Vector control unit report of activities for the month of the July 1975

*-*ia Orgenlsetton noAdla].e de la Sant6p-ogpnme tle lutte oorrtrs J,r0rchooes$coE€ B.P.54g 0uagadougou Haute-Vo1ta TECTOR CO}ITROI UNIT RNPO FoB TI{E LIo}ITH 0F JIIL ocP/vcu j .[ 'j - D.A.T. Ba1d.ry(acting Unit Chlef) t' During the nonth of July; flve cyeles of aeri.al Larrricictlng operati.one were successfully executed; soEre sole1y by hellcopters, others by u mixetl hellcopter/flxeti-wing f1eet. Nev6rtle-1cge, ].=ge .uunbers ofSlPElf%A?qpP"lr* f1Ies, most of theri parous ancl some of tben rnrg6tsil, contlnued to be founrd. la seteraL parts of the ?hase I zone. fr1 end,oavourlngto cletertine the causes of this nost d.isheartentng si-i;uation, iatensive and' very conmendable efforts have been matle by the staff of the VCT ar.d, ofDvergreen Heli.col-rters Inc. Despite tlrese efforts, fly numbers continued tobe high at the end of the month, and although a conplLte explanation for thesituation has not yet been found it is now certain tha'b we have pinpointectat least qose of the contributing factors. These have been discussedpart1v in-6EE writerrs report on Aerlar operatl;;"-(;;;;; ;;;ri"i-I"apartly in the report of the Dntonologist in charge of Entomologicai Evalu-ationsi they are further discussed belovr. The month has also witnessed considerable progress in upgrading thelnfrastmcture of ?hase f operations, in the collection of pre-treatment entomoLogtcal tlata for Shase II operations, antl in preparations for varledactivlties in the Phase II ancl IIf zones. ]-. ANRIAI, OPERATIONS TI{E }}IASE I ZOItrE (8he rvriterts own report on Aerial Operations, annexed, hereto, refers.) lhe numbers IabLe 1. of aircraft flight hours for the month are presentett in t b1 1.1 IARVICIDTNG O}EU.TI OI{S Is rainfall lncreased over the ?hase I zone 1t becane necessary totreat a greater number of watercoursea, and in many cases, to apprlclabl-yi-ncrease lnsecticirle dosages ln order {o keep pace with heighteningdlscharge rates on nany of the larger rivers. One very vreloome eonsolationfor these extend.ing operatlons, t?as tha-t on many rivers 1t was possible F I a 2- to greatS-y increase tlre distanees between treatment points, wlth consequent savi.ngs in flying tine, tvear and. tear of euircraft, etc. In ord,er to cope with lanricid.ing operations on the J-a.rger rivers, theHeIl-Porter equipped with a nevrly d.eve3-oped ilapitl Release slstel (nnS) vras put into operetlon. The work-load of tliis aircraft lvas progressivelylncreased. through the last three Larvlcid.ing cycles of the monilr, InAugust it will treat all those watercourses previously sched.uled assuitable for fixed-vring opera.tions - nltldle and lorzer SLaclc Vo1ta, nid6.Ie and lower Comoe and nidd.le and lovrer Band.arru. Hellcopters contlnued to treat the upper reaches and trlbutaries ofthe larger riYers, extencling their circuits, as and when necessary, totreat rlvers that hatl not previously required treatment. In a6ttition, and as it became progressively more tliffieuLt to treat the headwaters of !!:e Sanifing (Sihasso region)-by han,I1 thi' responsibillty for treatingthe tributaries concerned was trensferred. to a helioopter. Although the senior staff of the VCU are stil-l roystifiecl by the sustainect high densities of S._dqq4osun females in several parts of thetreatmentzone(particu1ar3.y-ffia1Bouanamx.aai;_i";;;u)ir'"i"-iu no tloubt that for at Least ninety-nine per cent of the time aerial treat- ments have been made in the correct (or what is assuraect to be the correct)maruler' It is certainly out of the question that the occastonal badlytreated' breeding site could account for the numerous fLies encountered inthese areaso L.2 OT}MR AI]BIAI O?I]RA TTO]IS , X.lthough severaL theories have been put for.ward. in an attenpt todetermine the origins of the nany flies found in some plaees, lt was forquite a whl1e consldered 1tkeIy that breeding had been contj.nulng ln somebreecling sites that hacl either not been properl;,, treated or had ienaineitundetected. To facilitate clarlflcatlon of thls, one helicopter (wo. w79e9,r) was usedl almost fuI1-tine to transport personnel of the evalultlon network(particularl-y Dr l/a1sh ancl I.Ir Hendlricd)-;; inaccessibLe stretches ofrlver and to position them on the grounC. as close as possible to potentialbreetling sj-tes. For these activities the he3-lcopter ilew 84.? hours, but even this was not enough to cope witir the number of very intensive breetting t-.