Sensibilité des Populations D’Aedes Aegypti des Zones Héveicoles de Dabou (Sud de la Côte d’Ivoire) aux Organophosphorés, aux Pyréthrinoïdes et au Bacillus Thuringiensis Israelensis - Issouf, Traore; Ibrahima, Coulibaly Zanakoungo; Lucien, Konan Yao; Bernard, Allali Kouadio; Ahoua, Yapi; Dosso, Mireille (European Scientific Journal, ESJ, 2022)
Lâ€™expansion de lâ€™hÃ©vÃ©aculture entraine une forte modification de lâ€™environnement en CÃ´te dâ€™Ivoire. Aussi, plusieurs Ã©pidÃ©mies de dengue et de fiÃ¨vre jaune dues Aedes aegypti ont rÃ©cemment Ã©tÃ© observÃ©es en CÃ´te dâ€™Ivoire. Le profil de sensibilitÃ© aux insecticides dâ€™Aedes aegypti dans ces zones dâ€™agriculture de masse nÃ©cessitant une main dâ€™Å“uvre importante est mal connu. Cette Ã©tude a Ã©tabli le profil de sensibilitÃ© dâ€™Aedes aegypti dans les zones de cultures dâ€™hÃ©vÃ©a de Dabou afin de mieux planifier les mesures de lutte contre le vecteur majeur des dâ€™arbovirus. Des larves d’Aedes aegypti ont Ã©tÃ© Ã©chantillonnÃ©es en janvier 2018 dans des plantations immatures et matures dâ€™hÃ©vÃ©a, ainsi que dans les villages environnants aux plantations dâ€™hÃ©vÃ©a dans le dÃ©partement de Dabou. Des tests larvicides (Bacillus thuringiensis israelensis et tÃ©mÃ©phos) et adulticides (chlorpyriphos-mÃ©thyl 0.8%, malathion 0,1% et Fenitrithion 0,1%, permÃ©thrine 0,75%, deltamÃ©thrine 0,05%, lambdacyahalothrine 0,05%) en tube sur les gÃ©nÃ©rations F1 ont Ã©tÃ© rÃ©alisÃ©s conformÃ©ment aux directives de l’Organisation Mondiale de la SantÃ© (OMS). Les 3743 larves dâ€™Aedes aegypti testÃ©es ont Ã©tÃ© toutes sensibles aux deux larvicides avec des LC50 comprises entre 7.10-3 mg/L et 9.10-3 mg/L pour le Bacillus thuringiensis israelensis et entre 6,5.10-2 mg/L et 1,2.10-1 mg/L pour le tÃ©mÃ©phos. Les LC95 respectives Ã©taient comprises entre 2,1.10-2 mg/L et 2,4.10-2 mg/L et entre 6,5.10-2 mg/L et 1,2.10-1 mg/L. Aussi, 2400 Aedes aegypti adultes testÃ©s ont Ã©tÃ© tous sensibles aux organophosphorÃ©s (chlorpyriphos-mÃ©thyl 0.8%, malathion 0,1% et fenitrithion 0,1%) avec des mortalitÃ©s comprises entre 98% et 100% et aux pyrÃ©thrinoÃ¯des (permÃ©thrine 0,75%, deltamÃ©thrine 0,05%, lambdacyahalothrine 0,05%) avec des mortalitÃ©s de 100%. Lâ€™Ã©tude a montrÃ© que les populations immatures et adultes dâ€™Aedes aegypti des plantations dâ€™hÃ©vÃ©a et les villages environnants de la zone dâ€™Ã©tude Ã©taient sensibles au Bacillus thuringiensis israelensis, aux organophosphorÃ©s et aux pyrÃ©thrinoÃ¯des. The expansion of rubber cultivation is leading to a strong modification of the environment in CÃ´te d’Ivoire. As a result, several outbreaks of dengue and yellow fever caused by Aedes aegypti have recently been observed in CÃ´te d’Ivoire. The insecticide susceptibility profile of Aedes aegypti in these labourintensive mass farming areas is poorly known. This study established the susceptibility profile of Aedes aegypti in the rubber growing areas of Dabou in order to better plan control measures against the major arbovirus vector. Aedes aegypti larvae were sampled in January 2018 in immature and mature rubber plantations, as well as in the villages surrounding the rubber plantations in the Dabou department. Larvicidal (Bacillus thuringiensis israelensis and temephos) and adulticidal (chlorpyriphos-methyl 0.8%, malathion 0.1% and Fenitrithion 0.1%, permethrin 0.75%, deltamethrin 0.05%, lambdacyahalothrin 0.05%) tube tests on F1 generations were carried out in accordance with the World Health Organization (WHO) guidelines. All 3743 Aedes aegypti larvae tested were sensitive to both larvicides with LC50 ranging from 7.10-3 mg/L to 9.10-3 mg/L for Bacillus thuringiensis israelensis and from 6.5.10-2 mg/L to 1.2.10-1 mg/L for temephos. The respective LC95 were between 2.1.10-2 mg/L and 2.4.10-2 mg/L and between 6.5.10-2 mg/L and 1.2.10-1 mg/L. Also, 2400 adult Aedes aegypti tested were all sensitive to organophosphates (chlorpyrifos-methyl 0.8%, malathion 0.1% and fenitrithion 0.1%) with mortalities between 98% and 100% and to pyrethroids (permethrin 0.75%, deltamethrin 0.05%, lambdacyahalothrin 0.05%) with mortalities of 100%. The study showed that immature and adult populations of Aedes aegypti in rubber plantations and surrounding villages in the study area were susceptible to Bacillus thuringiensis israelensis, organophosphates and pyrethroids.