Malathion Insecticide Resistance Inaedes Aegypti: Laboratory Conditions Andin Situexperimental Approach Through Adult Entomological Surveillance

Objective In Brazil, the most common method of controlling outbreaks of arbovirus is by the use of chemical sprays, which kill the insect vector,Aedes aegypti. The main objective of this study was to evaluate the resistance ofAe. aegyptito the insecticide, malathion, in situ. The location of this study was the municipality of Foz do Iguacu, in the state of Parana, Brazil. Methods Ultra-low-volume (ULV) fogging equipment was used, by vehicle, to apply the insecticide in situ, and mosquito populations after treatment were compared with those of control areas. The resistance of strains collected from the municipality was compared to the Rockefeller strain under laboratory conditions. Results We found 220 adult female specimens and 7423 eggs ofAe. aegyptiin the areas subjected to UBV treatment, whereas 245 adult females and 10 557 eggs were found in the control areas. The UBV treatment area showed no significant difference compared to the control area, for all the indices. Mortality of the Rockefeller colony varied more quickly when there were slight variations in malathion concentration than the Foz do Iguacu population.