-t" 9l9cks required. For this reason, the fourth stanh-by hellcopter(l[o. 59oo7) was brought lnto operatj-on on ]-4 Ju1y. By the end of the monthlt hadl flown six nj.ssions and ]2.0 hours, bringing trrL total flight hoursfor surveys up to l-16.7 hoursi 47.4 hours nore t[on during June. L.' IN;}]CTICTDE Thelitres; TabIe_ 2. quantlty of insecticltle clispensed during the month was 829r.6 3295.0 lltres more than d.uring June. Detair-s are glven 1n , I -7- On 23 JuIy, 91100 litrcs of insecticide were received, by air freisht shlpment" Ifiost of this has now been distributed.. T]re smalf- (Zl-fftre)drums that this and the previous batch vrere received in are not appreciotert.Fewer dr'.ms can be serfeLy transported by lorry (conpared to the 55-1itre clnrms) and alrcraft retiiling tine is extended. ft is 'bherefore veryinportant tha"t future batehes of insecticicle are despatched in 55-Iiire d.:rums. 2. ENTOIIIOIOGICAI EVAIUI TIONS I}T T}TE PITASE I ZONE (Dr ,lalshr s refers. ) report on Entoraologi-ca1 i.)valuation, annexed. hereto, The performance of the Entomological Evalu:Ltion Network was reasonably satisfactoryr although it is annoying tha.t the effj-ciency of g631s m.t.s3g- scopists in ttistinguishing betvreen p3.rous and. nulllparous f}ies, 1s below stand.ard.. During the nonth tremendous efforts were mad.e to check as many rlversas posslbler in order to detect posslbly breerling sites. Dr iialsh andI,[r-Henderiekx, using hel-icopters to fuII advantage, checlled painstalringly and in great d.etail an impressive number of sites. At the sane ti.me,I'ir 0u6drao8o, by nautical neans, examined. many of the Blerck yolta I sinaccessible and d.ifficult rapitts. However, d.espite these efforts, anincreasing nuuber of possible breedrng sj-tes on. ti:e larger r1vers (".g,Grechan on the ],eraba, ?1eye on the 3laek Yolta) rlefled a1l- attenpts to eheck them; some are inaccessible by ground, air or water and others aretoo dangerous to try and. reach by swirming. In the I(orhogo and Sikasso Sub-Sectors, reductlons ln the numbers of catching points for f1ies, ratj-ona,l-ised evalu:'.tlon proeed.ures, but at the saxce time and over a wider area, it was necessary to introduce new eatchlngpoints to monitor events on many tributary streans that had. recently coruoenced. to fIow. 2.L BREEDING SITE C}MCKS 2.1.1 CIIIICI{I}TG OF tilE.^-TDD BREEDING SITES Although breeding si.te checks were routinely nad.e of alL accessible water-eourBeg, the main emphasis was on those larger rivers where large numbers of flies v'rere caught, i.e. Band.amal Bou, leraba and Black Vo1ia. In all y.4ol breedlng site checks were made during the month; in 29 ceses 17.2771 evid.euce of current or recent breeding vras discovered. So:ae of these breaks in control v,iere und-oubtedly due to an lnaclequateperfo:moance of the insecticide, whl1e others can be attributecl to unusualhyttrologtcal conditions that make sr-lccessful treatment almost unattainable.Hovrever, lrrespeetive of the eauses of these breaks ln control, they cou1d, not on their ovrn account for the sustainecl. high fly tlensities found ln some valleys. ./. -4 ?laces where larval populations $/ere found. and gave most cause for concern were: - on the lower Banl.flng - on the Blaek vol-ta in the Dedougou area andl at several points south of the Boromo bridge - at tvro points on the Bougouriba on the lower leraba in the reglon of the road britlge (lont Routier) - at several points gn the Band,ama and, its maln tributary, the Bou. AlL these plaees eontinue to be kept und.er elose su:rreillance, but in several cases ehecks vrl1I have to be discontl.nuetl as the sites beeomeprogressively more diffieuLt and dangerous to enter. This is very unfortunate,but an unavoi-d.abIe hand,j-eap that has to be aecepted.. 