Continued susceptibility of the wMEL wolbachia infection in Aedes aegypti to heat stress following field deployment and selection

Abstract

Aedes aegypti mosquitoes infected with the wMel strain of Wolbachia are being deployed to control the spread of arboviruses around the world through blockage of viral transmission. Blockage by Wolbachia in some scenarios may be affected by the susceptibility of wMel to cyclical heat stress during mosquito larval development. We therefore evaluated the potential to generate a heat-resistant strain of wMel in Ae. aegypti through artificial laboratory selection and through exposure to field temperatures across multiple generations. To generate an artificially selected strain, wMel-infected females reared under cyclical heat stress were crossed to wMel-infected males reared at 26◦C. The low prop..