Insecticide resistance of Aedes albopictus in Nanchang,Jiangxi Province,2020 and 2023
Objective To investigate the current level and changing trend of resistance to commonly used insecticides in Aedes albopictus after emergency response to dengue fever outbreaks in Nanchang,Jiangxi Province,China,so as to provide a scientific basis for scientific insecticide use and dengue prevention and control.Methods Field Ae.albopictus larvae were collected from different habitats in 12 counties and districts of Nanchang in 2020 and 2023.They were mixed in equal quantities in each county or district and raised for 1-2 generations.The late third instars and early fourth instars and non-engorged female adults 3-5 days post eclosion were collected for insecticide resistance testing with the immersion test(for larvae)and the WHO tube test(for adults).Results The adult Ae.albopictus were sensitive to organophosphates(chlorpyrifos,fenitrothion,and malathion)and carbamates(propoxur and bendiocarb),with 24 h mortality rates of 98.67%-100%;likely resistant or resistant to pyrethroids deltamethrin and lambda-cyhalothrin,with 24 h mortality rates of 52.00%-84.00%;and resistant to permethrin and beta-cypermethrin,with 24 h mortality rates of 18.67%-70.67%.The larvae exhibited low to moderate resistance to propoxur(resistance ratio:7.30-12.70)and moderate to high resistance to temephos(resistance ratio:24.60-40.20).Conclusions The adult mosquitoes of Ae.albopictus in Nanchang have developed resistance to four pyrethroids insecticides including permethrin,and the larvae have developed moderate to high resistance to temephos.The resistance levels of Ae.albopictus to the same insecticides vary in different counties and districts.Therefore,insecticides should be used scientifically and reasonably based on the results of insecticide resistance surveillance to improve control effectiveness and delay resistance development.
万方数据
维普
