The Residual Efficacy of SumiShield™ 50WG and K-Othrine® WG250 IRS Formulations Applied to Different Building Materials Against Anopheles and Aedes Mosquitoes

Insecticides with novel modes of action are required to complement the pyrethroids currently relied upon for controlling malaria vectors. One example of this is the neonicotinoid clothianidin, which is found in SumiShield™ 50WG used in indoor residual spraying (IRS). In a preliminary experiment, mortality in insecticide susceptible and resistant An. gambiae adults exposed to SumiShield™ 50WG-treated filter papers reached 80% by 3-days post-exposure and 100% by 6-days post-exposure. Next, cement, wood, and mud tiles were treated with SumiShield™ 50WG or K-Othrine® WG250 (deltamethrin IRS formulation) and insecticide resistant and susceptible Anopheles and Aedes were exposed to these surfaces periodically for up to 18-months. Pyrethroid resistant Cx. quinquefasciatus were also exposed at 9 months. Between exposures tiles were stored in heat and relative humidity conditions reflecting those found in the field. On these surfaces, SumiShield™ 50WG was effective at killing both susceptible and resistant An. gambiae for 18 months post-treatment, while mortality amongst the resistant strains when exposed to deltamethrin (K-Othrine® WG250) IRS was not above that of the negative control. Greater efficacy of SumiShield™ 50WG was also demonstrated against insecticide resistant strains of An. funestus compared to deltamethrin, though the potency was lower when compared with An. gambiae. In general, a higher efficacy of SumiShield™ 50WG was observed on cement and mud compared to wood. SumiShield™ 50WG demonstrated poor residual activity against Aedes aegypti and Culex quinquefasciatus. Overall, the results suggest SumiShield™ 50WG is well suited for malaria control.

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Insecticide resistance status of malaria vectors Anopheles gambiae (s.l.) of southwest Burkina Faso and residual efficacy of indoor residual spraying with microencapsulated pirimiphos-methyl insecticide

Parasites & Vectors ◽

10.1186/s13071-020-04563-8 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Dieudonné Diloma Soma ◽

Barnabas Zogo ◽

Domonbabele François de Sales Hien ◽

Aristide Sawdetuo Hien ◽

Didier Alexandre Kaboré ◽

...

Keyword(s):

Insecticide Resistance ◽

Burkina Faso ◽

Anopheles Gambiae ◽

Local Population ◽

Residual Activity ◽

Indoor Residual Spraying ◽

Susceptible Strain ◽

Malaria Vectors ◽

Pirimiphos Methyl ◽

Residual Efficacy

Abstract Background The rapid spread of insecticide resistance in malaria vectors and the rebound in malaria cases observed recently in some endemic areas underscore the urgent need to evaluate and deploy new effective control interventions. A randomized control trial (RCT) was conducted with the aim to investigate the benefit of deploying complementary strategies, including indoor residual spraying (IRS) with pirimiphos-methyl in addition to long-lasting insecticidal nets (LLINs) in Diébougou, southwest Burkina Faso. Methods We measured the susceptibility of the Anopheles gambiae (s.l.) population from Diébougou to conventional insecticides. We further monitored the efficacy and residual activity of pirimiphos-methyl on both cement and mud walls using a laboratory susceptible strain (Kisumu) and the local An. gambiae (s.l.) population. Results An. gambiae (s.l.) from Diébougou was resistant to DDT, pyrethroids (deltamethrin, permethrin and alphacypermethrin) and bendiocarb but showed susceptibility to organophosphates (pirimiphos-methyl and chlorpyrimiphos-methyl). A mixed-effect generalized linear model predicted that pirimiphos-methyl applied on cement or mud walls was effective for 210 days against the laboratory susceptible strain and 247 days against the local population. The residual efficacy of pirimiphos-methyl against the local population on walls made of mud was similar to that of cement (OR = 0.792, [0.55–1.12], Tukey’s test p-value = 0.19). Conclusions If data on malaria transmission and malaria cases (as measured trough the RCT) are consistent with data on residual activity of pirimiphos-methyl regardless of the type of wall, one round of IRS with pirimiphos-methyl would have the potential to control malaria in a context of multi-resistant An. gambiae (s.l.) for at least 7 months.

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Effect of wall type, delayed mortality and mosquito age on the residual efficacy of a clothianidin-based indoor residual spray formulation (SumiShield™ 50WG) in southern Mozambique

PLoS ONE ◽

10.1371/journal.pone.0248604 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0248604

Author(s):

Helena Marti-Soler ◽

Mara Máquina ◽

Mercy Opiyo ◽

Celso Alafo ◽

Ellie Sherrard-Smith ◽

...

