ABSTRACT
Stegomyia aegypti (Linnaeus, 1762) vectors arboviruses of public health concern in urban areas of tropical countries, so it is necessary to reduce its population. Among the control methods used, chemically synthesized molecules have been widely employed, nonetheless, the over usage of the same mechanism of action can result in the resistance selection. Considering the influence of insect resistance with the success of chemical control of vectors, this study aims to assess the susceptibility to organophosphorus of a population of S. aegypti from Paranaguá (Paraná, Brazil), after intense use of malathion during a dengue outbreak. World Health Organization susceptibility tests and expression of Acetylcholinesterase ace-1, cytochrome P450 monooxygenase CYP6N12, and α-esterases CCEae3A genes were evaluated. The mortality rate of wild females (66.5%) indicated their resistance status, furthermore, a new discriminant concentration was detected in this population (3.41%). Exclusively CYP6N12 gene was overexpressed in malathion-resistant females indicating its possible contribution to the transformation of this insecticide. Constant monitoring of insecticide resistance of current and past molecules, mainly in port areas where there is a large flow of species, is crucial for effective use of insecticide in vector control programs.
KEY WORDS:
Acetylcholinesterase; Aedes; cytochrome P450 monooxygenase; discriminant concentration; malathion; α-esterase
Thumbnail
Thumbnail
Thumbnail
