I WOLRD HEALTH ORGAMSATION AFRTCAN PROGRAMME FOR ONCHOCERCIASIS CONTROL ONCIIOCBRCIASTS VBCTOR ELEMINATION PROJECT BIOKO , BQUATORIAL GUINEA GROIIND LARVTCIDING OPERATIONS JANUARY.MARCH 2OO1 By R.MEITR Temporary Advisor Scharpcnbargsweg 8 21149 f{amburg tel : 0049-40-79752624 fax: 0049-40-79689196 c-nra il: rolmey@usa. nct April2001 e i,/e tr ,' a . ,i /t(. [/)o c ', ;t I 'e{* L For Action To: TCC,,13 1''.) r.r o.?{^'.Ho-- -( n!f, (e- f- CEVq i- t ruh/rr'r/- " { Qt 6'-t'< ! ' !/!,'; 1, n'tl '' Ledn '/) (.-r,.77 , .t(r c ,'t t F.,lt ( ut ( IN ,l 0 r^l i t1 0".For lnfornroticn To, -), a. r- '-.i--, -t. Lhi RECU i I MAt 2001 A.POC/DIR (l c..Q nt € e-. l2tHurt ". .i-itt I t) Z r lo5 a ?e a t t t ITABLE OF CONTENT 1.0 INTRODUCTION......... 1 2. O RIVERS, TOPOGRAPI{Y AND VEGETATION.................. 1 3.0 PERSONNEL, MATER[ALS AND METHODS.. 3. 1 Personnel........... 3.2 Treatment maps.. 3.3 Treatment points. 3.4 Insecticides....... 3.5 Spray equipment 3.6 Ottrer equipment.... 3.7 Training of the personnel........... ......2 2 J 3 ,4 .4 .5 a , .........5 3.8 Treatment.... 4.0 OBSERVATIONS, RESULTS AND DISCUSSIONS 6 .7 8 3.9 Aerial prospection of Southern Bioko 5.0 CONCLUSIONS AND RECOMMENDATIONS Figures Plates Tables 9 l.INTRODUCTION The island of Bioko , which is part of the West African State of Equatorial Guinea is heavily infested with a forest form of Onchocerciasis. A large part of the local population is infected with the disease. Due to the isolated position of the island the African Programme for Onchocerciasis Conhol ( APOC) has established a project to eliminate Simulium damnosum ( S. L. ), the vector of Onchocerciasis, by treating the aquatic larval stage of the vector with larvicides. A formulation of the organophosphorous compound temephos (Abate 20EC) was chosen as larvicide to be applied to the river brpeding sites by helicopter. After several years of research and preparatory work a pilot project was set up in the dry season of the year 2001to treat the accessible parts of the rivers from the ground . The project was limited to the inhabited Northern part of the island since the Southern region is completely inaccessible by road or on foot. Out of approximately 100 rivers in this part of the island only 30 were flowing, consisting of 7 large complex systems with numerous tributaries and23 small rivers. The objectif of the project was to collect information on the activity and behavior of the product under operational conditions, considering the specific conditions of the rivers on the island .10 technicians were trained to apply the product by knapsack sprayers. Treatments were monitored by regular pre and post-treatment prospections as well as weekly vector collections in key positions around the island . Parallel studies by other teams were set up to accompany the vector control activities. They were : i. Cytotaxonomy of the vector, ii. vector insecticide susceptibility, iii. distribution and altitude- limitation of species, iv. hydrobiological monitoring of the effects of regular larviciding on the non-target fauna including fish and prawns. The outcome of the ground treatment will serve as basis for the planning of the combined aerial and ground treatment eradication project next year. A helicopter flight was made to the Southern uninhabited part of the island to get a first impression on the terrain and the flow of the rivers. 2.0 RIVERS TOPOGRAPHY AND VBGETATION The island of Bioko is of volcanic origin.Three inactive volcanos , rising to between 2000 and 3000 meters above sea level , shape the island which is only 2000 km'? in size ( Figurel ) .Due to high rainfalls the island is densely forested . Considering the topographic and hydrologic conditions of the island , rivers can be characterised as follows: i. Rivcrs are numerous . More than 200 streams descend from the steep slopes of the volcanos. Horvever, during the annual dry season from December to April many of them dry up completely. t o /-'\ "\-.z t 1 ii. Rivers are short and small in size, often with few or no tributaries. Even larger systems do not extend more than 20 km . The majority of small creeks is lesi than l0 km in length.iii. River discharge is low. During the d.y season it ranges from a trickle to approximately 5 m3/s. Only three rivers in the South of the istand (Iladyi, Moaba, Ole ) were observed to have a higher flow. Discharge of the majority of th" rivers ranges wellbelow I mr/s.iv. Al[ rivers descend from the steep slopes of the mounlains with gradients of l0% or more. v. Flow is fast and turbulent . Generally it ranges from 0,3 to more than I m/s .vi. River beds are rocky, ranging from large boulders to small stones and pebbles with a continuation of falls, rapids , smooth rocky channels and intermiuent small shallow pools. vii. Water temperatures are low,mostly between l9 "C and,24 "C . viii. The water is clear with turbidities below 5 NTU.ix. Streams are covered with a dense bank vegetation or thick fringe forest . Overhanging trailing leaves , branches , roots from riverine vegetation , fallen