2.I.2 SEARCI{ES FOR NEi/ SNXEDING SITES As many tributary streams eomnenced flowing, so it became necessaryto concluct aerj-al surveys to detect possible nevr breeding sites. As a result of these surveys several smaII, but nonetheless J-nportant, breedlng sites were found, (and have subsequently been treated) in ttre Blaek Voltal Comoe and Banda^ma va1Ieys. 2.2 CA?TUIID AliD DISSECT ION OF S. DAIlItlOSUIi[ FEIU.IES The number of ca'tching points was reduced. from L29 (ttre.lune number)to L27. In contra.st, the nurnber of catchin[J days was signlficantlyincreased frori 455 (in June) to >45. unforiunately, this very conmendable effort was rev/ardect with disturbingly high catches, and infectlon rates in some regiono. The numbers of flies captured at a representative nunber of places inthe rrrain river valleys are shov'J"n on the eight graphs attached hereto, Some observatlons on each of -bhen are mad.e belovr: lower 31ack \roIta Val1ey At all the eatching points along the lower Blacl; Yolta (nui, Chache,[agadi) tirere vrere appreciable increases in the nr::nbers of fiies caught, especially during the periorJ. Zl-24 Ju1y. Similar increases were also noted further north along the middle reaches of the Blacir Volta, along the Bougourlba. and in the Dedougou area.fn the l-atter arear loca1 unsuccessfully treatecl breeding sites were held responsible. I -5- Upirer Black Vo1 ta Valley (s"nandeni ) The numbers of fLies caught in this area have renained extrenely Iow, and a very satisfactory 1evel of control is clained. [ransmission hlo certainly been interrupted for several weeks. Thg sggirrg-Ja11eX (lanpe.sso ) The hlgh f]-y nurobers recoJrded on the Banifing are attrlburted to a series of unsuccessful treatuents. Some treatnents, made strict3-y accordingto instructj-ons and under high-1eve1 supervisione stil1 gave poor results. Further south in the Sikasso and loulount areas relatively good results were obtained. lhe Conaoe V ( roup6 ) 0n the wholc the results obtained ln the Conoe Ya11ey have been verygood. Infected flies were found at three places (r,otonsol I(afo1o and onthe Kinkene), but neverthel-ess, the situation ls very much better than ltnlght have been consitlering the situations in adjaceni val]-eys. The l,erraba Val1ey (Grechan and lont Eoutler) 0n1y one catch (fIZ ffi"s) rvas mad.e at Grechan before this polnt becaia.e inaccesslble. Further rrooth at the ?ont Routier, some very large nurabers of flies were record'ed- Although sone breaks in control were notecl in this region,these a.re not consj-dered to be responsible for the sustained high densitiesof f1ies. Althongh one lnfected f1y was captured at lounana, the results obtained.for the heatlwaters of the leraba were generarly satisfactory. The Sandaroa Vallev (maita.rra) fily nu:nbers fluctuated at high levels at many pLaces along the Bandar:ra and Bou, and along the adjacent ljzi. Although there uere some odd occasions when there r.rere brealcs in control- measures, for most of the month lntensive searehes couLd. not reveal anybreeding sites capable of producing such large and. vridespread adult popula-tions, The nurobers infective sta6es d.isturbing. of infected. flie ofO vohnrlus s (many of them containing more than 5found ln thls area vrere also very 2,7 EIIDIJT:IOIOGICAI COIiI $IDER-tTIClI: One can be fairly confldent that during July transmi sslon was broken1n the headwaters reglons of tire upper Banifing (sitrsso region) 7 the BlackYo1ta, the comoe and the leraba, and also along the lovrer couoe. ./. I -6- At the other