Impact of Aedes aegypti 1016I and 1534C knockdown resistance genotypes on operational interventions

Authors: Estep Iii, Alden; Sanscrainte, Neil; LAMBERG, FRIEDA - Florida Department Of Agriculture And Consumer Services; MCSTOOTS, DARREL - Osceola County Public Works Department; GOSSELIN, SUSAN - Osceola County Public Works Department

Submitted to: Insects
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/2/2024
Publication Date: 11/4/2024
Citation: Estep Iii, A.S., Sanscrainte, N.D., Lamberg, F., Mcstoots, D., Gosselin, S. 2024. Impact of Aedes aegypti 1016I and 1534C knockdown resistance genotypes on operational interventions. Insects. 15(11):863. https://doi.org/10.3390/insects15110863.
DOI: https://doi.org/10.3390/insects15110863

Interpretive Summary: In Aedes aegypti, resistance to pyrethroid insecticides is widespread and has been strongly linked to the presence of mutations in the voltage gated sodium channel. Distinct ensembles of these muta-tions are found in the Western Hemisphere and Indopacific with little known mixing. The Indo-pacific mutations have not previously been detected in the USA. We detected the presence of the V1016G and S989P mutations in three recent collections from Osceola County, Florida. These findings were confirmed using multiple methods and represent a significant expansion of the geographic range of these resistance factors. This requires modification of existing resistance screening protocols and further work to understand the operational implications for mosquito control.

Technical Abstract: Aedes aegypti is a major arboviral disease vector and is therefore a critical target for control by public health programs. Early eradication efforts have shown that Ae. aegypti can rapidly build insecticide resistance and now resistance to pyrethroids, the major class of adulticides used for operational control, is common in many populations. A major contributor to this resistance is a group of knockdown resistance (kdr) SNPs that normally exist in distinct ensembles in the Western Hemisphere and the Indopacific with little known mixing. In this study, we detected, and confirmed using multiple methods, the Indopacific kdr SNPs, both V1016G and S989P, in three recent collections from Osceola County, Florida. This represents a large expansion of the geographic range of the Indopacific kdr SNPs. We consider the implications of this finding on future insecticide resistance surveillance studies, including assessing the ability of our current screening tools to detect these SNPs. We find that the presence of the Indopacific SNPs requires modification of existing resistance screening protocols and requires further work to understand the operational implications for mosquito control.