Abstract: Objective To investigate the status of mosquitoes carrying Japanese encephalitis (JE) virus in some parts of Tianjin, providing the basis for the control and prevention of JE. Methods The light trap method was used to collect mosquitoes twice a month from July 2010 to September 2010 in Tianjin. Reverse transcription-polymerase chain reaction (RT-PCR) detection was done and the amplified target fragments were sequenced. The evolutionary tree was built with the Mega 4.0 software by the O-linked method. Results A total of 10 285 adult mosquitoes, which belonged to 2 generaes and 3 species (Culex pipiens pallens, Cx. tritaeniorhynchus, and Anopheles sinensis) were captured. Molecular identification showed that the Cx. pipiens pallens was infected with JE viruses, identified by genotyping as JE virus typeⅠand named TJ01 (HQ718463). Conclusion There exists mosquito infection with JE virus typeⅠin Tianjin, which is close to the JE viruses isolated in Shanghai in terms of their evolution.

Key words: Mosquito, Japanese encephalitis virus, Sequence analysis

摘要： 目的 调查天津市部分地区蚊虫携带流行性乙型脑炎(乙脑)病毒状况,为乙脑防治提供依据。方法 2010年7－9月,使用灯诱法,每月在天津市5个区(县)采集蚊虫2次,用RT-PCR检测乙脑病毒核酸;扩增的目标片段进行序列测定;用Mega 4.0软件以邻位相连法构建进化树。结果 共捕获成蚊10 285只,2属3种(淡色库蚊、三带喙库蚊、中华按蚊),一组淡色库蚊样品,经分子生物学鉴定呈乙脑病毒感染阳性,命名为TJ01(HQ718463),基因分型为Ⅰ型乙脑病毒。结论 天津市蚊虫中存在基因Ⅰ型乙脑病毒感染,与上海市乙脑病毒分离株进化关系较近。

关键词: 蚊虫, 乙型脑炎病毒, 序列分析