extrer.re, transmission rates were und,oubteclly highthroughout the Band.ana Va11ey (inclu<ling the Bou), j-n the pont Routlerregion of the leraba, along the lower tTzl and the l-ovrer B1ack Volta. fn the remaining areas, sueh as the nid.dl-e BLaok voIta, the Bougourlbaand the lot'zer Banifing, the IeveI of transmission was considered to havebeen appreciably Lower than iluring pre-treatment times. fn itselfl the overall transnission pattern is sufficient eause forconcern. Ilolrever, the situation becomes more clisturbing vrhen one eonsldersthe level of infectlon in many of the flies d.issected. ,,1ong the leraba,Bandama and lower Blaek Volta, 11, 6 a.nd 2 flies respectively were foun6with more than 5 lnfective O.v-olvulus lazvae in the head capsuj.e; parasito_logical- situations that one-a-o6JilTexpect to find in sava*,a reglons.Along these rivers and elsewhere, many ittes with 3 or 4l-arrrae ln the headt, oapauJ-e were found. ,. DISCUSSION OII THE ?HASE T SITUATION - The lerge numbers of fliesr nany of thera i-nfected, that perslst ln partof the Phase I zone, have been regarded. by the senior stc.ff of the VCU witheonslderable coneern. rraced with such disappointing aehlevements a great amount of mentaL and. physical effort has been expendecl, in order to l6entifythe eauses of the problems and to d evise possibl" r"*uilial mer.sures for theeltuation in the shortest possible tj-ne. Sone problens now appear to havebeen resolverl, but it is very regrettabLe that the vrriter has to state that sotre serious situations conti-nue, parti-eu1arly with regard to the south-western part of the Phase T zone, and that no possible explanation oan yetbe put forward vrith any appreeiabl-e clegree of conviction. i{owever, in viewof the gravity of tl:e situatlon it seens very pertiaent to present here a summary of some of our thoughts and of the resutts of sone of our enquiries. There are app&rently four main phenonena that eoulci account for thenunbers of flies found ln parts of the Phase I zone. These are, Iocalbreetlj-ng as a result of control failures, Ioce.1 breeding in undetected conven-tlonal breedj-ng sltes, 1oeaI breecing in undetected atypical breeding sitesand i-nvasion of fl-ies fron outside the OCP control zoy!-e-t Eac! of th-6sepossibiJ.itles is considered separately beloiv: 7.I IOCAI BNSEDI ItrG PJ SUITIT.IG 3RO}.,I COI{TROI FAIIURDS r^ Despite the aecurate positloning of eorrect quanti'bies of ;\bate 2O9EC('Hroclcra/ aboYe some breecling sites, larval populations have not always beenelininated, To date, the dosage norually used has been o.o5 ppn for Ibminutes. ?ossibly this quantity and./or i.',is tine factor ore too Ion" larticularly d.uring the wet season, discirarge rates can fluctuategreatly and very rapidly' Iurtherrlore, water currents, especially aboveand below obstruetlons to flol, can be erratlc ar:d very aiificurlt to deter-mine. All these factors could adve:"sely affect the concentration of theinsecticide, its zone of vertica"l enulsification and its carry. Und.oubtedJ.ya suddlen rise in water level inrrecliately before a treatment is made, v7ouldplace at least some Lartrae at a depth at which they were unaffected. by theinsecti-cid'e" This is dlfficult to cienonstrate, for very obvious practical ,/. reasons, but never:theless there is no d.ouht that it doee oocu:r; and enablea1ow-leveL breeding. Simllar redueed k1I1s would result if the depth towhich the insecticiri'e t s physical propertlee allowed it to penetrate thewater, was reduced. l'rerlntnary laboratory tests at 0uagaio1,go,, on somebatehes of the ?roeid.a formulation strongtl, suggest that the bulk of theinsecticlde reuains in the vrater at a hilhlr 1eveL than is neeessary toreaeh al-I Ia:rrae that may be verticalty aistributed from just beJ.ow thewaterfs surface to a ileptrr or approxirrlt"t,., one metre. fhcsc tests arebeing continued and expanded, [here 1s no doubt that one ox nore of the factors disoussedl above