Keyword(s):

Vector Control ◽

Disease Transmission ◽

Indoor Residual Spraying ◽

World Health ◽

Malaria Vector Control ◽

Mosquito Vector ◽

Post Exposure ◽

Mosquito Mortality ◽

Residual Efficacy ◽

Delayed Mortality

Indoor residual spraying (IRS) is one of the main malaria vector control strategies in Mozambique alongside the distribution of insecticide treated nets. As part of the national insecticide resistance management strategy, Mozambique introduced SumiShield™ 50WG, a third generation IRS product, in 2018. Its residual efficacy was assessed in southern Mozambique during the 2018–2019 malaria season. Using a susceptible Anopheles arabiensis strain, residual efficacy was assessed on two different wall surfaces, cement and mud-plastered walls, using standard WHO (World Health Organization) cone bioassay tests at three different heights. Female mosquitoes of two age groups (2–5 and 13–26 day old) were exposed for 30 minutes, after which mortality was observed 24h, 48h, 72h, and 96h and 120h post-exposure to assess (delayed) mortality. Lethal times (LT) 90, LT50 and LT10 were estimated using Bayesian models. Mortality 24h post exposure was consistently below 80%, the current WHO threshold value for effective IRS, in both young and old mosquitoes, regardless of wall surface type. Considering delayed mortality, residual efficacies (mosquito mortality equal or greater than 80%) ranged from 1.5 to ≥12.5 months, with the duration depending on mortality time post exposure, wall type and mosquito age. Looking at mortality 72h after exposure, residual efficacy was between 6.5 and 9.5 months, depending on wall type and mosquito age. The LT50 and LT10 (i.e. 90% of the mosquitoes survive exposure to the insecticides) values were consistently higher for older mosquitoes (except for LT10 values for 48h and 72h post-exposure mortality) and ranged from 0.9 to 5.8 months and 0.2 to 7.8 months for LT50 and LT10, respectively. The present study highlights the need for assessing mosquito mortality beyond the currently recommended 24h post exposure. Failure to do so may lead to underestimation of the residual efficacy of IRS products, as delayed mortality will lead to a further reduction in mosquito vector populations and potentially negatively impact disease transmission. Monitoring residual efficacy on relevant wall surfaces, including old mosquitoes that are ultimately responsible for malaria transmission, and assessing delayed mortalities are critical to provide accurate and actionable data to guide vector control programmes.

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Residual Efficacy of Fludora® Fusion Against Anopheles Arabiensis in Simple Huts in Ethiopia

10.21203/rs.3.rs-236028/v1 ◽

2021 ◽

Author(s):

Abebe Animut ◽

Sebastian Horstmann

Keyword(s):

Mortality Rate ◽

Anopheles Arabiensis ◽

Post Treatment ◽

Holding Time ◽

Malaria Vectors ◽

Post Exposure ◽

Interior Wall ◽

Residual Efficacy

Abstract Emergence and spread of malaria vectors resistant to the available insecticides required a new and efficacious insecticide. Residual efficacy of Fludora® Fusion was evaluated against insecticide susceptible Anopheles arabiensis in ten circular huts similar to the residential huts. Fludora® Fusion WP-SB 562.5, FICAM WP80 and Clothianidin WG70 were sprayed, by experienced technician, on interior wall surfaces: paint, dung, smooth mud, and rough mud. WHO cone bioassays were carried out a month after spraying and thereafter on monthly intervals for 12 months. Knockdown was recorded at 60 minutes and mortality at 24 hours, 48 hours and 72 hours holding time post-exposure. Fludora Fusion induced 100% An. arabiensis mortality during the first four months post-treated on all surface types at 24 hours holding time post-exposure. Its activity remained over 80% from the fifth to the twelfth month post-treated on the surfaces with the exception of two assessment points, at seventh month and eleventh month, on paint and smooth mud surfaces. FICAM induced 100% mortality rate during the first 4 months and 92% mortality during the fifth month post-treatment on painted surfaces. Its activity was over 96% mortality 1-month post-treatment on smooth mud and rough mud surfaces and 92% mortality 2-month post-treatment on dung surfaces. Clothianidin caused 89% and 86% mortality 1-month post-treatment on smooth mud and rough mud surfaces. Fludora Fusion can be used as alternative indoor residual insecticide spraying against An. arabiensis in Ethiopia. However, the insecticide shall also be tested in residential houses prior to employing at a larger scale.

