The L1014F Knockdown Resistance Mutation Is Not a Strong Correlate of Phenotypic Resistance to Pyrethroids in Florida Populations of <i>Culex quinquefasciatus</i>
Alden S. Estep,
Neil D. Sanscrainte,
Jason Stuck,
Isik Unlu,
Agne Prasauskas,
Stephanie J. Mundis,
Nicholas Cotter,
Ana L. Romero-Weaver,
Troy J. Fedirko,
Natalie L. Kendziorski,
Kyle J. Kosinski,
Daviela Ramirez,
Eva A. Buckner
Affiliations
Alden S. Estep
Mosquito & Fly Research Unit, Center for Medical, Agricultural and Veterinary Entomology, United States Department of Agriculture, 1700 SW 23rd Drive, Gainesville, FL 32608, USA
Neil D. Sanscrainte
Mosquito & Fly Research Unit, Center for Medical, Agricultural and Veterinary Entomology, United States Department of Agriculture, 1700 SW 23rd Drive, Gainesville, FL 32608, USA
Jason Stuck
Pinellas County Public Works—Environmental Management, 22211 U.S. Highway 19 North, Clearwater, FL 33765, USA
Isik Unlu
Miami-Dade County Mosquito Control Division, 8901 NW 58th Street, Miami, FL 33178, USA
Agne Prasauskas
Pasco County Mosquito Control District, 2308 Marathon Rd, Odessa, FL 33556, USA
Stephanie J. Mundis
Department of Geography, University of Florida, 330 Newell Dr, Gainesville, FL 32611, USA
Nicholas Cotter
Lee County Mosquito Control District, 15191 Homestead Road, Lehigh Acres, FL 33971, USA
Ana L. Romero-Weaver
Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, 200 9th St SE, Vero Beach, FL 32962, USA
Troy J. Fedirko
Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, 200 9th St SE, Vero Beach, FL 32962, USA
Natalie L. Kendziorski
Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, 200 9th St SE, Vero Beach, FL 32962, USA
Kyle J. Kosinski
Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, 200 9th St SE, Vero Beach, FL 32962, USA
Daviela Ramirez
Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, 200 9th St SE, Vero Beach, FL 32962, USA
Eva A. Buckner
Florida Medical Entomology Laboratory, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences, University of Florida, 200 9th St SE, Vero Beach, FL 32962, USA
Culex quinquefasciatus is an important target for vector control because of its ability to transmit pathogens that cause disease. Most populations are resistant to pyrethroids and often to organophosphates, the two most common classes of active ingredients used by public health agencies. A knockdown resistance (kdr) mutation, resulting in an amino acid change from a leucine to phenylalanine in the voltage gated sodium channel, is one mechanism contributing to the pyrethroid resistant phenotype. Enzymatic resistance has also been shown to play a very important role. Recent studies have shown strong resistance in populations even when kdr is relatively low, which indicates that factors other than kdr may be larger contributors to resistance. In this study, we examined, on a statewide scale (over 70 populations), the strength of the correlation between resistance in the CDC bottle bioassay and the kdr genotypes and allele frequencies. Spearman correlation analysis showed only moderate (−0.51) or weak (−0.29) correlation between the kdr genotype and permethrin or deltamethrin resistance, respectively. The frequency of the kdr allele was an even weaker correlate than genotype. These results indicate that assessing kdr in populations of Culex quinquefasciatus is not a good surrogate for phenotypic resistance testing.
