The detection and significance of emerging insecticide resistance in mosquitoes

Abstract

Mosquito-borne arboviruses are increasing in incidence around the world. Australia enjoys some protection from pests and diseases afforded by its geographic isolation coupled with strict biosecurity control at its borders. However, as the volume of global trade, travel and transport expands, risk of exotic incursions to Australia is increasing. Detection of foreign mosquitoes at airports and seaports around Australia is becoming commonplace. The Asian tiger mosquito, Aedes albopictus, which has expanded its range throughout Europe and the Americas1, has not become established in mainland Australia, but is encountered as an exotic incursion2. The yellow fever mosquito and dengue vector, Aedes. aegypti, occurs naturally in northern Queensland, but is also captured at Australia's ports on a recurrent basis as an incursion from overseas3. Although Ae. aegypti is established in Australia, its detection as an incursion is still cause for concern. Apart from the possibility that invasive mosquitoes will carry exotic arboviruses, genetic characteristics of a foreign insect population can be very different from those observed in local mosquitoes, particularly in terms of insecticide resistance. Our recent researchhasshownthat invadingmosquitoesfromoverseas carry insecticide resistance alleles not found in Australia4 and our development of a global genomic database is helping us to pinpoint their source.