Insecticide susceptibility monitoring
The susceptibility of the vector population in the study area to relevant insecticides was assessed at baseline and at 3- and 10-months post IRS intervention. Mosquitoes for susceptibility bioassays were sampled as larvae from breeding sites in selected clusters within the study area and raised to F1 in the insectary before testing. Villages/clusters were selected based on their accessibility and on availability of mosquito larval breeding sites. Bottle bioassays were used to assess the susceptibility of mosquitoes from each village to clothianidin and broflanilide. Clothianidin was tested at a discriminating dose of 90 µg/bottle as specified by the manufacturer while broflanilide was tested at 6 µg/bottle as determined in preliminary dose–response bioassays