trees and large amounts of dead extraneous plant material supply ideal conditions for larval support . However, compared to our last visit two years ago , large changes have taken place . The forest is being cut at increasing speed. [n many places the prime forest has given rvay to fields , plantations and open bush land ( Plates t-24) . There are about 100 streams large enough to be treated in the inhabited part of the island . Out of these only 30 were flowing sufficiently to be treated at thl time of the project- 7 of them are.complex basins, most of them with numerous tributaries. The large rivers are : Ruma/Grande , Musola , Tiburones lLada,Maloho, Apu, Tiburones fl and Matadero. The other 23 rivers are small , often without any tributaries. ]hey are : consul ( contaminated, not treated ), Ericorico , co , Toco, Suhu , Ebehe,[opa, uba, sabo, Machuchumuano, Boba, Builo, chike, Esaa/Rupe, Laric,biala, Balaopi, Mirupururu, Mopobill, Sampaca, Timbabe and some name and codeless small springs ( Figure 2 A-D treatment maps ). 3.0 PERSONNEL, MATERIALS AND METHODS 3.1 Personnel A total of l0 persons was required for the conduction of ground-larviciding operations in order to form two treatment teams. Each team was to consist of one teair-llader/ head technician, three technicians and one driver/technician. One team-leader and five technicians, who had earlier been assigned for other tasks were reactivated.They formed the core of the team.The second team-leader and one experienced technician were seconded from thc Spanish Cooperation/Ministry of Health for the duration of the project. Furthermore, trvo of the project drivers joinded the team . They are: 2 a Team I Simon Abaga Ekwa Enrique Mba Ondo Alejo Ondo Mba Juan Luis Alfonso Francisco Bururu Team 2 Rufino Nguema Andeme Arcadio Edu Miko Jose Manuel Mba Adjam Antonio Esono Anvene Diosdado Olo Motu Team-leader, Mi nistryof Health Technician, Spanish Coop./ Ministry Technician,also dissection, APOC Technician, also dissection, APOC Driver/ Technician, APOC Team-Irader, Span.Coop. /Iv1inistry Technician, APOC Technician, also dissection, APOC Technician, APOC Diver/ Technician, APOC The drivers rvere fully integrated into the teams and also hained for insecticide application in order to step in when there was a shortage of technicians due to illness or inavailability . The technicians also had to participate in vector collection, training of village collectors , fly dissection, assistance to hydrobiologists , susceptibility tests and river prospections. The training lasted for two weeks , but continued for two more weeks after the start of the treatment operation. The training was conducted by R. Meyer with the assistance of the rest of the expatriate team. 3.2. Treatment maps Treatment maps at a scale of l:50000 had been established after previous visits to the project area. All rivers were coded similar to the system used in the OCP . Besides , all conceivable treatment points were entered and marked in numeric order ( Figure 2A-2D). 3.3 Treament points In January 2001 all previously established treatment points in the inhabited part of the island were visited and the points confirmed . New points , which had not been visited before, were added and the treament map adjusted and completed. But even later, after the start of the larviciding operations, new points were discovered every week. Many points were diflicult to access and involved long drives and walks along forest tracks. Eventually 248 treaments points on 100 rivers were established . These also included rivers which were not flowing during this year's treament operations. But due to seasonal changes in the pluviometric and hydrological situation it was considered necessary to include all rivers. At each point the river condition was registered and the amount of discharge, water temperature, pH and conductivity were measured. Preliminary prospections were conducted to gain information on the Simulium breeding situation .All relevant information was recorded ( Table I Pages l-11). q) a 5:1\-t 5 aThe code number of each treatment point was marked with blue oil paint in a clearly visible position, preferably a bridge or tree to allow easy identification at each visit. The operation took two weeks, until the end of the week 6. All technicians and drivers participated to ensure that everyone became familiar with all the points. It had been planned to treat all rivers up to a height of 500 metres above sea level , the presumptive altitude of S. damnosum breeding. But ground access was limited and no river could be treated in full. And with the exception of the Musola and one of it's tributaries the Eba , no river was accessible up to the 500 m level. Even at lower levels many rivers were partly or completely inaccessible. On 30 accessible rivers with sufficiant florv a total of 92 points were selected (Table 2 Pages 1-11). 