Resistance levels of nine mosquito species to 4% DDT in Phnom Penh, Kampuchea.

According to the standard WHO method criteria, the mosquitoes Anopheles campestris and Culex vishnui were found to be susceptible to DDT in the territory of Phnom Penh. An. vagus and An. sinensis were approximately at the limit of susceptibility and the remaining five species (Aedes vexans, Cx. tritaeniorhynchus, Cx. fuscocephala, Cx. gelidus, Cx. bitaeniorhynchus) were found to be more or less resistant. Except for An. vagus, the males of all species were more susceptible than the females.