hasbeen responsible for the presence of fl1es on the Banifing and on the BIae]<voLta in the Detlougou and Boromo-ouessa regions-- During august, double ttosingof sone of the breedlng sites in these a=eis wlIl- be camied out anil theresults rvilI be ygl{ carefully checked 1.e. two drops of the requlred dosagewill be mad.e at dlfferent intlrvaLs above each breeaing uite. In oti:er parts of the ?hase I aone, especialIy tn the Bandlama Valley,tletalled investigatlons lndicate that in alnost all cases possible inadtcquateperfo:mlance of the insecticicte ls not to blane for the p"uiurrc" of so manyfl-ies. some other expJ-anation has to be sought for thele areas" [hrou6hout the ycar and as hydrological conditlons change, breedingsites appear and disappear; sonetimes in regular fashlon, sometimes veryerratically. In vlew of the great amount of tiue spent checking all yratercoursesthat could' produee breecling sites, nev, urelding sites ire usrrally treateclYery soorr e'fter their d-etection. rn some cases, they are treated beforethe appearance of pupae. rn other cases at least o"l "y"r" of breeding mayhave been successfully completed, before treatnents can comnrence. Horvever,our experlenee has shorm that on the occasj-ons that this has happened, thereis never a large and sustained. iricrease in the f1y popuLatlon. rn the Banclaraa^t/a11ey, Y-qry-Elgilgq sunreys were nade of all wateroourscsoontaining vater. sma1l preii-o-usr$1frd6Tected Lreeding sites were found. on asmaIl urutarned tributarJr of the 3ou and on a sma1I tributary, the Garamon, ofthe lower Bc.ndama. Ilone of these breeding si-tes was oapabie of producingeufficient fl-ies to account for the high Ily a"rrsltles ieeordedl tfrrotrehottthe Band.alra Va11ey. 7.2 lOCr^TL BRIED i?ESUtrI G IRO]I UI.TDIIECTED CQI,ITENTIoII/rI BRDEDING 7.' locAt xRnEDrNG IN IN.TD]]TECItrD ATYP ICAI BRNEDTNG SIIDS one is a}vays eonsci-ous of the possibility that S..da^unosum may breedln plaees that are not typical for the species" Ilowever, very carefulchecks nade by Dr llalsh of a great nany unusual p)-aces in the BandamaVal1ey failed' to reveal the preser-ee of a single S. _damn-osug larvar pupaor pupal ease. -B- ,.4 INVX.SION 0tr1 Fr,fllsi tr,ROIi OUTS]DE TI.M OCI COi\TfROl ZONE It is rrlelL la:olrn that Sj, damnosu.4 can travel appreciable distances,both by tireir own active rrffiTTffu=y wind-assistanie f1lght" por thisreason j-t has aI',ra;,s been anticipated tha'b there vror-rld be sone infiltratlonof flies into the southern, south-vrestern and south-eastern peripherc.I zonesof the OCI zone. rn view of vrhat has been discussed in sections 7,1 to JrJ above, themost plauslble explanation for the presence of eo nany flies in theSandana, IrTzi, r,er&ba. and. lower Blacic volta valreys, i; th;i there have beencontinuous invasions of flies fron outsicle the ocll zone in a much more regu-larly lntense vray than previously anticifated Three posslble invasion processes havc been considered so far: - lov IeveI aetive flight - regillar relatively short distance wincl-assisted movements - fairry regula.r long distance wind.-assisted novenentg Each of these possibili-bies is consiclered separ.ately ber_ow. T,ovr levei active flights of r.l_ies nor th.',rards into 'bhe OC? zone fromrain forest habitats in ti:e sou-thern fvory Coast and G.hana, has a1vrays beenanttcipated, anci there j-s no d.oubt that there has been et least sone movenentof flles up the Band.ama and IIzl valIeys. Evidenee for this is tvro-f oId..fiirstly, menJ- of the flies caught on the ri'rers under consid.eratlon , hadO. volvulus inf ectlons that were ltuch more charaeteristic of forest S. dar:nosurnthan of tlte savanira forns" Sec,:ndIy, nLrbere of flies progressively increas edon a.nd up the I,Tzi, long before there was any flow of na ter i-n that river. ilven so, it seems extrenely unlikely that under their olzn volition, soIaany flies eoulcl-so.reguIi,rly penetrate so far irorth. It