Background: In Panama, arboviroses such as dengue fever, and more recently chikungunya fever and Zika disease, are transmitted by Aedes aegypti and Aedes albopictus. Their control is based on the elimination of breeding sites and fogging with pyrethroid insecticides. However, one of the significant issues derived from the prolonged use of pyrethroid insecticide is the development of resistance mechanisms, such as knockdown resistance or kdr. The objective of this study was to evaluate the presence of kdr mutations in a partial region of the VGSC gene in samples of wild-caught Aedes mosquitoes from different locations of the Metropolitan Region of Panama.
Results: Based on the analysis of 194 sequences of the VGSC gene, two kdr mutations (Ile1011Met and Val1016Gly) were detected in a specimen of Ae. aegypti. The frequency of kdr mutations in the evaluated samples of Ae. aegypti was 0.01.
Conclusions: This study provides evidence for a low frequency of kdr mutations in Ae. aegypti populations in Panama. It is possible that these changes have no impact on vector control interventions. To our knowledge, we report, for the first time in America the Val1016Gly mutation documented in Asia. In general terms, this result is highly relevant to the Aedes Control Programme in Panama since it constitutes a feasible approach for the timely detection of resistance as well as for the development of strategies.
Keywords: Aedes aegypti; Aedes albopictus; Panama; Pyrethroid resistance; Voltage-gated sodium channel; kdr mutations.