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Effect of wall type, delayed mortality and mosquito age on the residual efficacy of a clothianidin-based indoor residual spray formulation (SumiShield™ 50WG) in southern Mozambique

10.1101/2021.03.03.433723 ◽

2021 ◽

Author(s):

Helena Marti-Soler ◽

Mara Maquina ◽

Mercy Opiyo ◽

Celso Alafo ◽

Ellie Sherrard-Smith ◽

...

Keyword(s):

Vector Control ◽

Disease Transmission ◽

Indoor Residual Spraying ◽

World Health ◽

Malaria Vector Control ◽

Mosquito Vector ◽

Post Exposure ◽

Mosquito Mortality ◽

Residual Efficacy ◽

Delayed Mortality

AbstractBackgroundIndoor residual spraying (IRS) is one of the main malaria vector control strategies in Mozambique alongside the distribution of insecticide treated nets. As part of the national insecticide resistance management strategy, Mozambique introduced SumiShield™ 50WG, a third generation IRS product, in 2018. Its residual efficacy was assessed in southern Mozambique during the 2018-2019 malaria season.MethodsTwo different wall surfaces, cement and mud-plastered surfaces, daily mosquito mortality up to 120 hours post-exposure, and older mosquitoes (13-26d old) were included in standard WHO (World Health Organization) cone bioassay tests. Lethal times (LT) 90, LT50 and LT10 were estimated using Bayesian models.ResultsMortality 24h post exposure was consistently below 80%, the current WHO threshold value for effective IRS, in both young and old mosquitoes, regardless of wall surface type. Considering delayed mortality, residual efficacies (mosquito mortality equal or greater than 80%) ranged from 1 to ≥12 months, with the duration depending on mortality time post exposure, wall type and mosquito age. Looking at mortality 72h after exposure, residual efficacy was between 6 and 9 months, depending on wall type and mosquito age. Mortality of older mosquitoes was significantly higher on mud-surfaces compared to cemented-surfaces 24h post exposure, but this difference was not significant for the delayed mortalities. The LT50 and LT10 (i.e. 90% of the mosquitoes survive exposure to the insecticides) values were consistently higher for older mosquitoes using the 24h post-exposure observations and ranged from 0.2 to 5.7 months and 0.2 to 7.2 months for LT50 and LT10, respectively.ConclusionsThe present study highlights the need for assessing mosquito mortality beyond the currently recommended 24h post exposure. Failure to do so may lead to underestimation of the residual efficacy of IRS products, as delayed mortality will lead to a further reduction in mosquito vector populations and potentially negatively impact disease transmission. Monitoring residual efficacy on relevant wall surfaces, including old mosquitoes that are ultimately responsible for malaria transmission, and assessing delayed mortalities are critical to provide accurate and actionable data to guide vector control programmes.

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Efficacy of indoor residual spraying with broflanilide (TENEBENAL), a novel meta-diamide insecticide, against pyrethroid-resistant anopheline vectors in northern Tanzania: An experimental hut trial

PLoS ONE ◽

10.1371/journal.pone.0248026 ◽

2021 ◽

Vol 16 (3) ◽

pp. e0248026

Author(s):

Janneke Snetselaar ◽

Mark W. Rowland ◽

Baltazari J. Manunda ◽

Ezekia M. Kisengwa ◽

Graham J. Small ◽

...

Keyword(s):