3.4 Insecticides From the posiwe experience gained in the OCP the organophosphorous compound temephos ( Abate 20 EC ) was chosen to be used as larvicide . A series of susceptibility tests revealed full susceptibility of the larval stage of S. damnosum ( S. L.) against the product ( Report T. Bano) . Parallel river treatment experiments showed satisfactory compatibility against the non-target aquatic fauna ( Reports of Hydrobiologists ). The operational dose was set to 0,4 litres Abate per m3/s of river discharge . This equals 0,133 ppm temephos active ingredient ( ai ) per 10 minutes . The decision to use 0,4 Um3 was taken by the expatriate team after evaluation of all data and consideration of the agravating river conditions like: relatively low prevailing water temperatures (19- 24 "C ) and a reduced activity of the product under these conditions , low river discharge , fast flow, high turbulence and rapid dispersion of the product. 2000 litres Abate , 500 litres Bt ( Bacillus thuringiensis H14) and 40 litres Rhodamin had been ordered for the project. The product was sent by boat . However, the container got lost and the product arrived towards the end of the project only. 150 litres Abate were then sent by air as emergency measure. The Bt was to be used as experimental product. It would have been interesting to learn about the activity and carry under the prevailing conditions . Rhodamin, an intensive red dye , was meant to be used for training and demonstration purposes. An amount of four litres of product, which had remained from previous year s work,.saved the situation. 3.5 Spray equipment. Five lever-operated knapsack sprayers - model Berthoud Cosmos 18 - were purchased to carry out the larviciding operations. The Cosmos 18 is equipped with a hand-operated piston pump, a pressure chamber and a lance with an on/off trigger-valve. We removed the spray nozzle because it was not required and it simplified the operation.The spayer rvas chosen because the specifications ideally fit the requirements of the project. They were: i . Light-weight and comfortable to carry over long distances with up to 18 litres of liquid ,ii. simple and fast insecticide application, iii. relatively correct calibration of srnall amounts. The capacity of the piston is 0,08 4 litre ( 80 cc) . This is the amont applied with one stroke of the lever. iv. Non-corrosive against concentrated larvicide formulations. v. The use of the sprayer is easy to understand. No dosing, timing or gauging device is required and dosage calibration is correct to an acceptable level. With the background of these figures in mind it was easy to adjust the application to the project requirements. 3.6 Other Equipmen, * lricn) Three relatively nerv Toyota Hilux double-cabin pickupslfiil been bought for the project were at our disposal. Furthermore one landrover was given to the projet by the Spanish Cooperation until the depature of the hydrobiologists. In cases of emergency the WHO Representative gave permission to use a WHO Toyota Hilux in the Malabo area.The number of vehicles suffrced to carry out this year's programme. In the coming season one more vehicle will be required for the aerial operations team ( pilot , observer, mechanic ). Two chain saws were bought to facilitate access to many abandoned and overgrown forest paths. They were of good use. Togehter with the insecticide a large amount of field and laboratory equipment was shipped from APOC/ HQ. Besides the fact that it was sent too late to arrive on time it got lost on the way to Bioko and arrived after termination of the operations only. Many provisional arrangements had to be made to overcome the lack of equipment. The absence of an Ott-meter, a precision device to measure river discharge and flow- speed of the water , which was urgently needed for calibration and training purposes, was considered a particularly serious shortcoming. 3.7 Training of personnel With the start of the training the team was moved from Malabo to Luba. This brought many advantages. Luba is small. There were no transport problems because vehicles were not required in town. All locations were in easy walking distance. All technicians stayed together in one hotel , close to the expatriates.The hotel of the expatriates had a spaceous hall which was used as office, meeting room , laboratory and store. All equipment was stored here. Early departures in the mornings were possible. And every night at 20 hours a meeting was held to discuss the programme for the following day. The majority of the important rivers is located in the South , closer to Luba than to Malabo , rvhich facilitated the work considerably. The training of the personnel started in week 5 and lasted for four weeks. During the first two weeks of pre-treatrnent training the handling oI the knapsack sprayers was practiced. The treatment points rvere visited and marked and at each point.Training s l f-1 5 applications with water and Rhodamin were condudted. Rhodamin was used to demonstrate flowdynamics of rivers and the dispersion of the product in the water. Treatment mistakes became visible. Treatrnent with Rhodamin also taught the staffthe careful handling of the product, because carelessness showed up immediately and resulted in red stains all over clothing, body and vehicles (prates t-24) . The correct use of thermometer, pH-meter and conductivity-meter was demonstrated and practiced. The use of a flow-meter for river discharge measurements could not be praticed as the device had not arrived. Measuremens with cork float and stopwatch were made. Two chain saws had been bought and the correct handling was practiced. Forest tracks frequently had to be cleared from fallen brush and trees. 