Oxidase-based DDT-pyrethroid cross-resistance in guatemalan Anopheles albimanus

An oxidase resistance mechanism producing DDT-pyrethroid cross-resistance h as been identified in an isofemale line of Guatemalan Anopheles albimanus W iedemann through application of bottle bioassays and biochemical analysis. The resistance is fully synergized by piperonyl butoxide. Oxidase resistanc e in individuals may be detected and levels measured using a microplate ass ay. Only adult female mosquitoes express the oxidase mechanism. In the pare nt strain, an additional pyrethroid resistance mechanism, an elevated ester ase, coexists with the oxidase. Mosquitoes with the oxidase resistance show induction by phenobarbital and sublethal pyrethroid exposure. (C)1999 Acad emic Press.