Abstract:

Objective To determine the species and density of Japanese encephalitis (JE) vectors and JE infections in the animal host in Huangshi city, Hubei province, providing the basis for development of JE prevention and control measures. Methods From April to October, 2008, mosquito species and density were monitored using the labor hour method, and JE antibody levels in pig serum were measured using the PCR in laboratory. Results The predominant mosquito species in Huangshi was Culex tritaeniorhynchus, followed by Cx. pipiens quinquefasciatus and Anopheles sinensis. Cx. tritaeniorhynchus accounted for 51.99% of the total captured mosquitoes with a density of 3.97/labor-hour. The mosquito density peaked in the second half of June, and remained stable from early July to the end of October. The average positive rate of JE antibody in pig serum was 6.2% with a maximum of 7.2%, which demonstrated an upward trend over time. Conclusion In view of the high density of Cx. tritaeniorhynchus, a vector of JE, in Huangshi, Hubei, and the infection rate among the host animal pigs increasing with the mosquito density, there was a natural environment for the spread of JE.

Key words: Culex tritaeniorhynchus, Japanese encephalitis virus, Host animal, Infection

摘要：

目的 了解湖北省黄石市流行性乙型脑炎(乙脑)传播媒介的种类、密度及动物宿主的乙脑病毒感染状况，为制定乙脑防控措施提供科学依据。方法 于2008年4－10月动态监测蚊虫种类、密度和猪血清乙脑抗体水平；蚊媒监测采用人工小时法，猪血清抗体实验室检测采用PCR。结果 黄石市的优势蚊种为三带喙库蚊，其次是致倦库蚊和中华按蚊；其中三带喙库蚊占捕蚊总数的51.99%，密度为3.97只/人工小时；蚊密度最高峰出现在6月下半月，7月上半月至10月底基本恒定。猪血清乙脑抗体平均阳性率6.2%，最高村阳性率7.2%，随着时间变化呈上升趋势。结论 湖北省黄石市乙脑传播媒介库蚊密度高，宿主动物猪感染率随蚊虫密度增高而变化，存在乙脑传播的自然环境。

关键词: 三带喙库蚊, 乙脑病毒, 宿主动物, 感染