3.8 Treament Treament commenced in week 7 , Monday 12 th Febuary 2001 and confinued for five weeks with weekly intervals.The first two treatments took four days each to complete . The work was conducted as a continuation of training and familiarisation and the whole crerv worked as one team. The treatment schedule proceeded as follows: Day I : Musola and Luba area Day 2: Ruma/ Riaba basin and East Coast Day 3 : West Coast from Tiburones I to Tiburones II Day 4: North Coast and Malabo area. In week 9, with the start of the third treatment , two teams were formed and the workload devided in two .Treatment then started tuesdays and lasted for trvo days only Team 1 treated the Musola and the West Coast. Team 2 did the Ruma/ Riaba / East Coast and the North. After two weeks the circuits were exchanged between the teams. For treatment purposes the river discharge at treatment points was estimated and grouped as follows: < 0,01 m'/s > 0,01- 0,05 m3/s > 0,05 - 0,1 m3/s > 0,1 - 0,2 m3/s etc. Discharge in the 0,01 m3/s category was considered too low to support beeding of S. damnosum and the carry insufficient for treatment. The rivers were not treated. Treatment was set to 0,4 litres Abate20EC per m'/s discharge , which equals a dose of 0,04 I ( 40 cc) per 0,1 m3/s. The srnallest possible dose to be applied with one full stroke rvas 0,08 I (80cc) . Consequently the product rvas mixed with water at a ratio of l: I , rvhich reduced the amount of product per stro ke to 0,041 (40cc). Each team was equipped with a copy of the treatment table rvhich stated the river :0,01 m3/s :0,05 m3/s :0,1 m'/s :0,2 m3/s 6 discharge at each point ( Table 2 ). The technician simply had to apply one stroke of spray liquid per 0,1 m'/s discharge and then enter the number of strokes into the table. Calculations of the amount of product to be applied were not required and sources for rnistakes thus eliminated. Rivers in the 0,05 m3/s group were also treated with one stroke until the technicians had learned to apply smaller amounts than 0,08 I by just opening the trigger -valve and allowing the product to slowly pour out by gravity without pumping. Many treatment points could only be reached after driving to a central place and then continuing on foot to one or several far-out points. Rather than carrying the heavy spray- unit to each place the correct amount for each point rvas poured into small containers and the points were visited and treated by bottle. Some places like darns , which required the application of large doses , were treated by bucket ( PIates 1,-24) . 92 locations were treated and a total amount of approximately 21 litres larvicide applied per rveek. Almost 90 per cent of the amount went into 7 large rivers with 51 points and only 10 per cent into 23 small streams with 41 points. Originally it had been planned to conuinue the treatments for a total of 12 cycles. But after five applications the treatment rvas stopped for technical reasons. Nevertheless , the aim of the project - to learn about feasibility and the impact of river larviciding on the target and non-target aquatic fauna - had been achieved . 3.9 Aerial prospection of southern Bioko A helicopter prosprection rvas conducted to the South of the island rvith the friendly assistence of MOBILE EQG , who supplied the aircraft and a crerv of two pilots free of charge. Several landings rvere made for river prospection. €) Date . Tirne: Area : Aircraft Pilots Prospection tearn Other passengers 24.02.01 10""- 14o" h at low tide Southem rivers between Riaba and Luba. Bell2l2 Helicopter S. Hannah , Canadian Helicopters , Base Manager B. Ingram , Canadian Helicopters , co-pilot R. Meyer, M. Wilson 4 Mobil Personnel l': t The flight rvas conducted along the southern coast line of the island frorn Riaba to Luba Alrnost all rivers which had been considered rvorth treating and rvhich had been coded rterc flou,ing. Besides , sonle very srnall rivers , rvhich had not been coded , \\Icre obseri,ed to have florv. Arnongst a total of approxirnatly 40 rivers rvere 4 rnajor basins : Ilady , Moaba , Osa and Ole. All lour basins arc rvide and o1rcn , including thcir tributaries , right up to thc uppcr lirnit of the planned aerial trcatmcnt. They have stcep gradtcnts, rcachtng the ( t500 m elevation line 7 km ( tlady, Moaba and Ole ) respectively 5 km ( Osa ) above their mouth. The four rivers consist of a continuation of rapids, falls and pools . They resemble the mountainous part of the Asukawkaw basin at the Ghana / Togo border. But they are larger and even more