Residual Activity ◽

Indoor Residual Spraying ◽

Concrete Surface ◽

Blood Feeding ◽

Cross Resistance ◽

Feeding Inhibition ◽

Experimental Hut ◽

Northern Tanzania ◽

Residual Efficacy ◽

Diamide Insecticide

Novel chemistry for vector control is urgently needed to counter insecticide resistance in mosquitoes. Here a new meta-diamide insecticide, broflanilide (TENEBENALTM), was evaluated in East African experimental huts in Moshi, northern Tanzania. Two consecutive experimental hut trials with broflanilide 50WP were conducted; the first evaluating the efficacy of three concentrations, 50 mg/m2, 100 mg/m2, and 200 mg/m2 using a prototype formulation, and the second trial evaluating an improved formulation. The IRS treatments were applied on both mud and concrete surfaces and efficacy was monitored over time. The mortality, blood-feeding inhibition and exiting behaviour of free-flying wild mosquitoes was compared between treatment arms. Additionally, cone assays with pyrethroid-susceptible and resistant mosquito strains were conducted in the huts to determine residual efficacy. The first trial showed a dosage-mortality response of the prototype formulation and 3–8 months of residual activity, with longer activity on concrete than mud. The second trial with an improved formulation showed prolonged residual efficacy of the 100 mg/m2 concentration to 5–6 months on mud, and mosquito mortality on the concrete surface ranged between 94–100% for the full duration of the trial. In both trials, results with free-flying, wild Anopheles arabiensis echoed the mortality trend shown in cone assays, with the highest dose inducing the highest mortality and the improved formulation showing increased mortality rates. No blood-feeding inhibition or insecticide-induced exiting effects were observed with broflanilide. Broflanilide 50WP was effective against both susceptible and pyrethroid-resistant mosquito strains, demonstrating an absence of cross resistance between broflanilide and pyrethroids. The improved formulation, which has now been branded VECTRONTM T500, resulted in a prolonged residual efficacy. These results indicate the potential of this insecticide as an addition to the arsenal of IRS products needed to maintain both control of malaria and resistance management of malaria-transmitting mosquitoes.

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Laboratory and field evaluation of MAÏA®, an ointment containing N,N-diethyl-3-methylbenzamide (DEET) against mosquitoes in Burkina Faso

Malaria Journal ◽

10.1186/s12936-021-03755-6 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Alphonse Traoré ◽

Gérard Niyondiko ◽

Antoine Sanou ◽

Franck Langevin ◽

N’Falé Sagnon ◽

...

Keyword(s):

Burkina Faso ◽

Laboratory Tests ◽

Mosquito Species ◽

Anopheles Funestus ◽

Indoor Residual Spraying ◽

Negative Control ◽

Malaria Vectors ◽

Malaria Vector Control ◽

Insecticide Treated Nets ◽

H 30

Abstract Background Malaria vector control relies upon the use of insecticide-treated nets and indoor residual spraying. However, as the emergency of insecticide resistance in malaria vectors grows, the effectiveness of these measures could be limited. Alternative tools are needed. In this context, repellents can play an important role against exophagic and exophilic mosquitoes. This study evaluated the efficacy of MAÏA®, a novel repellent ointment, in laboratory and field conditions in Burkina Faso. Methods For laboratory and field assessment, 20 volunteers were enrolled and trained for nocturnal collection of mosquitoes using human landing catches (HLC). In the laboratory tests, 2 mg/sq cm of treatment (either MAIA® or 20 % DEET) were used to assess median complete protection time (CPT) against two species: Anopheles gambiae and Aedes aegypti, following WHO guidelines. For both species, two strains consisting of susceptible and local strains were used. The susceptible strains were Kisumu and Bora Bora for An. gambiae and Ae. aegypti, respectively. For the field test, the median CPT of MAÏA® was compared to that of a negative (70 % ethanol) and positive (20 % DEET) after carrying out HLCs in rural Burkina Faso in both indoor and outdoor settings. Results Laboratory tests showed median Kaplan-Meier CPT of 6 h 30 min for An. gambiae (Kisumu), 5 h 30 min for An. gambiae (Goden, local strain), and 4 h for Ae. aegypti for both the local and sensitive strain. These laboratory results suggest that MAÏA® is a good repellent against the three mosquito species. During these field tests, a total of 3979 mosquitoes were caught. In this population, anophelines represented 98.5 %, with culicines (Aedes) making up the remaining 1.5 %. Among anopheline mosquitoes, 95 % belonged to the An. gambiae complex, followed by Anopheles funestus and Anopheles pharoensis. The median CPT of 20 % DEET and MAÏA® were similar (8 h) and much longer than that of the negative control (2 h). Conclusions Results from the present studies showed that MAÏA® offers high protection against anophelines biting indoors and outdoors and could play an important role in malaria prevention in Africa.

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Insecticide resistance status of malaria vectors Anopheles gambiae s.l of southwest Burkina Faso and residual efficacy of indoor residual spraying with microencapsulated pirimiphos-methyl insecticide

10.1101/2020.07.13.200865 ◽

2020 ◽

Author(s):

Dieudonné D. Soma ◽

Barnabas M. Zogo ◽

François D. Hien ◽

Aristide S. Hien ◽

Didier P.A. Kaboré ◽

...

