Fast emerging insecticide resistance in < i > Aedes albopictus < /i > in Guangzhou, China: Alarm to the dengue epidemic

In this study,Ae.albopictus were collected from four districts with varied dengue virus transmission intensity in Guangzhou from 2015 to 2017. AdultAe.albopictus insecticide susceptibility to deltamethrin (0.03%), permethrin(0.25%), DDT(4%), malathion (0.8%) and bendiocarb (0.1%) was determined by the standard WHO tube test, and larval resistance bioassays were conducted using temephos,Bacillus thuringiensis israelensis (Bti), pyriproxyfen (PPF) and hexaflumuron. Mutations at the voltage-gated sodium channel (VGSC) gene and acetylcholinesterase (AChE) gene were analyzed. The effect of cytochrome P450s on the resistance ofAe.albopictus to deltamethrin was tested using the synergistic agent piperonyl butoxide (PBO). The results showed thatAe.albopictus populations have rapidly developed very high resistances to multiple commonly used insecticides at all study areas except malathion,Bti and hexaflumuron. We found 1534 codon mutations in the VGSC gene that were significantly correlated with the resistance to pyrethroids and DDT, and 11 synonymous mutations were also found in the gene. The resistance to deltamethrin can be significantly reduced by PBO but may generated cross-resistance to PPF. Fast emerging resistance inAe.albopictus may affect mosquito management and threaten the prevention and control of dengue, similar to the resistance inAnopheles mosquitoes has prevented the elimination of malaria and call for timely and guided insecticide management.
Source: PLoS Neglected Tropical Diseases - Category: Tropical Medicine Authors: Source Type: research