spectacular. [[ady, Moaba and Ole were flowing well , whergas the Osa was almost dry. l^andings were made at the mouth of the Moaba and the Ole . Access for the prospection of the Moaba was limited due to a water fall located just a few hundred metres above the mouth of the river. The gites below the fall were not suitable for breeding , being a tidal zone . Discharge of the Moaba was estimated at 20 - 30 m3/s.The Ole was flowing at 5 - l0 m3/s . Rocky gites continued right down to the outlet into the sea ( Plates S I- s16 ). All stages of S. damnosum were found less than 200 m upstream from the sea. With few exceptions larval supportsconsisted of fallen {eaves and twigs between the rocks. Population was dense and evenly spread throughout the gites. The smaller rivers are , of course , more overgrown . But due to the nature of the terrain - steep gradient and rocky vulcanous ground - enough openings exist to enable successful aerial larviciding. Treatment might, however, require more flight time than anticipated. The nature of the large rivers would even enable successful application of Bt. 4.0 OBSERVATIONS, RESULTS AND DISCUSSIONS The ground larviciding operations of the dry season 2001 served as preparatory activities for a combined aerial and ground-eradication programme on the island , planned for the coming dry season. Much information rvas gained about the particularity of rivers , the efficacity of the product, diffculties to be expected and the possibilities to tackle the problems. [,ocal authorities and the population tvere sensitizec- A relatively low carry of the product of 1-3 km was observed even in well flowing rivers and again less in streams with poor flow. The comimg eradication programme will have to take this into account in the planning and budgeting for larvicides and flight hours. An abundance of suitable larval supports exists and generally there is a wide spread distribution of S. damnosum in large rivers although breeding is not as dense as one would have expected under these conditions. Small streams usually bear poor populations, which might be due to frequent changes in discharge. Slorv breeding cycles and slow repopulation of suppo(s were observed , rvhich will be due to the relatively lorv prevaling water temperatures , ranging from l9 to 24" C .At altitudes around 300 m above sea level a reduction of S. damnosum populations and an increase of non-damnosum species was observed and at heights above 500 m no S. damnosum larvae rvere found any more. However, adult flies were even caught at B altitudes above 1000 m, although fly densities decreased with increasing altitudes( Reports R. Cheke, P. McCall, M. Wilson ). At most catching points aldult fly populations declined rapidly after the start of the treatment and in some locations even reduced to zero after only four weeks although no river system was treated in full . [n other places however, only little effect was observed. In general , flies seem to be less active than known from the populations in the OCP area. The mode of resurgence of the flies after termination of the treatment might give more interesting information ( Report M. Wilson ). Poor ground access existed along most rivers and many tributaries could not be reached at all. But there seems to exist sufficient access for aerial treatment , all the more as extensive deforestation during the last two years has opened the canopy in many places. Most of the badly needed larvicide and equipment did not arrive on time this season. Emergency alrangments enabled a successful continuation of the project under aggravating conditions. Simular problems however,during aerial eradication activities would jeopardise the success of the whole project. Future consignments should be sent more timely. Sufficient storage capacity now exists at the compound of the OMS Representation in Malabo. The southern part of the island is completely inaccessible from the gound . An aerial prospection was conducted and revealed that aerial larviciding would be feasible. 5.0 CONCLUSIONS AND RECOMMBNDATIONS Promising results were achieved although numerous problems were encountered and the ground larviciding activities were not terminated as planned. But the following conclusions can be drawn and recommendations be made: Eradication by ground larviciding alone is not possible , due to the limited access to the rivers. Aerial treatment combined with ground treatment assistance is considered to be a suitable method to carry out the work It is our conviction that - technically - the vector eradication in one single season is feasible. ll Temephos ( Abate 20EC ) has shown good efficacy and should be used as Iarvicide at a dose of 0,4 litre product/ m'/s discharge. iii. A new formulation of Bt should be used to complement temephos whereever possible , although the product could not be tested this year .