公共环境治理与蚊媒控制

目的了解山东省淄博市淄川区淡色库蚊(Culex pipiens pallens)病原携带现况。方法在2017—2018年蚊虫活动高峰期采集淄川区淡色库蚊，通过RT-PCR扩增甲病毒属、黄病毒属、布尼亚病毒属和辽宁病毒目标片段及测序，检测蚊虫所携带的病毒种类及数量，利用Excel软件PooledInfRate v4统计程序通过最大似然法估计蚊虫带毒率，利用MEGA7.0软件对所得病毒NS5基因和E基因核酸序列与Genbank中已知库蚊黄病毒参考毒株进行系统发生树构建，分析确定病毒的基因型。结果从3组淡色库蚊(ZCB10_ A22_ 2、ZCB11_ A23_ 2、ZCC2_ A26_ 2)中扩增得到库蚊黄病毒，蚊媒活动高峰期蚊虫带毒率为5.04‰(95%CI：1.35‰~13.78‰)，未检测到甲病毒属、布尼亚病毒属和辽宁病毒。NS5基因系统发育分析发现3组病毒与分离自上海的病毒株(MG602497.1)遗传关系最近，相似度为96.83%~97.23%；E基因系统发育分析发现3组病毒与分离自日本东京的病毒株(AB262759.2、AB377213.1)遗传关系最近，相似度为97.55%~97.72%。病毒分型为Ⅰ型库蚊黄病毒。结论淄川区淡色库蚊携带库蚊黄病毒，应持续开展蚊虫携带病原体监测。

Present and future arboviral threats

ObjectiveTo investigate the pathogens carried by Culex pipiens pallens in Zichuan district.MethodsCx.pipiens pallens were collected in Zichuan District during the peak period of mosquito vector activity from 2017 to 2018.The presence of ISFVs, Bunyavirus, Alphavirus and Liaoningvirus were tested using RT-PCR-based assay, followed by the sequencing of PCR products to detect the type and number of viruses carried by mosquitoes.The virus infection rates of mosquitoes were calculated by Bias-corrected maximum likelihood estimation (MLE) using the Excel add-in PooledInfRate v4 statistical software package.MEGA 7.0 software was used to construct phylogenetic tree between the nucleic acid sequences of the obtained virus NS5 gene and E gene and the known reference strains of CxFV in GenBank to determine the genotype of the virus.ResultsCxFV was amplified from three groups (ZCB10_ A22_ 2、ZCB11_ A23_ 2、ZCC2_ A26_ 2).The overall MLE values (and 95% confidence interval) for CxFV of peak period of mospuito vector activity was 5.04 (1.35－13.78) per 1 000.No other viruses were detected.Phylogenetic analysis of NS5 gene showed that the genetic relationship between the three groups of virus and the virus strain (MG602497.1) isolated from Shanghai was the closest, with the similarity of 96.83%－97.23%.And phylogenetic analysis of E gene showed that the genetic relationship between the three groups of viruses and the virus strains (AB262759.2, AB377213.1) isolated from Tokyo, Japan was the closest, with the similarity of 97.55%－97.72%.The virus was identified as CxFV and genotype Ⅰ.ConclusionCx.pipiens pallens carries CxFV in Zichuan district. It is imperative to carry out continuously surveillance of mosquito carryied pathogens.