Ecological surveillance of mosquitoes and their virus infection in Xiamen from 2016 to 2023

WU Sihan; KE Xuemei; GUO Zhinan; MA Shanshan; CAI Chunxiang; XU Xuerong; WANG Xiaoyan

doi:10.19821/j.1671-2781.2025.04.011

Abstract：Objective To understand the mosquito species composition,population density,seasonal fluctuation and virus carriying status in Xiamen,Fujian Province,and to provide a basis for the prevention and control of mosquitoes and mosquito-borne diseases.Methods Monitoring sites were set up in two districts of Xiamen,Huli and Jimei,and adult mosquito density monitoring was carried out from 2016 to 2023 by using the mosquito trapping lamp method,and adult mosquitoes were collected in all districts of the city in May-July from 2021 to 2023 and fluorescence quantitative PCR was applied to detect the dengue virus,yellow fever virus,Sindbisvirus,chikungunya virus,Japanese encephalitis virus,and West Nile virus.Chi-square test was used to compare the difference of species composition in different years and different habitats.Kruskal-Wallis non-parametric test was used to compare the difference of density in different years and different months.Results From 2016 to 2023,a total of 3 262 mosquito trapping lamps were deployed and 3 869 female mosquitoes were captured,with an average mosquito density of 1.2 mosquitoes/(lamp·night),and the dominant mosquito species was Cx.pipiens quinquefasciatus.The general inter-annual fluctuation of mosquito density during the 8-year period showed a smooth trend.There were statistical differences in the species composition between different habitats(χ2=39.972,P＜0.001),with the highest density of mosquitoes in livestock sheds.Mosquito densities in different habitats showed a bimodal curve,with a rapid increase starting in March,peaking in May,a continuous decline from June to August,a small peak in October followed by a rapid decline in mosquito densities,and February being the lowest point of the year.The results of the pathogenetic tests showed a positive rate of 0.6%for the Japanese encephalitis virus of Cx.pipiens quinquefasciatus,while the rest of the samples were negative.Conclusion The dominant mosquito species in Xiamen is Cx.pipiens quinquefasciatus,and mosquito density in livestock sheds is higher.April to October is the peak period for mosquito activity,and Japanese encephalitis virus has been detected in the mosquitoes.Comprehensive control measures focusing on environmental management and supplemented by insecticide application are needed to prevent the occurrence and prevalence of mosquito-borne diseases.