Insecticide resistance alleles in wetland and residential populations of the West Nile virus vector Culex pipiens in New Jersey.
BACKGROUND
In spite of the extensive use of insecticides to control Culex pipiens in the aftermath of West Nile virus, knowledge of the spatial distribution and frequency of insecticide resistance in this species is poorly understood in the United States. This paper reports on the occurrence of upregulated esterases that detoxify organophosphates (OPs) and mutations conferring resistance to pyrethroid insecticides in natural and developed areas of New Jersey.


RESULTS
We report the first observations of the OP resistance alleles Ester(B1) and Ester(2) and the classical knockdown resistance (kdr) mutation L1014F in New Jersey Cx. pipiens. Upregulated Ester(B1) peaked at 23% (mean ± SE = 12 ± 2.3%) and Ester(2) at 14% (8 ± 1.8%), and both were widely distributed. L1014F, which confers strong resistance to pyrethroids when homozygous, was also widely distributed and ranged in frequency from 2 to 19% (5.1% heterozygous individuals and 1.4% homozygous).


CONCLUSION
We have demonstrated that OP resistance is common and broadly distributed in New Jersey Cx. pipiens, and that homozygous individuals resistant to pyrethroids are present. Further, we have detected double mutants at Ester and kdr, a condition that may annul the purging effects of insecticide rotations. Our results therefore indicate the need for continued monitoring of insecticide resistance in order to achieve effective mosquito control.
['Johnson|Brian J|BJ|', 'Fonseca|Dina M|DM|']
D000483:Alleles D000818:Animals D002947:Cities D003465:Culex D019476:Insect Proteins D007305:Insecticide Resistance D007306:Insecticides D009032:Mosquito Control D009515:New Jersey D010755:Organophosphates D011722:Pyrethrins D015854:Up-Regulation D053833:Wetlands
esterase organophosphates pyrethroids kdr integrated pest management vector-borne disease