therefore seemsrauch more p:robable tllat whill "orau flies have aetively flovrn northyrards upsome river va1leys, others have i.re.en asslsterl ln their novenent by vrinds.rNvidence for this.h;npothesis can posslbly be r'ound. in the faet that on trvorecent occasions (cirea 24 and, lr-r July) itruro ,rur" sudd-en marired increases1n the nuirbers or ffi captured in aii.'i'erent places at the sa:le tiroe,strongly su'ggesting th:rt sone witlesprea.d extrinsic factor was exerting a fairlyextenstve effeet. ind-assisted flight appears to be the only acceptableexplanation. In recont weel;s two different types of wind have been suspected. ofassisting the novements of fLies. iire first of these are the prevailingwi nds vrl'rich resul t in relatively lotT altltude and coraparativer-y slovl movementsof air fron the coastal re6lions of .,rest.tfrica, north-west,;rard.s into thehiirterland' rt is coneelvable that these ni-nds courd assist the movenentof flies for distances of up to a fcw hund.red kilometres. ff this is thecaseJ then many of those flies fcund in the Band.ana and llzi vaI]e;rs, cou1d.easily have originated fro-r,r breecling sites in the ]ied Bandama. antt- lolrersassandra valleys; possibly a.lso fion il:c cavally j?iver r,;l:ich forr,rs thecoastal frontier betlvee,' liberia ancl the Ivory coast. This coul-d also -explain the hrgh infection rates recorded ln fl-ies captr.red in the BandanaVaI1ey. ,/. Irly rlovemente assisted by the prevailing vrindo ulght, in slnilarfasition, account for the higir f1y nuubers 1n the lolver BLack yolta valJ-ey,although in view of the vasi and conplex potential breeding sites in thisregion aird' the inpossiblllty of being aule to check aLI of thenl one cannotrule out the possibility tnlt trrer" lravo been soue control breakdowns inplaoes. I further possibJ-e explanation for higle fIy nunbers in parts of the?hase f zone, is that flies are being uroulirt in on fast-movlng easterlywinds tha-u are invariablJ, associated lzith storus and ver;r turbulent airnovem'ents. As the nunbers of flies recor<1ed. in eentral Lhana in recentweelis arc not great it nust be assumed. that any flies carried. 1nto, forexaupler the Ba.ndama valleye had their origin in the tosi/Danomey $avannaGap region; a distance of soiee 8oo lrilonetres. ?arasiiologieal findingsdo not support tl:.is rather ini:robable posslbility. Ilolrever, it is apossrbility tirat we cannot afford to overLooli. Past experience in several parts of ;\frica has denonstrated ti:etremend'ous technical difficulties involrred in trying to nonitor movements ofS'..clgmnosir-:lq flies, a.nd in most cases tire efforts-and expenses involved havenot been justifiect bJ' thc extrenel-1r poor and./or inconclisive results obtained.it is likewise beyonri our resources to attenpt to study f1y rnovements i.n anentl'eavour to clarlfy certain situations in the southern poit or 11re lrhase rzone that are appa"re:.rt1y dur: to .rovenents of flies from outsidc the treatnent ?les' Ilowever, by exanini-ng al1 the facts o,s they appear to us in rerationto the v'rious possibillties, we can say v.,hat seei.s lrost probable and whatseems equally most iuprobable Ilaving done this, we feel that vre nust glvemost surpport to the hypothesis that rr"ry flies have entered. the sougrernpart of the Phase I zone, mainly by tireir ov,rn active flight, from foresthabltats in the soutl.r of the lvory-Coast and possibly Ghina" ,.je are alsofairly sure that from time to tlnl inraigration has blen faciritaterl by fliesbeing assisted. in their tlover.rents by rirnds, probably also from the forestbeLt. llhat seeras nost j-nprobable, is that'tilere has been any breeding inthe Lovrer Phase r zone capabre of produelng such high :fIy nuubers. It is therefore concluded that: - in tire north of the Phase r zone rzhere there have been a few controlbreakdovrns, the situation can certainly be regularlsed vrith ourpresent resources; - in the south