Abstract
Agrochemicals have been successfully repurposed to control mosquitoes worldwide, but pesticides used in agriculture challenge their effectiveness by contaminating surface waters and driving insecticide resistance in larval populations. Here we implemented a new experimental approach to predict the efficacy of agricultural pesticides newly repurposed for malaria vector control. We mimicked insecticide resistance selection as it occurs in contaminated aquatic habitats by rearing field-collected mosquito larvae in water containing a dose of insecticide at which 100% of individuals from a susceptible strain died within 24 h. We then simultaneously monitored short-term lethal toxicity within 24 h and sublethal effects for 7 days. We found that due to chronic exposure to agricultural pesticides some mosquito populations are currently predisposed to rapidly adapt to neonicotinoids if they were used in vector control. Larvae collected from rural and agricultural areas where neonicotinoid formulations are intensively used for insect pest management were able to survive, grow, pupate and emerge in lethal doses of acetamiprid, imidacloprid and clothianidin. These results emphasize the importance of addressing prior exposure of larvae to formulations used in agriculture before applying agrochemicals against malaria vectors.
Competing Interest Statement
The authors have declared no competing interest.
