Heme peroxidase activity measured in single mosquitoes identifies individuals expressing an elevated oxidase for insecticide resistance.

Optimum conditions are described for a simple, rapid, microplate-based assay that indirectly measures the differences in oxidase levels between individual susceptible, resistant, or induced mosquitoes. A small proportion (0.01-0.1) of a single mosquito is used, allowing multiple replicates of the oxidase assay. Cytochrome C is used as a positive control. The levels of oxidase found in sample populations of pyrethroid-susceptible, pyrethroid-resistant, and phenobarbital-induced Anopheles albimanus mosquitoes are characterized with the assay.