Briefing of 13/2/84 concerning results of the 5th and 6th weeks (30/1 to 10/2) and proposals for the 7 th and 8th weeks (13/2 to 25/2/84)

touAcA - vttMoRANDUM To Dosdier Baûib Brlefing . Date 13 lbbnrary 19e4 a.t Àttantion ING Subjoct À}TD From Dr Our ref, ÿeV/O225 . Your ref. Originator (2) OP S$nce the lower Conoe'population has üot disappeared on its ouc rlue to 1ow water, the Comoe will be treated with Tehrar'beginning in;the 10th week. îhe T.,eraba w111 be guqpenêed beginning j.:e the sevênth week. The Mia and SôuaÈ Blvers will be, püt untler Telolar treatment trntlI further notlee (sée dlscusston unaer goua.kg below). r îÀsc@t I ., (r) (4) (:) (r) Banako. (z) '@sibility of,,trea'tment by boat will again be explored." Àt 66a1/see.; this shouta "be possible. Àt SêIingué, where 6 fLies wêre caughtr. the authorlties.will bd coutacted to plan a manipulation of the fÏqod. gateB to dry Up' the spi-Iarây. Àlso, a detailed pnospec-tion of the lrrigqtioüx èanels-.sonrre'cted with the clam will be eamied gut. : "Bobo. ,Although the lorer Afact VOlta has e'easecl to flow, there ib ffinsÈderable f1ow. (4romÿgec) at the level of lIwoky, where a few larvae ir'ere,.found irt the 6th week. A manual tréatment r,îith tenephos was eaÉ,fied o.$tr I t t' -' ?0 fliee at Tl,enfala indlcatecl a eerious treatment failure. Regu le .o CIos .t .../?. . Â1I aerlal treatments in thê Eaetem. Bæe a,ne 'to lie sr:spend.ed. ' . be§{.nnipg in thq ?th rréek. Mânrlal tpbatnents. 111.1 bp carfed out âs needed. A ôare.n11 watch wiII. bè kept on the lover parts .qf the Oti antl IÿIrLte Yolta Bivers jr: order to ldentiify and trept.(**t al}f tf poesible) breeding sites çhieh Uecoüe'àetive as the LeræI of tÉè VoLt#i,ahe contlnues to drop. Ip thè treateil part.qf the;:I{estern Zone, results continuéd.t9-b" excellentr'with:some smalJ. eic'eptlons whleh rÉI1 be'discussed ia relatlon : to eaeh seetiiri. '. :'t. ' i. 1, ''Thê..folJowing nodlfilêattong ln treatnents were risrâe: ([]) fire.tomoe will be.'suspentted froin Groümania down to its coafluence . with the Qior.lré beginrrXng in the sevêirth week. [he flow ls very weàk and there'fçme14 only 2 or J potential- bree.cting stteg'. Ehe Saisandra belor, the Bagbe will be suspended beginning j.r1 the 'seve[th week to allocÿ for reeolonizatiorl before the trial of pera ' nethrin begils. À member of the Hyd:robio1ory lean will prospect the rlvet this week to eonfj-ra locatlon of".the nonitoring points. È' lr 2 (t) }oua.l<é. An exterrsive 6roi.mri. prospection was un<lertaken in the GFfa subseetor to try to ldentify the sorree of flies being caught at I'ogualé. In the T,obo basin (r.mtreated) the ?outon, Goré, Goui a:rd the lobo itself !,yere prcspected at l'5 points. 0n1y the lobo was for:nd positive, at ?etigpa Pont near I,oboville. Ehis site lvas densely positive in all aquatic stauSes of S. danruaosum. ?upae frora this site (252 females) yield.ed 6iX 64 ffig@o> vring tr-rfts oa 1VL A seconcl srmple tal:en on 7/2 (4?5 fema:es) yielded tfr oL, 1,4, oz, lfl ol, 24:1 04 and 67f" 05 rving tufts. îhe Sassandra river itself (r:ntreated) rvas densel;r positive at llawa near Soubré. 51 pupae Jrieldecl 50 05 and 1 04 vring tufts on 3VL. I(operagui 7 lcn upstream of Soubré rqas also densel;rpositive but the dam spil-I\i/ay at Buyo was negative. In the Ntzo basiny logurale itser:8 was lig;htIy positive before treatment but negative aftez-,.,rards. The G.bé and tile llrzo itself urere ne6ative. îhe llia, the Cavally an«1 the Go (aff un- tz'eated ) were all posf i;ir.e in !. 1!341ro*, . 38 fenales 'r,sere energed from a saraple of pupae taken on A/2 on the L[ia. lhe sar^npIe,,"ras 15 O1, ÿ,02, ]-5fr 07, * 04 a:rtl 53% O5. A sa.nple tal;en on the Cavally Ï:ad not yet been arral;;7scl. ltrumerous sna1l affluents of the Sassanrlra we1'e prospected, inclu-di-ng (fron: north to south) the Iloui:rr Ki1o, I'Iiéhi, l,,Thien, anid Son, All lvere for.,nC nef;ative. Iurtl:er to tire nortirr'the Souan, a. smal-I affl-uent oi the 3afi-ng ri,as foLrnd to 'oe positive nea.r Gu:essessor 0f 1, females emergilg, J vrere 01, 2 02, 5 A1, 104 and 4 05. Itro report n'as received concemin6 the Eaba mentioneâ in the last briefing. Consicierin,3 the ensemble of tliese results, anô lackin; tl:e resufts of crrtota,.:ononie identifiea.tion, it vras deeitled to put under lelcra-r treatrnent those arees which seemecl , fron the vrisgtufts of the energed flies, to harbol.:.i soi:e proportion of sava::nah speeies or g. sqliamo§r]I. These trea.tments were justi- fied on the basis; oi the residr:-al- transr;,ission a.t logouald. Treatment of the lobo couItl be justifieC on the basis of the rrclean-uprf of the resir-:tarrt strain (see ttsu;;eeptibllity tes-b5rrg[ belor.r), but it was deci<iecl to pu"t off treatment r.rntil a seconcl series of susceptibiJ-ity tests can bc earrieii out. S us c e pt ililiti'_Fe s ti:rg : (f) The population in the Sassa:rdra at i(operaeui was for.urd to have nornal susceptibil j.ti, to boti: tenephos and ehlorphoxim. The larvae from the lobo seen rcsistant to temephos, the on13r nroduct tested. I.iore tests rvilI be done in two weels. (z) .../). (, aI z (l) In the 7th week, ti,e IJé1 Agneglryr æd Bolr.bo vrill- be prosirected b;,' ai-r and the larvae tes-teil ','lhen fou:d. Insectieide trials: The Ielo:ar SC95 and YilB5-27 formul-ations rl'ere tested on the Bagbe on te/t/A4. Botir products are promisi:rg but furthei' tests are needed. rvi':,en river disci-iarges axe higher. cc: Chief YCüf Dr. R. Subra Chicf Evaluati-on Chief Zone ],Test Ch:-ef Zone East Chief, Bouake Sector Chief, Àerial Operations 1[. Pan;;alet, Bobo l[. J. Pouth-Pouth, trara