四川省广元市2018-2020年登革热媒介伊蚊生态学特征分析

Bionomic characteristics of dengue vector Aedes mosquitoes in Guangyuan of Sichuan province,China,2018-2020

目的了解四川省广元市登革热媒介种类及分布,分析伊蚊属幼蚊和成蚊密度的季节性变化规律,为登革热防制提供建议。方法2018-2020年5-10月中旬,选择广元市利州区为监测点,根据中国疾病预防控制中心《登革热媒介伊蚊监测指南》,开展现场监测工作,严格按照定时、定点、定人的调查方法,采用布雷图指数(BI)法监测伊蚊幼蚊,双层叠帐法监测伊蚊成蚊,使用WPS 2020软件对监测结果进行汇总整理,运用SPSS 16.0软件进行t检验和χ^(2)检验统计分析。BI均数的比较采用t检验,容器指数(CI)和房屋指数(HI)平均率的比较采用χ^(2)检验。结果2018-2020年广元市仅监测到白纹伊蚊。伊蚊幼蚊的平均BI值为25.62,平均CI值为17.91%,平均HI值为14.59%;白纹伊蚊成蚊的平均帐诱指数为0.87只/(顶·h)。每年7、8月为白纹伊蚊幼蚊密度高峰期,成蚊的密度高峰为7月。城市居民区的蚊密度均高于农村(均P<0.001)。不同容器类型中,其他水体的CI值最高,为30.30%;其次为废旧轮胎(28.24%);然后是闲置容器(18.79%)、盆景(16.50%)、明渠(13.68%)、贮水池(12.99%)等;绿化带和竹头石穴监测到积水,但均为阴性。结论广元市存在登革热传播媒介白纹伊蚊,且密度较高,一旦发生登革热病例,存在登革热本地流行的风险。应加强登革热病例的监测预警和蚊虫孳生地环境整治,降低登革热媒介伊蚊密度,以防止登革热疫情暴发流行。

Objective To investigate the species,distribution,and seasonal variation of density of larvae and adult mosquitoes of dengue vector Aedes in Guangyuan of Sichuan province,China,and to provide suggestions for the prevention and control of dengue fever.Methods In the middle ten days from May to October in 2018-2020,Lizhou district of Guangyuan was selected as the surveillance site,and field surveillance was conducted according to Guidelines for dengue vector Aedes surveillance issued by Chinese Center for Disease Control and Prevention,in strict accordance with the investigation method of fixed time,fixed location,and designated personnel.Breteau index(BI)was used to monitor larval Aedes mosquitoes,and the double mosquito net method was used to monitor adult Aedes mosquitoes.WPS2020 software was used to collect surveillance results,and SPSS 16.0 software was used for statistical analysis with the ttest and the Chi-square test.The t-test was used to compare mean BI,and the Chi-square test was used to compare the mean rates of container index(CI)and house index(HI).Results Only Ae.albopictus was found in Guangyuan in 2018-2020.Aedes larvae had a mean BI of 25.62,a mean CI of 17.91%,and a mean HI of 14.59%,and the mean net trap index of adult Ae.albopictus mosquitoes was 0.87 mosquitoes/trap·hour.The peak density of Ae.albopictus larvae was observed in July and August every year,and the peak density of adult Ae.albopictus was observed in July.Urban residential areas had a statistically higher mosquito density than rural area(all P<0.001).Among the different container types,other water bodies had the highest CI of 30.30%,followed by waste tires(28.24%),and idle containers(18.79%),bonsai(16.50%),open channels(13.68%),and storage tanks(12.99%);stagnant water was observed in green belt and bamboo head/stone hole,but without positive results.Conclusion The dengue vector Ae.albopictus is observed in Guangyuan and has a relatively high density.In the event of a case of dengue fever,there is a risk of a local epidemic of dengue fever.It is necessary to strengthen the monitoring and early warning of dengue fever cases,strengthen the environmental improvement of mosquito breeding areas,reduce the density of dengue fever vector Aedes,and prevent the outbreak of dengue fever.