Detection of Insecticide Susceptibility Status and KDR Mutation in Field-Collected Aedes Aegypti from Different Districts of Punjab, India

Abstract

Background: As the state of Punjab has become endemic for dengue, this study was planned to determine the susceptibility status for two different classes of adulticides and the VGSC gene polymorphism in domain II of Aedes aegypti. Methodology: Adult bioassays were performed with pyrethrum, deltamethrin and malathion as per the WHO protocol. AS-PCR and sequencing of VGSC gene were carried out to detect V1016G and Kdr (Knockdown resistance) mutations. Results: Ae. aegypti from the districts of Ludhiana and Patiala were found to be resistant to pyrethrum. The V/V genotype frequency was found to be higher in all districts. Three known polymorphisms in VGSC gene were not recorded but one synonymous and non-synonymous mutation was found. Group B intron was found in domain II of the VGSC gene. For deltamethrin and malathion, 100% susceptibility was recorded for all four districts. Conclusion: Thus, the present findings indicate 100% susceptibility towards deltamethrin and malathion whereas, moderate resistance towards pyrethrum was recorded. Therefore, more studies should be planned to study polymorphisms in the various domains of the VGSC gene.