of the lhase I zone we can expect, fron tine to tine,invasions of flies vlhich are beyond. our resources to prevent. -9- 4. ],RXPAn TIoNri ro]i ?iilSD II COI{TROI OP"IRI.T rol,rs The ?hase If sectors and. sub-ilectors ho.ve functioned. reasonably welland very valuable pre-treatnrent entomological data lras been collected. rilthough breeding has conti.:ued on nost of the suitable rivcrs innortnern Lrhaira, no irl;rature stages of s-_ gqgnosl+g were found in upper volta.Hovrever, flies were found on the ror,verEE-EE-Tite volta rivers i-n thesourth of Upper Vo1ta. 5everal were infected. one f1y was found with 11 ./. 10 infective la:srae of O. volvulus and another with 9 larvael suggesttng thatpossibly soutirern Ghana.sone flies had. origi nated fron forested areasi 5, IRtr]}ARATIOT{S FOII IIL''^SE III CONTROI, O?;lItriTIOi{S At the beginning of tl:e nonth Dr l't.I,e Berre visitedl Togo in order tobrief the 1'uthorities on progress to da-te in the ?hase f and, ff zones, and.to dlscuss arrangements for opera.tions in Togo durin6 lliase Iff opcratlons(recruitment and training of iersonnel, opening of Seetors ancl Sub-sectors etc. ) ii copy of Dr r,e Bemets roission report is attached hereto. Evalu-.'tion personnel of Yendt Sub-Sector ha.ye connencetl surrreys todeteruine suitable catching points and checktn6 sites in the oti vllrey. 6. OTIIEF- }I.|1,TTERS 6.1 BUII]JIIIGS I'lodificr-tions ancl extensions to the Bobo Dioule.sso Sector garage havepro8ressed at a reasonable rate. Rewiriirg of pr-rt of -bhe llobo DioulassoSector office lvas successfully completerl. zrnd it is no'.,possib1e to useseveral eLectrical appliances at the sa.ne tirne Thc or.rrer of the iiorhogo :iec'bor offiee finally gave iris approval forthe construr:tion of a. ljector garage on his prer-rises, and arranger;rents are nor,l rrell in ha.nd for coriri,iencini; construction. 6.2 SI.IRX :',',nTS FOR VEIIfCIES :\]iD Otl-trln gl-l?f'lfIr"S and of During the nonth, Ilr D. Iicho!.I had no.ny ad. hoc meetings vr"ith the LSOChief of Suppli-es, with the result that tE?procedures for taking rec@tsupplies and for tireir distribution, have been appreeiably streamlined. Trar$e and very welcoue batches of vehlcle spare parts and tools werereceived, a.nd have novr been ctistributed to the Bobo gs.rage and to I(orhogoand Sikasso offices. 6.7 VCU-II'I STAFF Dr R. Ie Berre (Cnief ot a"nd i:Ir I,!. Traord (Secretary) Iilss C. i.'llson (.,idninistrative Assistant)leave during Ju1y.Unililere t),on An Assistant Draftsman, LIrUnit I s Ouagaclougou off 1ce. B. 5616, vlas recr;-'-ited. and installed at the 6.4 VISITORS L[r ]1. Ilodson, COPR entonologist, worlied with staff of the trntomologiealEvaluation iletr,vorlr during Ju1y. In the }hase I zonc, he participated ina.erlal surveys and, breeding site checks, whl1e at Tanale ire obtained experience in dissection techniqiies -11 - 6.5 Bupgpr ESII]'TJITES L 976 0n 28 Ju1y, Dr representatives ofUnits, at a neeti-irg i:iaIsh and the writcr joined the progranru.e Director and.the ri'inance, rersonnel and Epiderrtological -valuationto d.ilecuss budgetary provisions tor t970. 7. CONCTUSTO}TS .During Ju15,, five eycles of aerial larvicid.ing operations werecompleted rvithout any najor probleras arising. ijone were conducted. usingonly helicopters, but later in the month, a fixed-wing aireraft was bioughtinto ope:ration to treat the larger rj_vers. - In soinc places the results of larvicld.ing operations have beenexcellen-b. 1"1y nun.bers have been extremely Low and transnission has beeninterrupted. In otlter places the results vrere irot so good. Due lrrgely to an lnade-qurate perforrnance of the lnsecticide, b::eecling was not ahvays prevented,with the result that f1y nui-rbers incr.'eased and lolv level transmissioneontinued. In the valleys corr.cerneil, i.e . the lJaniflng, ancl the Ded.ougou,Boromo and' Ouessa. regions of the Rlach voIta., the situation can probablybe regularised by clouble