Keyword(s):

Insecticide Resistance ◽

Burkina Faso ◽

Anopheles Gambiae ◽

Local Population ◽

Indoor Residual Spraying ◽

Susceptible Strain ◽

Malaria Vectors ◽

Pirimiphos Methyl ◽

Anopheles Gambiae S.L ◽

Residual Efficacy

AbstractThe rapid spread of insecticide resistance in malaria vectors and the rebound in malaria cases observed recently in some endemic areas underscore the urgent need to evaluate and deploy new effective control interventions. A randomized control trial was conducted with the aim to investigate the benefit of deploying complementary strategies, including indoor residual spraying (IRS) with pirimiphos-methyl, in addition to long-lasting insecticidal nets (LLINs) in Diébougou, southwest Burkina Faso. We measured the susceptibility of Anopheles gambiae s.l. population from Diébougou to conventional insecticides. We further monitored the efficacy and residual activity of pirimiphos-methyl on both cement and mud walls using a laboratory susceptible strain (Kisumu) and the local An. gambiae s.l. population. An. Gambiae s.l. from Diébougou was resistant to pyrethroids (deltamethrin, permethrin and alphacypermethrin) and bendiocarb but showed susceptibility to organophosphates (pirimiphos-methyl and chlorpyrimiphos-methyl). A mixed-effect generalized linear model predicted that pirimiphos-methyl applied on cement or mud walls was effective for 210 days against the laboratory susceptible strain and 247 days against the local population. The residual efficacy of pirimiphos-methyl against the local population on walls made of mud was similar to that of cement (OR=0.792, [0.55-1.12], Tukey’s test p-value =0.19). This study showed that one round of IRS with pirimiphos-methyl CS has the potential to control the multi-resistant An. gambiae s.l. population from Southwest Burkina Faso for at least 7 months, regardless of the type of wall.

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The Efficacy of Vectron 20 WP, Etofenprox, for Indoor Residual Spraying in Areas of High Vector Resistance to Pyrethroids and Organochlorines in Zambia

ISRN Preventive Medicine ◽

10.5402/2013/371934 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Emmanuel Chanda ◽

Alister Kandyata ◽

Javan Chanda ◽

Faustina N. Phiri ◽

Lucy Muzia ◽

...

Keyword(s):

Insecticide Resistance ◽

World Health Organization ◽

Indoor Residual Spraying ◽

Control Programme ◽

World Health ◽

Malaria Vectors ◽

Insecticide Treated Nets ◽

Lambda Cyhalothrin ◽

Residual Efficacy ◽

Health Organization

The selection of insecticide resistance in malaria vectors has the potential to compromise any insecticide-based vector control programme. To ensure that the insecticides used for indoor residual spraying and insecticide-treated nets in Zambia remain effective and their choice is evidence based, insecticide resistance surveillance and monitoring are essential. This study assessed and compared the residual efficacy of etofenprox (Vectron 20 WP), an ether pyrethroid, at 0.1 g/m2 with pyrethroids: bifenthrin (Bistar 10 WP) and lambda-cyhalothrin (Icon 10 CS) at 25 mg/m2 for indoor residual spraying. We also assessed the resistance status of etofenprox to local malaria vectors, An. funestus s.s and An. gambiae s.s, using World Health Organization standard protocols. The residual efficacy of Vectron 20 WP on cement, rendered walls of houses lasted for four months with 100% mortality. By the eighth month, the killing effect had reduced to 73.8% compared to 63.3% for bifenthrin and 77.0% for lambda-cyhalothrin. Susceptibility tests using standard World Health Organization assays on An. gambiae s.s showed susceptibility to etofenprox (0.1%) but some resistance was detected to Anopheles funestus s.s. The product is recommended as an ideal insecticide for indoor residual spraying for malaria control in Zambia as part of a resistance management programme in selected areas of the country.

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Increased Biting Rate of Insecticide-Resistant Culex Mosquitoes and Community Adherence to IRS for Malaria Control in Urban Malabo, Bioko Island, Equatorial Guinea

Journal of Medical Entomology ◽

10.1093/jme/tjz025 ◽

2019 ◽

Vol 56 (4) ◽

pp. 1071-1077 ◽

Cited By ~ 5

Author(s):

Godwin Fuseini ◽

Raul Ncogo Nguema ◽

Wonder P Phiri ◽

Olivier Tresor Donfack ◽

Carlos Cortes ◽

...

