Aedes aegypti (L.) (Diptera: Culicidae) control programmes in Cuba rely on the application of the
organophosphate temephos for larval control. Hence, the monitoring of resistance to this
insecticide is an essential component of such programmes. Here, 15 field populations from different municipalities of Havana City were assayed for resistance to
temephos. High levels of resistance were detected in all strains and resistance ratios were highly correlated with
esterase activity (P = 0.00001). Populations from three municipalities were tested in both 2006 and 2008; resistance and
esterase activities both significantly increased during this 2-year period. Synergist studies demonstrated that neither
glutathione transferases nor
monooxygenases were associated with the increase in resistance to
temephos in this period. The duration of the efficacy of commercial formulations of
temephos in controlling Ae. aegypti populations in Havana City was reduced by the high level of
temephos resistance observed; hence these data are of clear operational significance for the
dengue control programme in Cuba. New integrated strategies to avoid further increases in
temephos resistance in Cuba are necessary.