dosing some of the more troublesome breed.ing sites.IIowever, this is not a xteasr-lrc that one can visua.lise being used. on a 1argescale. [he insecticid.e for::rulatlon in cument use is very cost]-y ancl the'nanufacturer is not ahvays able to supply his product yrel1 in ad.vance ofwhen it is rcquired. The search ror an a.lternative inseeticitle vrhich i.seheape:: and which can be formulateri by more tl1an one nanufacturer shouldtherefore be given priority consideration. Recent svents ln some southern parts of the Phase I zone have sholm thatltot'rever effective l.arviciding operations ne.y be conducted., the results canbe named by the lnrnig3.1ion of appreciable nuinbers of flies into treatedzones' '''nether or not these rr:-grzrtions occur each vret seagon and. to whetextent they roight possibl;' affect the ?hase Ir and fri zones, are unknownquantities. Horrever, the sitr-'.ation will be i:ep'b under very close surveillance andevery attenpt will be road.e to obtaln further cla.rification of wha.t has beenhappening, in order thet a f'"riI assessr*lent can be made of tite possibleimpaet of Ie.rge-scale fly migrations on the objectives of the programnle. D.,^i.T. Baldry Acting Chicf, VCU Ouagadougou 12 August L975 ,i ,,l/hti! 1 ocPrtcu Hellcopter 58005 Hellcopter Iota].s Ih1l-Sorter i[ 5102 I f00trIJS IER @ivT AIRCEAflT EIlIEIU ECTIHS ---.- Jry.-r.grq 84.7 0 ,2,o 116.7 1.7 1I5.? LcT 3r.L 0.5 L4.2 L4o2 tl. O Chlef VCU cldy U6f,1639, Report 0 0 00 00 TABIE 1ffi 102.0 86.4 9j.1 12ro ,L5.6 ,6.6 ,52.2 0 L97.2 62.5 0 00 100 Alrcra^ft ld.nl n. Totale HeIlooBter erzTl &artrfctdfng 102.o Surveys 0 v.r.P. 0 Ilc].lcopter L{ 79?9 J 0 1.? Hellcopter 59558 9512 22o4 219.6 I u, d +,o E{ @ aAAl r<1 rn !o aHootr\ lr1 a EOl F{ \o a F{o\ OJ @ A Ptl\(\I fl atn @N ro e stn o a $ |J\ a Hd!H {,+ 6J \o aoo\ C\I rt a(\, o r€, rnt @rrl or (\' ,o (\I dFI t- a FIo\ @ (\I a!n+ o a(,lo r.n or o!r\ .+t+{-l tn a Ol .+ r.- o a(\l!r\\o e r.\ a Fl @rn r{ +to E{(\, F{ O tsoA F{ \o aod e- F -a F F.l co F{ a FItu E trit-{ fio ProEE' Bfr q{ .P oIl B,q Ei? HI BIal HI HI Hi el n HiE HI r-r I etl EI .Fl Na .c, fl g 0r idbE ffdb- o-89g EgtoEt ?SA EBE}.?(t EHgdP{Opl(l di,P-F{}doto{t Ct r{S H€Fq0q(I, r{ .. Cq HH H.. t{hr{ooo+r {t {,ElE,{oooocrA r{T{dF{AAoo0)trtriEt HH t{ o +l B'oo .r{ Fl 0) H H t{o {J P.o C} .rl F{ o T,tn ol HN UA Ho 6 B *<()o I I I I I I I I t h o fiot .rl r{oH o d{5o E{ q c,\-r N =Eo q hJ t{J E tU ,\ 250 200 t50 100 50 /.0 30 20 t0 0 VOLTA NOI RE / BUI -AREA 0 2 20 SEPT. 0 20 JUIL. 20 NOV. 20 0000 ocP/ VCU AOUT 1975 0 0cr. t0 DEC 268 I tl ll VOLTA NOIRE - CHACHE t50 2s0 200 50 1.0 20 t0 0 a5o x =oI x trJ t00{l{J Etr\ 30 JU IL t0 20 AOUT 020 SEPT. 020 ocr. t0 20 DEC. I 20 0 0000a ocy'vcu t975 NOV voLrA NOI RE I PONT DE SAMANDENI250 200 q)o \ l{ : =o -t t50 t00 n UJ tutr 50 40 30 t0 20 0 20 JUIL. SEP'I ,0 0000 ,0 20 20 I 0 oce/vcu AOUT '1975 0 0c,l N0v. DEC. 250 volrA NOIRE I PONT DE SAMANDENI q5o \ lrJ E =o \nlrj trl t{ tL 200 t50 t00 50 /.0 30 ,0 20 0 I 20 JUIL. 0 ,0 20 SEPT t0 20 0 00000 oce/vcu AOUT t975 Gf. 2A N0v. DEC. q o \ l{ e. Eo (n t{ trj u 250 200 t50 ,00 50 BAN IFING . LAMPASSO 20 lr0 20 30 0 10 t0 ,0 000000 JUIL SEPlI 1975 ocP/ vcu AOUT 0cr. NOV. DEC. COMOE . TOUPE250 200 S tso C) \ tU =oT (D trt il H 't00 s0 10 30 20 t0 0 200 20 JU IL. t0 20 AOUT t0 SEPT, l0 20 ocr. t0 20 NOV. 00000 DEC.0 t975ocy' vcu t LERABA - GRECHAN q5o\ tu E Eot" .l{ trl E !.ul{ 2s0 200 ,50 t00 50 t0 30 20 t0 0 . TERMINE t0 20 JUIL (ruaccess tBLE) t0 20 SEPT. t0 0cr t0 20t0 0000 ocP/ vcu 0 AOUT t975 0 N0V. DEC :!!ldrt'1d+{+r- 4d*,+M6il'w-'ffi#,trtffi*rr?ffiraa'!?Fn:n 7=rffil1#E* HjeatiF*ll ft 250 200 t50 t00 50 30 20 ,0 3 0 JUIL 4 I t q5o \ tU E o\ tn IIJ\, tq e.tu u LERABA PONT ROUTIER ,0 20 0cr lr0 0 20 SEPT t0 20 DEC. 20 0 0000 oc P/ vcu AOUT. t975 0 NOV. / CHAUSSEE DE BADIKAHA Q)o \ tU =Eo \ fl{ _lt{ tU u- 250 200 ,50 t00 50 lr0 30 20 t0 0 t0 20 JUIL. 20 SEPJI t0 20 oEc. 20 0 000 ocP/vcu 0 AOUT t975 0 0cf. NOV