Susceptibility of Culicidae Mosquitoes to Some Insecticides Recommended by WHO in a Malaria Endemic Area of Southeastern Iran

BACKGROUND: According to the national strategy plan on monitoring of insecticides resistance, this study was carried out to determine the base line susceptibility of the Culicidae mosquitoes to the WHO-recommended insecticides in an endemic focus of malaria in southeastern Iran. METHODS: Larval collection was carried out by dipping method and adult collection occurred by suction tube from January to December 2010. The susceptibility test was assessed to DDT 4 %, malathion 5 %, propoxur 0.1 %, deltamethrin 0.05 %, lambda-cyhalothrin 0.05 %, and cyfluthrin 0.15 % at different interval times (discriminative dose) followed by 24 h recovery period. The LT(50) and LT(90) values were calculated for plotting the regression line using Microsoft office Excel software ver. 2007. RESULTS: Anopheles stephensi was quite resistant to DDT and showed susceptible or tolerant to other insecticides. The LT(50) and LT(90) values to DDT in this species were 29.07, and 98.26 minutes, respectively. Anopheles culicifacies and Anopheles dthali were found susceptible or tolerant to insecticides. Culex pipiens was found resistance to DDT, propoxur, lambda-cyhalothrin and cyfluthrin whereas observed susceptible to malathion and tolerant to deltamethrin. Ochlerotatus caspius sl. was resistant to DDT, whereas found susceptible to other insecticides. Culisita longiareolata was susceptible to deltamethrin, whereas tolerant to other insecticides. The LT(50) and LT(90) values of Cs. longiareolata to DDT were 17.82, and 51.26 minutes. CONCLUSION: We suggested the same study in different parts of the country for monitoring and evaluation of control measures.