[n any case the Bt-stock ,which only arrived at the end of this year 's treatment should be used next season . However, it has to be kept in mind , that the use of Bt will increase the helicopter flight hours. iv Under no circumstances should the solitary ground larviciding be repeated Due to inaccessibility most rivers can only be treated partially and a multitude of locations are exposed to sublethal doses after each treatment. This will almost certainly promt a rapid development of resistance. , € t- -tL' t. 9 lx v A fair amount of sensitization of the local authorities and population has been achieved this year. Generally, a very positive attitude can bc observed towards the project. But some new incidents this year showed that a fair amount of sensitization - particularly the security forces - still remains to be done before the use of a helicopter can even be considered. vi. Considering the amount of planning and preparation required to set up aerial operations and the limited time remaining, action should be taken immediately. It has to be kept in mind that the routine renewats of the OCP aerial contracts always required 18 months of preparation. This contract is more complicated and complex and only 8 months are remainning until the start of the next dry season. vii. The contractor should be notifed about the treatment plan and time schedule. A time-table for organisational and technical discussions should be established .A'pilot shouldbe selected and informed as soon as possible to enable him to be prepared. viii. The Equatorial Guinean Government, the NOTF and the OMS Representative should be informed about the project plan and the time schedule. Mobil EQG should be informed about the project, and our intention to use their hanger.A request should,be made if, and under what.conditions, we might use their aircraft for rescue in case of emergency. Hydrobiological tests should be scheduled in the south before the start of the treatment. This year again, numerous serious and unnecessary problems were encountered which jeopardizedthe whole project tfuough the destructive and incompetent behavior of the NOTF Coordinator. The project could only be conducted with numerous delays and adjustments and it was fortunate that no real goal had to be achieved. An aerial eradication programme , which attempts to eliminate the vector in one single four-months-lasting season is bound to fail, if the NOTF Coordinator remains in his present position. x. xi 10 TABLE 7- APOC VECTOR ELIMINATION PROJECTT BIOKO EQUATORIAL GUINEA WATER CONDTTION MONTH: February 2OO1 25.4 2' 7o 9o 130 127 11,4 L26 1.26 745 1-46 L42 97 93 93 8o a45 452 78 8S 9r 3O 18 z5 27 25 SECTION APPLIC POINT .1 ^5/,u{ oc pH Coudrrct. mS/s Matadero I.latadero Borabuope Ebuchu Bopebie Bopebl-e Setaeeta EoIa BaI.ekia Ruroa br. Mecaico Grands MusoIa Musola Eba Saba Boolo ch. Boba Boba Ocooco Builo Apu $,ampaCa RIVER Toco Toco Machuc Machuc Ru.ma Rrrma Grande BA 2O2 BA 2O2 cA 5O1 cA 600 cA 500 cA 7OO cA 800 cA 101 cA 101 o- o- AB 22O AB 22O AB 242 AB 227, AB 247 Ac 7Lo AC 7tO AC 711Ac ?tz AC 731 cc 472 Cc 472 cc 450 leo z5z 77 17A 50A4t 45 46A 49r 51A 5rs 54s 54c 95A 96A 97 99 100 101A lo2 105 105 1(}8 111 1.74 1 19A t24A t25 128 L50 t3L 162 201 1ro ot5 or1 otol ot5 ot5 or5 ot5 ot 1 o.2 o12 or1 o12 1ro 2t5 1to o15 or5 ? ot5 ot5 ot2 ot1 oto5 or 1 o to5 o,01 o. 05 or5 or1 24.6 2t 27 24.5 25.5 22.1 22.7 24.8 20-.6 21.7_ 24.l 26.2 24.O 24.t 19.7 18.g 25.4 21.5 23.7- 23.9 25.8 25.4 27.8 t 4 2 o 4 1 , 1 6 t 4 5 5 4 5 5 4 8 8 8 7.8 a a a 6.1 7.68.o 7.98., B. 8. B. 7. B. 8. B. 8. 7. 9. 1ta8. 8. 8. j) TABLE 2 APOC VECTOR ELIMINATION PROJECT, BIOKO EQUATORIAL GUINEA RIVER TREATMENT MONTH:febr.,/March o- River Section Application Point No. ly't" Treatment information Consul BA 1OO 1 NV il 2 NY Consul BA 101 3 or05 il 4 ot5 contar rinatec il 5 o.3 contar rinate< Consul BA 103 6 NY il 7 NV Matadero BA 2OO I NV il o NV il 10 NY il 11 NA il 12 o.1 7 t 7 1, 1 Matadero BA 201 13 2to 2o 2o 2o 2o 2o o Matadero .ib "BA2O2 L5 I 14 ' orZ NV 2 2 2 2 2 tl 15 NV ll 16 o, o1 ll 17 1ro 9 1o 1o 1o 1o Ericorico ll BA 3OO L7A 1B or) NV 5 5 5 Ericorico BA 301 19 ot5 2 2 , o 2 ot5 3 ) ) 5 1 tgb%ft$i$S"s" (BA%?.100EC* Tfr= no1r67; NA iot ,""1?.,0,"' r#= not u,1,?"0; uslonot suited Flatadero BA2oo 778 1r o 1o 1o 1o 1o 1oEricorico BA5o5 19A --o;1- 7 7 L - WEEK ll 20 -1- TABLE 2 (continued) APOC VECTOR ELIMINATION PROJECT, BIOKO EQUATORIAL GUINEA RIVER TREATMENT MONTH:Febr.,/March o1 River Section Application Pointr No. l,nt / " Treatment information B 1 Borabaabo BA 303 21 NV Iterile BA 304 22 Ivv Brabecho BA 305 23 NV Co BA 4OO 24 NV Co BA 401 25 or1 1- 1 t t 1Bolaboorla Co BA4o 1 25,^ 26 orol or1 7 Bobo BA 403 27 NV r 28 NV Borabuope CA 1OO 29 NF il 30 NF Bojo CA 2OO JoA 31 or1 NS 7 il 32 NF Eute CA 3OO 33 NS It 34 NF Socopetete CA 4OO 35 NS il JO NS ll 37 NF Ebuchu CA 5OO 3B NV ll 39 NF il 40 NV *epr €' {'i\.-, Legend:dosage (l/Abate 200EC). NF = no flow; NA = not accessible; NV = not visited ; NS=not suited. -2- tTABLE 2 (continued) APOC VECTOR ELIMINATION PROJECT, BIOKO EQUATORIAL GUINEA RIVER TREATMENT i MONTH:Febr./Marctr o1 oco o Oo Legend: dosage (l/Abate 200EC), NF = no flow, NA = not accessible, NV = nol visited i NS=nsf, suited -5- Treatment information WEEK River Section m5/" Application Poin No. 7 B 9 1o LL Ebuchu CA 501 41 orol il 42 NA NSBuchuala CA 502 43 Bopebie CA 600 44 NS rl 45 NS il 46 ot5 Bobiale CA 601 ltoA 47 ot2 NS Setaseta CA 7OO 4B NS il 49 NF Eola CA 8OO 49A 50 ot5 NS il 51 5re 5Z NF .