Insecticide resistance, sensitivity to N,N-diethylmethylbenzamide (DEET) and locomotor activity of Aedes aegypti and Aedes albopictus (Diptera: Culicidae)

Abstract

Dengue, Zika and chikungunya are arboviruses of great importance for Public Health, being transmitted mainly by the Aedes aegypti mosquito. In Brazil, Aedes albopictus is considered a potential vector of these arboviruses, which makes better knowledge about the behavior of this species essential. For the control of Ae. aegypti, the methods mainly used are mechanical and chemical, which is carried out through the use of insecticides. However, high exposure to insecticides can result in the selection of populations of resistant mosquito vectors, making their control difficult. Another method to avoid contact with Ae. aegypti is through the use of repellents, the most used being those based on DEET. Pioneering experiments carried out with Ae. aegypti showed that exposure to DEET can lead to a decrease in the repellency effect, not preventing the blood meal. The association between insecticide resistance and repellent insensitivity is unclear and sometimes contradictory. Both Ae. aegypti and Ae. albopictus have diurnal/twilight activity. It has already been shown that dengue and Zika virus infection affects the locomotor activity of Ae. aegypti, but nothing is known for Ae. albopictus. Thus, the objective of this project is to evaluate aspects related to insecticide resistance, DEET sensitivity and locomotor activity of Ae. aegypti and Ae. albopictus. In the first part, eggs of Ae. aegypti will be collected in 5 Brazilian cities, one in each region of the country. Tests for insecticide resistance and DEET repellency tests will be carried out. The locomotor activity of populations with different levels of resistance will also be evaluated. For the locomotor activity of females of Ae. aegypti and Ae.albopictus infected with Zika virus, infection will occur through intrathoracic injection and oral feeding. Thus, in this project, we intend to describe the relationship between DEET sensitivity and resistance to different classes of insecticides in Ae. aegypti, as well to better understand the interaction between pathogen (ZIKV) and vector (Ae. aegypti and Ae. albopictus) under laboratory conditions. (AU)