Analysis of the changes in insecticide resistance levels of Aedes albopictus in Hongkou District,Shanghai

XU Haodi; LIU Yuan; LIU Yao; LI Chunyan; LI Xin; ZHOU Yilun; WANG Bin; WANG Fei; LIU Hongxia

doi:10.19821/j.1671-2781.2025.06.004

Abstract：Objective To study the changes in the resistance levels of Aedes albopictus in Hongkou District,so as to provide a reference basis for mosquito control and the use of insecticides.Methods Mosquitoes were collected from one residential community and one park in each of the four directions(east,south,west,and north)of Hongkou District as fixed sampling sites.The larval dipping method recommended by WHO was used to determine the insecticide resistance of larvae Ae.albopictus.The contact tube method was used to determine the insecticide resistance of adult Ae.albopictus.Results The larvae Ae.albopictus showed low to moderate resistance to permethrin,with resistance ratios of 3.35 in 2015 and 14.74 in 2019,respectively.The larvae Ae.albopictus showed low to moderate resistance to fenthion,with resistance ratios of 17.05 in 2019,7.95 in 2021 and 13.99 in 2023,respectively.Except in 2015,the larvae Ae.albopictus showed low resistance to temephos,with resistance ratios of 0.30 in 2015,5.99 in 2019,5.93 in 2021 and 4.26 in 2023,respectively.The larvae Ae.albopictus had developed high resistance to deltamethrin,with resistance ratios of 43.50 in 2015 and 65.03 in 2021.There was no statistical difference in resistance among different insecticides(F=6.041,P=0.128).The adult Ae.albopictus developed resistance to permethrin,deltamethrin,beta-cypermethrin and lambda-cyhalothrin,possible resistance to propoxur,and sensitive to fenitrothion.Conclusion The adult and larvae Ae.albopictus in Hongkou District have developed different levels of resistance to different insecticides.It is recommended to reduce the use of fenthion and pyrethroid insecticides,use insecticides in rotation and alternation,and pay attention to the dosage.Meanwhile,health publicity and residents'awareness of mosquito prevention should be strengthen to achieve safe and sustainable mosquito control.