----= Q.) NS-Pela CA 9OO ll il 53 NS Toco CA 101 54 NS Sopo ll cA 110 54L 55 NS NS CA 111 56 NS Laja CA 120 57 NF Bosua CA 130 5B NF Bolaescuba CA 140 59 NF Mmo CA 141 60 NF Balekia 578 or1 1'oco CAlo 1 548 o.2 5 5 5 TABLE Z (continued) APOC VECTOR ELIMINATION PROJECT, BIOKO EQUATORIAL GUINEA I RTVER TREATMENT MONTH: Febr./March o1 River Section Application Pointl No. I lm) /s Treatment information WEEK 7 I 9 1o 11 Suhu cA 150 61 NF CA 151 62 o. o5 L Bachila CA 152 63 NS Tapechique CA 160 64 NS m 65 NA Capo cA 170 66 NF ll 67 NA Buala CA 171 68 NF Toho BA 5OO 69 NF Cuo BA 501 70 NS Ebehe Ria - Ria BA 601 7oA 71 o.o5 o. o5 I : 1. Cope BA 7OO 72 NF Lopa Cope CA BA 172 7oo 72!t 73 o. o5 NA 1 1 1 1 Boo BA 801 74 NF Biru BA BO2 75 NA Ote BA 804 76 NS Kibaco CA 1BO 77 NS Uba BA 901 78 o.5 5 5 5+5 5 5 il 79 NA Legend: dosage(l/Abate200EC),NF=noflow; NA=notaccessible; NV=notvisited.NS=not suited e,} a li -4- I l APOC VECTOR ELIMINATION PROJECT, BIOKO EQUATORIAL GUINEA I TABLE 2 (continued) MONTH: Febr./March o1 a RIVER TREATMENT Legen 7 e (l/Abate 200EC), NF = no i NA = no( accessible: NV = not v 666 lNS=not wisited6 te Treatment information WEEK o River Section Apptication Pointl No. | ^5t" BB 103 BO NF BB 104 81 NS Batatale/lloto Eoihe/uoche Date BB107 82 NF Bitera.r/Ectrue cB 190 B3 NS Echue CB 191 B4 NA/NT Chue / Buba BB 110 85 NF Buba (Chue) BB 111 B6 NA,/Nr Buile BB 121 87 NF Nca AB 101 BB NF Sabo BB 130 89 oool Sabo BB 131 90 o. o5 t 7 L 1 1 tl 91 NA Uri BB 132 92 NF Basaca 88133 93 NF cB 200 94 NF CB 2oo 95 o.1 1 1 1 L!{achuchumua; ro CB 2oo 95A 96 o.1 o.1 L L 2 1 D 1. 2 1 2 7!1actruchurnua: Ruma Lo AB 220 9bA 97 o.2 1.o 2 1o 1o 2 1o 2 1o , 1o r 9B 1.o 1o 1o 1o 1o 1o 99 2.5 25 25 25 25 25 Grande AB 242 100 1.o 1o 1o 1o 1o 1o Ruma AB 22o looA o.5 c 6 7 U 9 11 ll ' TABLE z (continued) . APOC VECTOR ELIMINATION PROJECT, BIOKO EQUATORIAL GUINEA RTVER TREATMSNT MONTH: Febr./March o1 River Section Application Pointl No' l*r,- Treatment information WEEK .l A o 'ln 11 Ruma AB23O 101 5-o 5o 5o 5o 5o 5o Ruma branc Mecaico AB 221 1o1A 102 o.5 o.6 5 6 6 6 6 6 6 6 5 6 Grande AB 241 103 NA Grande/Goula AB 242,246 104 NA Calabo AB 243 105 NA Musola AC 710 106 o.7 3 4 5 5 5 n tl 1t9n o.5 ? i )lt 1olL 1oL ll ll 1,oZA 108 o.3 1o 1o rl 109 o.5 5 4 4 4 4 Eba AC711 110 o.5 ll 1 1 1 o-7 \ 4 4 4 4 112 o.5 ) 4 4 4 4 113 o.5 7 4 4 4 4 Saba AC 712 114 ct-2 2 2 2 2 2 r 115 o.2 2 2 2 2 2 Eba AC 7. 11 116 o.5 5 4 4 4 4 Musola AC7'20 117 L.5 75 1.5 2o 2o 2o Musola AC 740 118 2.o 2o 25 25 25 25 Boolo AC 731 119 o.5 6 1o 1o 1o 1o ll il 1 1gA 120 o.1 ^-6- - Lx5 6 tx5 'to tx, 1o 1x5 1o Lxj 1o Ruma darn 1o1B 5 Legend: dosage (l/Abate 200EC), NF = no B , ..1LJ oO flow: 5o 5o NA = not accessible; 5o 5o not visited l NS=not suited -6- 5oNV= m il ra 3TABLE Z (continued) APOC VECTOR ELIMINATION PROJECT, BIOKO EQUATORTAL GUINEA RIVER TREATMENT MONTH: Febr../I.tarch o1 River Section Application Poind No | #/, Treatment information WEEK 7 B 9 1o t! Boolo channe I 1 2 1 o.1 t 2 2 2 2 Boolo chann e1 122 _9- l O.1 NF NF Boolo ctrann Tu eI BC 1BO 7"22A 123 NF Boba cc 472 124 Oo1 L 1 L 7 1 ll tt t24A 125 o o05 oo1 1 L t 7 1 1 1 1 1 L i'lotamotel 126 NS Ndaa BC 170 127 NF 128 o.o5 t 1 1 L 7 cc 471 129 NA Ococo CC 460 130 o.o1 Builo Tibur ongs -Tiburones 1 3 1 o.ol L 1 L 7 t AD Boo ti2A NF AU UlU 'tJz NF It 133 NF lt 134 NS MusoIa AC 77o 135 2 -ct 2o 2o 2o 2o 2oMuso1a tri' Bisoco r.AC 75o AD BZt 735A 136 o.5 o.5 5 5 5 5 5 5 5 5 5 5 Edda ll AD 812 t36A 137 o.5 o.1 ) 2 5 2 3 o ) 2 3 o Matogi AD 815 138 o.6 6 B B B B LadalEaaa AD 816 139 NA 140x -7.5 2) o.J 75 1 75 3 t5) L5) L51 Legend: dosage (l/Abate 200EC), NF = no flow; NA = nol access Musola trib. - LjjB o.1 5 Ll55c o.1 NF , NV = not vrsited l NS=not l. Bisoco Lada trib. AD Bzt 7568 o.j 14oA o.4 ; -7- L 3 5 t ) C) 7 5 5 5 5 suited ll TABLE Z (continued) . APOC ""'O* ELIMINATION PROJECT, BIOKO EQUATORIAL GUINEA RtvERtReafUeruf i UOrufg.Febr./March o1 River Section Application [lin'[,r2" Treatment information .vEDK 71u19 1o 11 cD 471 141 O oO1 Barinco AD 924 1Ir1A 142.,: O.O1 ', o.2 2 7 1 t t Maloho ll AD 92o AD 95o A 143 o.1 NA NF il 144 o.4 4 4 4 4 4 Chike cD 472 145 o.1 1 1 Pade CD 473 146 o. o5 o.o1 Bichibi CD 474 147 OoOl Pututu cD 475 148 o. o5 NF Esaa/Rupe BD 191 149 Oo1 t t L t L Laric BD 193 150 o. o5 t L 7 t 1 il ll 15.D4 o. o5 1 7 1 1 L Bioco cD 476 152 o. o5 ope BD 2OO 153 NF Biala CD 480 154 o.o5 7 1.+L 1 1. 