Prevalence of Knock-Down Resistance F1534S Mutations in Aedes albopictus (Skuse) (Diptera: Culicidae) in North Carolina

Abstract

Knock-down resistance (kdr) mutations in the voltage-gated sodium channel gene of Aedes species mosquitoes are biomarkers for resistance to pyrethroid insecticides. In the United States, few studies have reported kdr mutations among Aedes albopictus (Skuse) (Diptera: Culicidae) populations. In this study, we sought to compare the presence of kdr alleles among Ae. albopictus mosquitoes collected from Fort Bragg and Wake County, North Carolina. We collected 538 Ae. albopictus mosquitoes, including 156 from 4 sites at Fort Bragg, North Carolina and 382 from 15 sites in Wake County, North Carolina to compare the prevalence of kdr mutations. Of those successfully sequenced, we identified 12 (3.0%) mosquitoes with kdr mutations, all of which were attributed to variants at position 1534 within domain 3. All mutations were found in mosquitoes collected at Wake County sites; no mutations were identified in collections from Fort Bragg. There was a focus of mutations observed at the Wake County sites with approximately 92% (11 of 12) of the mosquitoes with the mutation coming from one site, where kdr mutations represented 24.4% (11 of 45) of all mosquitoes collected. We observed highly focal resistance in a suburban area of Raleigh, which may be attributable to peri-domestic mosquito control activities that involve area dispersal of pyrethroid insecticides. More robust surveillance is needed to monitor the emergence and spread of resistance.

Molecular analysis of knockdown resistance (kdr) mutations in the voltage-gated sodium channel gene of Aedes aegypti populations from Saudi Arabia

“…F1534S has been reported as a kdr mutation in Ae. albopictus collected from the United States and China [ 64 , 65 ] and its resistance status in Ae. aegypti should be tested.…”

Critical Review of Insecticide Resistance in Us Aedes Albopictus: Resistance Status, Underlying Mechanisms, and Directions for Future Research

“…Both 1534L and 1534S were identified in a 2016 study with 1534S detected in a Florida population (Xu et al 2016). Twenty-five percent of tested North Carolina populations contained some organisms with 1534L (Abernathy et al 2022). Findings of few kdr mutations in US populations could be simply due to a lack of widespread assessment but may also be explained by the phenotypic resistance data.…”

Persistent variation in insecticide resistance intensity in container breeding Aedes (Diptera: Culicidae) co-collected in Houston, TX

“…There does appear to be increasing levels of kdr like SNPs and resistance in China, but these SNPs have not yet been determined to be present in the United States (Auteri et al 2018). A recent study from North Carolina did identify 1 strain (of 9 tested) with the presence of a kdr -like F1534S SNP, however, no bioassay was conducted to show if this population was more resistant than those without the SNP (Abernathy et al 2022). Two studies from Florida that quantified the level of permethrin resistance found that resistance ratios (RRs) were very low (less than 2.5-fold compared to the control), but they did not examine the NaV for the presence of SNPs (Waits et al 2017, Estep et al 2018).…”