Poster Display
Medical, Urban, and Veterinary Entomology
Jennifer F. Baltzegar
Assistant Professor
Augusta University
Clarks Hill, South Carolina
Amy Morrison
University of California
Iquitos, Loreto, Peru
Fred L. Gould
North Carolina State University
Raleigh, North Carolina
The mosquito, Aedes aegypti, is the primary vector of dengue, chikungunya, zika, and yellow fever viruses. Dengue currently infects ~400 million people annually, but it is expected to threaten 60% of the world’s population by the year 2080 due to an expanding distribution of mosquito populations caused by climate change. Chemical insecticides remain the primary method of reducing mosquito populations, but resistance inhibits their efficacy. We aim to better understand resistance evolution to maintain mosquito control programs. We previously found that two functional SNPs associated with pyrethroid resistance, F1534C and V1016I, rose to high frequencies at separate times within the Ae. aegypti population in Iquitos, Peru during a 12-year period of selection. Here, we further investigate the diplotypes that contain the resistance loci and aim to elucidate the genetic dynamics that led to the rapid evolution of insecticide resistance in this population. We examine diplotypes containing the functional SNPs at three different timepoints during pyrethroid selection: before pyrethroids, during the rise of F1534C, and during the rise of V1016I. As expected, we find a decrease in the number of diplotypes immediately following the initial application of pyrethroids within the city. We also observe that different resistance diplotypes dominate the population during the independent selection of the functional SNPs. Interestingly, the resistance diplotype that is most dominant at the final time point (selection of V1016I) was not the primary diplotype present during the selection of F1534C, but was present in the population prior to pyrethroid spray in its susceptible form.