2022年四川省传疟媒介监测结果分析

Analysis of the surveillance results of malaria vectors in Sichuan Province in 2022

目的分析四川省监测县传疟媒介种群分布、密度及季节消长情况,为消除疟疾后疫点处置提供参考。方法2022年5至9月随机选取了73个传疟媒介种群调查监测县和23个种群和密度调查监测县分别通过灯诱法和人帐诱法开展种群和密度监测,对捕获到的蚊虫进行形态学鉴定,对捕获蚊虫、按蚊数量、密度利用WPS Office软件建立数据库,用SPSS26.0软件进行方差分析和卡方检验等描述性统计分析,检验水准为α=0.05。结果2022年在5至9月期间有165个点开展种群监测,23个点开展了密度监测。共捕获180402只蚊虫,其中按蚊有26521只(14.70%)。中华按蚊26274只(99.07%),嗜人按蚊19只(0.07%),未鉴定按蚊种70只(0.26%),未捕获到微小按蚊和大劣按蚊。通过灯诱法捕获到民房外3712只中华按蚊(15.45%),牲畜房14390只(59.88%),可孳生地5927只(24.67%);仅青神县和洪雅县捕获到18只嗜人按蚊;未鉴定的按蚊位于资中县;不同场所中华按蚊和嗜人按蚊构成差异有统计学意义(χ^(2)=29.33,P<0.001)。有16个区县未监测到按蚊,武胜县捕获的中华按蚊最多,不同场所监测到中华按蚊密度差异无统计学意义(χ^(2)=15.66,P=0.11)。通过人帐诱法除安岳县外其他22个县均捕获到中华按蚊(2403只),仅青神县捕获到1只嗜人按蚊,中华按蚊平均密度为2.09只/(人·时)。晚上8时~9时捕获到中华按蚊最高(436只),密度为3.79只/(人·时),不同时间段捕获中华按蚊数量上差异有统计学意义(F=1751.96,P<0.001)。6月下旬捕获到中华按蚊最多(720只),密度为3.13只/(人·时),不同月份捕获中华按蚊数量上差异也有统计学意义(F=2176.56,P<0.001);达川区、洪雅县2个地区每月每个时间段都捕获有中华按蚊。结论四川省传疟媒介持续存在,输入性疟疾病例时有发生,应继续加强传疟媒介监测工作,采用合适的方法,综合评估疫点情况,及时采取有效媒介控制措施,合理、科学地处置疫点工作,守好消除疟疾成果,防止出现输入性继发二代病例。

Objective To analyze the distribution,density and seasonal fluctuation of malaria vector populations in monitoring counties in Sichuan Province,and to provide reference for the disposal of epidemic sites after malaria elimination.Methods From May to September 2022,73 malaria vector population survey monitoring counties and 23 population and density survey monitoring counties were randomly selected to carry out population and density monitoring by light trap method and human tent trap method,respectively.Morphological identification was carried out on the captured mosquitoes.A database of the number and density of captured mosquitoes and Anopheles mosquitoes was established by WPS Office software.SPSS 26.0 was used for descriptive statistical analysis such as variance analysis and Chi-square test,and the test level wasα=0.05.Results In 2022,population monitoring was carried out at 165 sites and density monitoring at 23 sites from May to September.A total of 180402 mosquitoes were captured,of which 26521(14.70%)were Anopheles mosquitoes.There were 26274 Anopheles sinensis mosquitoes(99.07%),19(0.07%)Anopheles anthropophilia and 70(0.26%)Anopheles species not identified,and no Anopheles minorum and Anopheles macrophyllum were captured.A total of 3712 Anopheles sinensis(15.45%)were captured outside houses,14390(59.88%)in livestock houses,and 5927(24.67%)in breeding areas by light trapping.Only 18 Anopheles anthropophilia were captured in Qingshen County and Hongya County.The unidentified Anopheles mosquitoes were captured in Zizhong County.There were statistically significant differences in the composition of Anopheles sinensis mosquitoes and Anopheles anthropophilia in different places(χ^(2)=29.33,P<0.001).There were 16districts and counties that did not capture Anopheles mosquitoes,and Wusheng County caught the most Anopheles sinensis.There was no significant difference in the density of Anopheles sinensis mosquitoes detected in different places(χ^(2)=15.66,P=0.11).Anopheles sinensis(2403)were captured in 22 counties except Anyue County by human tent trap method.Only one Anopheles anthropophilus mosquito was captured in Qingshen County.The average density of Anopheles sinensis was 2.09 mosquitoes/person·hour.From 8 p.m.to 9 p.m.,the highest number of Anopheles sinensis mosquitoes(436)was caught,and the density was 3.79 mosquitoes/person·hour.There was a significant difference in the number of Anopheles sinensis captured in different time periods(F=1751.96,P<0.001).In late June,the largest number of Anopheles sinensis mosquitoes(720)were captured,with a density of 3.13 mosquitoes/person·hour.There were also significant differences in the number of Anopheles sinensis mosquitoes captured in different months(F=2176.56,P<0.001).Dachuan District and Hongya County captured Anopheles sinensis mosquitoes at every time of the month.Conclusions As malaria vectors persist and imported malaria cases occur from time to time in Sichuan Province,it is necessary to continue to strengthen the surveillance of malaria vectors,adopt appropriate methods,comprehensively assess the situation of epidemic sites,take effective vector control measures in a timely manner,and deal with epidemic sites rationally and scientifically,so as to maintain the achievements of malaria elimination and prevent the emergence of imported secondary cases.