Insecticide resistance in the tiger mosquito, Aedes albopictus

Pyrethroids are the primary insecticides sprayed for mosquitoes in suburban North Carolina. These insecticides work by disrupting normal nerve cell function, causing a knockdown effect. Resistance to this effect is known as “knockdown resistance”, or kdr for short.

Researchers first genetically identified kdr mutations in Raleigh Ae. albopictus populations in 2020—only a dozen of 412 sampled mosquitoes possessed kdr mutations (Abernathy et al., 2022). Then, in 2023, I collected nearly 1,000 tiger mosquitoes from across Raleigh to assess the prevalence of kdr and examine the association between homeowners’ socioeconomic status and insecticide resistance in Ae. albopictus. We found that kdr frequency was significantly associated with higher property values and increased dramatically, rising explosively from 4.3% in the 2020 study to 52.1% in only three years.

These findings led to the publication of our results in Royal Society Open Science. We also published a companion paper in Parasites & Vectors that extended the mosquito sampling timeline to 2016-2024. You can find these papers here and here, respectively.