Detection of Permethrin Resistance and Associated Mutations in Aedes aegypti mosquitoes within Pune Municipal Corporation, Maharashtra

Aedes aegypti is the primary vector for arboviral diseases, like dengue, chikungunya, and Zika viral infection. Vector control based on insecticide remains a primary strategy due to the lack of effective vaccines, particularly in outbreak situations. However, widespread pyrethroid use has led to the emergence of insecticide resistance in Aedes populations. Here, we investigated the susceptibility of Ae. aegypti from nine areas within the Pune Municipal Corporation area of Maharashtra, to 0.75% permethrin using WHO susceptibility tests. We observed varying patterns of insecticide susceptibility within the wards of Pune Municipal Corporation area. Resistance was observed in Aedes mosquitoes from six localities whereas three wards remained susceptible. PCR amplification followed by Sanger sequencing revealed point mutations linked to resistance against pyrethroids. In domain II (S6), mutations S989P and V1016G were detected in mosquitoes from 2 localities Pashan and Kondhwa. The F1534C mutation was found in populations from Khadki, Susgaon, Warje, Yerwada, and Hadapsar, as shown by Domain III S6 analysis. Additionally, the T1520I mutation was detected exclusively in mosquitoes from the Hadapsar locality. No D1763Y mutation was found in domain IV S5-6. Different levels of susceptibility and varied mutations were found among the wards of PMC. The findings underscore the need for continued resistance monitoring and developing appropriate integrated vector management strategies at the local level.