Determining the status of susceptibility to organophosphate, carbamate and pyrethroids insectioides in populations of Aedes aegypti Linneaus, 1762 (Diptera: Culicidae) in Panama

Introduction: We studied the susceptibility to organophosphate, carbamate and pyrethroid insecticides of Aedes aegypti from different regions of high transmission risk for dengue in Panama. Objective: To evaluate the susceptibility to organophosphate, carbamate and pyrethroid insecticides in Ae. aegypti from eight sites belonging to seven municipalities in Panama. Materials and methods: We collected Ae. aegypti larval populations in different types of breeding sites located in urban areas. Insects were reared in laboratory control conditions. With the F-1 generation of each strain we performed susceptibility bioassays using WHO standardized methodology for larvae and adults. Results: The eight Ae. Aegypti strains were susceptible to the pyrethroid insecticides: deltamethrin, lambdacyhalothrin and cifluthrin, to the organophosphate fenitrothrion, and to the carbamates propoxur and bendiocarb. Only the CHITRE strain exhibited a moderate resistance to the insecticide deltamethrin in larvae (FR50=5x). However, adults were susceptible. Conclusions: It is necessary to perform periodic surveillance to evaluate the susceptibility of Ae. aegypti populations in the studied municipalities with the purpose of preserving their susceptible. The insecticides applied for Ae. aegypti control can still be used in the evaluated municipalities; however it will depend on the susceptibility of the mosquitoes in the specific area.