Residual efficacy of the neonicotinoid insecticide clothianidin against pyrethroid‐resistant Aedes aegypti

BACKGROUND Here we report the residual efficacy of the neonicotinoid insecticide clothianidin against pyrethroid‐resistant Aedes aegypti. We first conducted a range‐finding evaluation of clothianidin on three different substrates (wall, wood, cloth) using three doses (100, 300 and 600 mg a.i. m−2) and conducting World Health Organization (WHO) cone bioassays to assess acute (24 h) and delayed (up to 7 days) mortality. In experimental houses located in Merida (Mexico) and using free‐flying pyrethroid‐resistant Ae. aegypti females, we quantified the acute and delayed mortality after a 24‐h exposure to the targeted indoor residual spraying (TIRS) of two clothianidin doses (100 and 300 mg a.i. m−2). RESULTS Range‐finding studies with WHO cones showed low (