Co-occurrence of kdr mutations V1016I and F1534C in pyrethroid-resistant Aedes aegypti (Diptera: Culicidae) populations from Costa Rica

Abstract

Aedes aegypti (Linnaeus, 1762) is considered the most important mosquito vector species for several arboviruses (e.g., dengue, chikungunya, Zika) in Costa Rica. The main strategy for the control and prevention of Aedes-borne diseases relies on insecticide-based vector control. However, the emergence of insecticide resistance in the mosquito populations present a big threat for the prevention actions. The characterization of the mechanisms driving the insecticide resistance in Ae. aegypti are vital for decision making in vector control programs. Therefore, we analyzed the voltage-gated sodium channel gene for the presence of the V1016I and F1534C kdr mutations in pyrethroid-resistant Ae. aegypti populations from Puntarenas and Limon provinces, Costa Rica. The CDC bottle bioassays showed that both Costa Rican Ae. aegypti populations were resistant to permethrin and deltamethrin. In the case of kdr genotyping, results revealed the co-occurrence of V1016I and F1534C mutations in permethrin and deltamethrin-resistant populations, as well as the fixation of the 1534C allele. Therefore, our findings make an urgent call to expand the knowledge about the insecticide resistance status and mechanisms in the Costa Rican populations of Ae. aegypti which must be a priority to develop an effective resistance management plan.