Kristina Lopez, a PhD student in Entomology advised by Dr. Susan Paskewitz, was awarded the 2022 Dan Strickman Memorial Award for Best Student Presentation at the 2022 Society of Vector Ecology International Congress. Read below for more information about her presentation. Congratulations Kristina!
Title: Insecticide resistance status of West Nile Virus vectors in the Chicago suburbs
Authors: Kristina Lopez1, Patrick Irwin1,2, Edwin Burgess IV3, Alden Estep4, Colin P Jaeger5, Susan Paskewitz1, Lyric Bartholomay1
1 University of Wisconsin – Madison
2 Northwest Mosquito Abatement District
3 University of Florida
4 USDA-ARS Center for Medical, Agricultural, and Veterinary Entomology
5 McHenry County College
Abstract: Minimal reduction in mosquito abundance post adulticide application, and mounting evidence of adulticide product failure prompted evaluation of insecticide resistance for West Nile virus vectors in the greater Chicago area, Illinois, USA. We conducted CDC bottle bioassays, topical applications, and caged field trials on susceptible Culex pipiens, field collected Cx. pipiens, and field collected Cx. restuans. Field- collected mosquitoes were acquired from six study sites that were previously used in adulticide efficacy experiments. These mosquitoes were subjected to: 1) bottle bioassays with exposure to etofenprox, d-phenothrin, and synergized d-phenothrin; 2) caged field trials with synergized d-phenothrin (Anvil 10+10); and 3) topical applications with synergized and unsynergized etofenprox, d-phenothrin, and deltamethrin. Etofenprox and synergized d-phenothrin have both previously been used in adulticide applications with varying frequencies in this area. Results from the three evaluations showed field collected Cx. pipiens were resistant to all active ingredients tested, and field collected Cx. restuans were susceptible. The intensity of insecticide resistance was not consistent across sites, despite all being within 10 km from one another. Investigations are ongoing to determine the cause of these observations, including frequency of past adulticide applications, genotyping, and enzymatic activities of each population. Enzymatic activity analyses are ongoing, and significant differences have been detected across sites. Field-collected Cx. pipiens from all six sites were positive for at least one copy of the 1014F allele, commonly associated with knock-down resistance in mosquitoes.
Earlier this year, Kristina was also awarded the Hollandsworth Prize for the 2022 AMCA Student Competition for her presentation on this research at the American Mosquito Control Association Annual Meeting.
This article was posted in Awards, News and tagged Kristina Lopez, Susan Paskewitz.