Target Site Insensitivity Detection in Deltamethrin Resistant Culex pipiens Complex in Iran

Background: some mosquito species which belong to the culex. pipiens complex are primary vectors for west nile virus, sindbis, dirofilaria immitis, and many arboviruses. knockdown resistance (kdr) mutations in the voltage-gated sodium channel (vgsc) gene of cx. pipiens that is inherited, is one of the important threats for the efficacy of pyrethroids insecticides. knockdown resistance (kdr) mutation, l1014f, is a well-defined mechanism of resistance to pyrethroids and ddt in many insect species. the aim of study was to determine the mechanisms of insecticide resistance in this species. methods: specimens of cx. pipiens, the major vector of west nile virus, were obtained in tehran, iran by col-lecting larvae from polluted wastewater in qarchak of tehran. in 2016 insecticide susceptibility tests were performed according to who methods with deltamethrin 0.05%. we focused on determination of this point mutation in the vgsc gene of cx. pipiens by real-time pcr. results: our results revealed high levels of resistance to deltamethrin 0.05%. the lethal times i.e. lt50 and lt90 for deltamethrin were 2.1530 and 8.5117 h respectively. the result of real-time pcr confirmed the presence of resistant genotype in all the members of tested population. this study is the first report on kdr geno-typing of cx. pipiens from tehran and our results on the vgsc gene in position l1014f confirmed the tta to ttt nucleotide change. conclusion: this finding will provide a clue for management of insecticide resistance in mosquito which are vectors of arboviruses and decision for replacement of novel approach for vector control.