1 ll Toaca ll CD 490 154A 155 O.1 o-o1 I 1 L 7 1 Bialauchi cD 490 156 OoOl Co CD 5OO 157 o.o1 il 158 OoOl Legend:dosage(l/Abate200EC),NF=noflow; NA=notaccessible; NV=notvisitedlNS=not suite$. e) a-: -B- n ea TABLE 2 (continued) a APdC VECTOR ELIMINATION PROJECT, BIOKO EQUATORTAL GUINEA RIVER TREATMENT MONTH: Febr.,/March o1 Oo o Legend: dosage (l/Abate 200EC), NF = no flow; NA = not accessible; NV = not visited g NS=rrqf suited -9- Treatment information WEEK River Section m' "rl 5/" Application Poi No. 7 I 9 1o 11 Co CD 5oo 159 NF Nale CD 510 160 o.o1 Apu AD 102 1 6 1 o.4 5 6 5 6 162 o.5 6 6 6 6 It 163 NA Bosao BD 210 164 o.01 ll 165 NF Bota BD 212 166 o. o1 Bolaopi BD 220 167 o.2 , t ) ) 5 168 o.2 2 2 2 2 5 169 o-a \ 1 \ Bueljeba BD 221 170 o. o1 Abaa CD 521 171 o.ol L L 1 t L Lopesa AD 118 172 NA il 173 NF Nale AD 119 174 o.o1 Lue AD 116 175 NF 176 NA Tiburones AD 111 177 777 L B B Oo Oo 1o NA B B B B B B 1o 1o - il n TABLE Z (continued.) APOC VECTOR ELIMINATION PROJECT, BIOKO EQUATORIAL GUINEA RIVER TREATMENT MONTH: Febr./March o1 River Section Application Pointl No' I ) /s Treatment information WEEK o 1 Tiburones AD LTl. 178 o.B B B B B B It 179 1oo 1o 1o 1o 1o 1o Urabela/Sacriba AD 115 180 NV AD 115 181 O oO1 lt 182 Nr/ Dibeleo AD 114 183 NF 184 NV Mirupuru CD 530 185 Iw tl 186 NF 187 o. o5 o.o1 ll 188 o.4 4 4 4 4 4 Mopobill CD 540 189 o.1 L 2 2 2+2 2 Mopobill CD 541 190 o. o5 L L 1 7 t Copetua ll cD 542 lgoA 191 o. o5 NS 1. 1 1 t 1 Balabaril pec es il CD il3 19 rn,192 g. o5o.o1 2 2 2 2 il 193 NF Balabari(Peces l CD 544 194 NF Bosecabosechi BD 230 195 NV ll 196 NF ll 197 NF e f't\-l I Legend: dosage (l/Abate 200EC), NF = no flow: NA = not accessible; NV = not vrsrted ; NS=not suited - 1o- il L'l tTABLE 2 a APOC VECTOR ELIMINATION PROJECT. BIOKO EQUATORIAL GUINEA RIVER TREATMENT , MONTH: Febr../Marctr o1 Legend: dosage (l/Abato 2O0EC), NF = no flow; NA = not accessibte: NV = not visited i NS=n6lguitod Treatment lnformatlon gEEK Rlver Section Applicatlon /a, Poi N" 7 B 9 1o 11 BD 231 198 Ao2 L q t 1 L Sa BO 232 199 NV n 200 .1 1 L I t 14trpaca c el BD 232 2ooA 201 o.1 oo1 1+1 1+1 1+1 1+1 + 1+1 + Bolola BD 233 202 Nv 203 NF lt 204 OoOl ll 205 NF Timbabe AD 121 206 Nrr il 207 OrO 1 t 1 PoIIu lon Timbabe AD 122 208 o.05 1, 1 1 1 OoO Timbabe AD 123 209 OrOl Bioto AD 129 210 NV at 211 NII rl 212 O.1 NF il 213 OoOl - 11- to t L.J a a) t BIOI(O North I)Late L C0 BA {Olr potn{ 2,5 Dlscharga orl m'/s Plate 2 CO llA lt0t, Poin ili;rcha.rg$ s r oSrft t l s6 ls ./{ [- tir, .. 'q:1 !1 \ f ./t'F ''.,]q s {t { , tt a n IOK() East, a Flate 5 SUFIL: CA 151, PoiDischarge o*oi ET1fi- ir /s Lil ate Il t!ilA l}A 9(} t [,oin lli-scharg* o, l nr ari /* t .) If"'" - {BIOKO gf,*ST Plate 5 RtrML et Ba]'acha.All 22O Point 97(o1d) Disclrarge lro st-,/s Plate 6 I'tEcAICo (siloco) lagzl Point LoE Disctrarge o r6 *i / = t *,'L * q" ,i a .r..G- '.a *- 4..i .\ , t ir .:5 {. al I I ! d S.". **. t .! .& Fii a BIOKOEAST t Point 99 (o1d) - jr r) m /s !)oin t 99 ( new ) - \,:} m- /s t ,'{r. :J'h- * *!{ t g;:+**.t? ooi*' , ",*=*' ti r t' tj! ,. l),1( 'tlt' lfJ-- -r *a*,! i .-i&o1' rS,,lL. ,l-'*:! .61 vs f *. *l ,i q-' *v ,BIOIiOEAST l:Iate I GRTNDE AB Dischar.{e Z4e, Point, 1oo 1ro m51s ?p l'l.ate 1o l{tj}'[A,/Gtt**\t]f, ConfluexLce Au 22A/Ats 2,42 Uischar*ee ir5 !rt],/s , * II i\ \ t- ; ir,, i f* PI ate 11 RU!44 Sam Point lO1 B Disetrarge Fro m-l/a Plate 12 RUI"{A AB 21o-troint tOt Discharge 5rs BIOKCEAST 1,E /, !a o a BIOKO Plate 1,3 tlIIMA Branch Perint 1O1 t Discharge o i)l.al-r: 14 MUSOLA AC Poi-nt 1O6 Discharge ,5 ^31 It l ',l " qr t B {v ,ffi * ( : ,,it' ' ',,i: '' it: '"1 n:f, *o-,* '{. arr . ,i 1 Ir t f ,. tri t t* 3 /s \ {BIOIiOWEST Irlato 15 F:nA AC ?t l rPoint 1t 1" tl'j.setr{tr$s o-5 *5./* Jl1ate 16 MUSOLA AC ?g0r Point t1? Dleclearge 1r5 m)/s *; *ll ''i , i*. i I \ '* ,f .t I BIOKO WEST Platm 1? BOOLO AC ?5t PoLnt tAO DJ.eeh*rge o16 nr5,/u P}ate 1B UCA, ACTAJ Discharge lro ,n3/s j*: ! ,:, \ ri "S j i;* - '.r4 .. ,BIOIiO ldEs? ,Pl-ate 19 MUSOL*' AC 73O Point L35 Oischa-rgo B1s E '/s ''ri 11U Discharge 2rFPlate ZO MUSOLA AC 74O Point tri -1 /s I -'"F'. ;F * ^rT *'* a' t{rxt' t :t ;..d tri t EIOKO !{EST P1ate ZL LARIC 8D195 Foint I-5OA Discharge oro5 ^1|u Plate 22 IIIALA CD lr8o Foint l5t{A l}ischarge or 1 m t) /* s:"-'^ frryrx tl { :7 Wt t' f ,I ti '.rl * :' iB + s 1': I BIOKO IJEST P1ate 23 APU AD !O2 Point 161 Discharge o, 4 *1/* Irlate ?tt l"lALAOI'l 8D220 Point 167 Dieeharge or2 m ! <- t- a t t I d -::s
e{. BIOKO SOUTHCOTST Pl"ato S 1: Mouth of l{0A$* tC I*4O o Flat,e S 2t F,louth of MOARA l,C ttrO Me.l+#'.dY ' rir t'' 'r.,; t i *''' ' -.+ ". t+k i{ BIOKO SOUTH COAST Pl.ate S 5lFall-c of ].arer t-rOABf AC ltr+0 Plate 5 lrr I.TOABA AC {4O ,:P - Ii" rdgri * {!E ,t{; - . -F- f i* Jq {!fi jlY { ,! ,i '1 ;.," '''';iEi l:- r.. , ,,..,,i '?.d BroEo soutH cQfisr ,Sl"ats $5 tFellr of LOiRrt(l.toaba trihutary) a o FLate 56g MotBA AC &5O f ') :',, .1, Pl*te S7: l,loABA f,C IiSO Flate S8: I.IOABA confluence AC42O/42J r*ith l.:C45O BIOKO 5OUTH COAST ,BIOEOSO{ITTICOTST Ptate $9t NS&B* lC {rg0r BISS€fl IlC &e5 Pla-te S1O: MOAET iC IraO, BfSOCO AC 4Zj .#4: I d 'i {" i ,*. { l- i .l;Bi'r.l'r-; .t L BIONOSOUTHCOAST a 'Plate 5 11 Muoth of OLE AC 6trO Plate S 12 Mouth of OLE AC 6{O a .'j,. ;" ! at a a O o BIOKOSOUTHCOfrST Plate $ 1,"5 oLE rc 6lo Plate S 1{ OLE AC 6AO a f I tr t i Plate S 15 oLE AC 6eO Confluence AC 6lO,/ec 6 t I J Plate S 16 oLE AC 52o, ConfLuence AC 6to/tc 6rf a I}IOKO SOUTIICOAST d ,f:r. ;.., i n:, - ,a!" lr t,t. t1