Keyword(s):

Insecticide Resistance ◽

Residual Activity ◽

Indoor Residual Spraying ◽

Potential Effect ◽

Malaria Vectors ◽

Organophosphate Insecticide ◽

Bioko Island ◽

Anopheles Mosquitoes ◽

Biting Rate ◽

Community Protection

Abstract Sustaining high levels of indoor residual spraying (IRS) coverage (≥85%) for community protection against malaria remains a challenge for IRS campaigns. We examined biting rates and insecticide resistance in Culex species and Anopheles gambiae s.l., and their potential effect on community adherence to IRS. The average IRS coverage in urban Malabo between 2015 and 2017 remained at 80%. Culex biting rate increased 6.0-fold (P < 0.001) between 2014 and 2017, reaching 8.08 bites per person per night, whereas that of An. gambiae s.l. remained steady at around 0.68. Although An. gambiae s.l. was susceptible to carbamates and organophosphates insecticides, Culex spp. were phenotypically resistant to all four main classes of WHO-recommended IRS insecticides. Similarly, the residual activity of the organophosphate insecticide used since 2017, ACTELLIC 300CS, was 8 mo for An. gambiae s.l., but was almost absent against Culex for 2 mo post-spray. A survey conducted in 2018 within urban Malabo indicated that 77.0% of respondents related IRS as means of protection against mosquito bites, but only 3.2% knew that only Anopheles mosquitoes transmit malaria. Therefore, the increasing biting rates of culicines in urban Malabo, and their resistance to all IRS insecticides, is raising concern that a growing number of people may refuse to participate in IRS as result of its perceived failure in controlling mosquitoes. Although this is not yet the case on Bioko Island, communication strategies need refining to sensitize communities about the effectiveness of IRS in controlling malaria vectors in the midst of insecticide resistance in nonmalaria vector mosquitoes.

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Laboratory and field evaluation of MAÏA®, an ointment containing N, N-Diethyl-3-methylbenzamide (DEET) against mosquitoes in Burkina Faso

10.21203/rs.3.rs-58726/v1 ◽

2020 ◽

Author(s):

Alphonse Traore ◽

Gérard Niyondiko ◽

Antoine Sanou ◽

Franck Langevin ◽

N'falé Sagnon ◽

...

Keyword(s):

Aedes Aegypti ◽

Burkina Faso ◽

Anopheles Gambiae ◽

Field Test ◽

Indoor Residual Spraying ◽

Negative Control ◽

Malaria Vectors ◽

Complete Protection ◽

Human Landing ◽

Indoor And Outdoor

Abstract BackgroundMalaria vector control relies upon the use of insecticide treated nets and the Indoor Residual Spraying. However, as the emergency of insecticide resistance in malaria vectors grows, the effectiveness of these measures could be limited. Thus, alternative tools are needed. In this context, repellents can play an important role against exophagic and exophilic mosquitoes. This study evaluated the efficacy of MAÏA® , a novel repellent ointment, in laboratory and field conditions in Burkina Faso.For the Laboratory and field assessment, twenty volunteers were enrolled and trained for nocturnal collection of mosquitoes using Human Landing Catches (HLC).MethodsIn the laboratory tests, 2 mg / cm2 of treatments (either the MAIA® or the 20% DEET) were used to assess median Complete Protection (CPT) against two species that includes Anopheles gambiae and Aedes aegypti following the WHO guidelines. For both species two strains consisting of susceptible and local strains were used. The susceptible strains were Kisumu and Bora Bora respectively for Anopheles gambiae and Aedes aegypti. For the field test, the median CPT of the MAIA was compared to that of a negative (70% Ethanol) and positive (20% DEET) after carrying out human landing catches in rural Burkina Faso in both indoor and outdoor settings. ResultsLaboratory tests showed median Kaplan–Meier Complete Protection Times (CPT) of 6 hours 30 minutes for Anopheles gambiae (Kisumu), of 5 hours 30 minutes for Anopheles gambiae (Goden, local strain) and of 4 hours for Aedes aegypti for both the local and sensitive strain. Thus, these laboratory results suggest MAÏA® is a good repellent against the three mosquito species. Field tests showed that median CPT of 20% DEET and MAÏA® were similar (8 hours) and longer than that of the negative control (2 hours).During these field test, in the field a total of 3,979 mosquitoes were caught. In this population, Anopheline represented 98.5% and the culicine (Aedes) making up the remaining 1.5%. Among anopheline mosquitoes, 95% belonged to Anopheles gambiae complex, followed by Anopheles funestus, and Anopheles pharoensis. The median CPT of 20% DEET and MAÏA® were similar (8 hours) and longer than that of the negative control (2 hours).ConclusionResults from the present studies showed that MAÏA® offers high protection against Anophelines biting indoor and outdoor and could play an important role in malaria control in Africa.

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