff, the nomination of candidates for traininB and the slmplification of adnrinistretive procedures (inunigration, customs, over-fliBht authorizations for eircraft, etc.). Hydrologicel services in ltali and Guinea ere now actively engaged in upgrading hydrologicel networks to meet ocP specifications. ocPl84.4 Anne: 5 -3- 2.4 Fectors releted to hunan 6eography 2.4.L For a g,reat nrny reesons, ls is elso neinly the case in the presenL(1984) Prograrme area, ell the naJor centres of governnent, ednlnistration' cotrnerce and trade, in the frestefn Ertenslon Participeting Stetes and all the rnain ereas of hlgh hurnen populetion density are in coastal and other peripheral erea3. Furthermore, beceuse of the 6reat distances involved, it is sefdon feasible to maintain roeda 1n ercellent condition' 2.4.2 The obvious inplications of this situation ere that OCP tuust anticlpete conducting, eerial optretions fron a Lirnited nunber of carefully selected beses, "nd carrylng out survelllence activlties on e nore linrlted scale than is done in the existing ocP aree. 2,4,3 The hinterland of the l{estern Extension eree (especially Guinea' but elso parts of western l{ali end eestern Seneg,al) contains rich natural resources and en increasing nutnber of internationel investors are conducting fees ibillty and pre-investnent surveys of potential rnining, ereas end of extensions to existlng roed end reilway networks. As a result, the network of lines of conurunicatlon is erpected to expend. At the sane time it mey very well be that onchocerclasis control would be a condition gl-ge--9.@ for sone of these planned proJects to become feerlble. 2.4.4 However, ntny perts of the lJestern Ertension aree wl11 renain poorly supplied with roade.- For such arees ocP has been experinenting with elternctive ways of conducting sone of its operetions which nornally depend on rerdy access to river benkg. lltrenever posslble and necessary' the entornologicel survelllence will be besed on cheap end well-adapted vehicles thet nrke it easy to reech valleys thet cannot be reedily reached by conventional meang of transport. 2.5 Factors related to neturrl 6eography and climate 2.5.1 In sone limited pertr of the tJestern Ertenslon erea various combinetions of high ground, rteep-sided velIeys, dense riverine veBetation and 1ow cloud preBent very chellen6ing conditions for eerial larviciding and surveying operetionr, conditionr which ere not g,enerally encountered in the exlsting OCP area. Studies are continuing wlth a view to developing ways and means of using effective vector control technlques adapted to these speclal sltuations. 2.5.2 It is fully realised thet vector control and surveillence operations in the Uestern Extension area cre unlikely to be replicas of those in the existing OCP sree and will nev€r be quite so streightforward. However, the core of OCP sclentists and techniciens concerned with vector control operations are confident t,hat effective control of onchocerciasis over the whole of the proposed lrest€rn Eltension area is feesible within the proposed time linits. 3. Basic conslderationg for the tJestern Extension atteck phase 3.1 The boundaries of the tJestern Extension Bree, es illustrated in the main text of the Lont-Tenn Strategy proposal, have been delinited on the basis of the distribution of savfnne species of the Slnulium dernnosurn species compler. ocP/84.4 Anner 5 -4- 3.2 l{embers of the S. soubrense/ sanctipauli species pair have been detected in the headweter tributaries of the river Niger in Guinea. ItIo speciel measures will be taken to control such populations, unless future research indicates a need to reconsider the situetion. 3.3 Vector control operations will cortrnence in the east of the Uestern Extension area and be gradually extended in a westerly direction from the present western boundary of the OCP area in accordence with the indications g,iven in the nein text of the Lont-Terr Strategy docunent. Operatlons will stert in the easterrunost part of the aree. A yeer leter they will be extended throug,hout the middle part and in the third yeer into the remeining westerly pert, thus bringing the whole of the uestern Ertension area under control. 3.4 OCP will have overall responsibility for the direction and manegement of the execution of the prograrune in the lJestern Ertension aree, and dlrect responsibility for vector control operations. 3.5 There ui11 be strong national particlpetion in the collection of evaluation data, as ls already the cese in respect of the current exploratory activities. Analysis of such data will be conducted jointly by the nationel authorities end OCP. National authorlties will also provide the bas ic facilities end services required for establishing bhe necessary operational infrastructures. ocPf 84.4 Annex 6 OCP O onal Zones and Correspo nding Operational Phases Explorarory (ZOP tO.1) Prtgararory (OOZ 09) Arrack Contotrd.rron IZOP OZ,03, 04, 05,06.07, OBI Mernrcn:nce (OOZ Ol ) o I ,----__p-________ ____ __ _i t I F I\rI SITUATION IN 1984 0r I M I I 't0.1 \l I I L 7 '{ e -..\. ( (-, r\) r o4 .:Q @ t-b \ .\ !t ( I ( E P A C M o '.r (j ocPf 84.4 Annex 6 OCP Operational Zones and Correspondi ng Operational Phases E P A c M o * ----p-- ,, ----------_ ___l t I h SITUATION IN 1984< , /)> M@ I C ,J r:tr o7( ,/ @ c \...1 l- @:jc( lr t -( I a Explor.tory (ZOP 10.1) Prcp5ratory (OOZ 09) Attack Consolrdation (ZOP 02,03,04, 05,06,07, 08) Meintenancc (OOZ Ot ) i ( t\ @ tl