Abstract: Objective To investigate the densities of Culex tritaeniorhynchus in surrounding areas of Beijing Capital International Airport during 2011 to 2013, and to provide a scientific basis for the control and prevention of Japanese encephalitis (JE). Methods Seven monitoring stations within 2000 meters around Beijing Capital International Airport were included in this study. Carbon dioxide light traps were used to capture mosquitoes according to GB/T 23797-2009. Descriptive epidemiological analysis was performed with mosquito density monitoring data from 2011 to 2013 in surrounding areas of Beijing Capital International Airport. Analysis of variance was used in comparison of mosquito density. The correlation analysis between incidence of JE and density of Cx. tritaeniorhynchuswas carried out by Pearson correlation coefficient.Results A total of 88 789 adult mosquitoes were captured within the 3 years of investigation.Cx. pipiens pallenswas the predominant mosquito species (accounting for 80.54% of all captured mosquitoes), followed by Cx. tritaeniorhynchus(18.89% ). The annual average density indices ofCx. tritaeniorhynchusin the 3 years were 4.31, 1.62, and 13.01 mosquitoes per light-hour, respectively, without significant differences between them (F＝1.579,P＞0.05). AdultCx. tritaeniorhynchuswas only captured between August and October during the 3 years. The monthly average densities were 1.04, 32.00, and 1.15 mosquitoesper light-hour, respectively,with significant differences between them (F＝5.831, P＜0.01). The density of Cx. tritaeniorhynchusin September was significantly higher than those in August and in October, and the highest density appeared at mid-September. Adult Cx. tritaeniorhynchuswas captured in all seven monitoring stations, with densities ranging from 0.44 to 41.09 mosquitoes per light-per hour.Cx. tritaeniorhynchusdensity was the lowest in residential area and the highest around the Wenyu river system. No significant difference was found between seven monitoring stations (F＝1.368,P＞0.05). In the 3 years, only 3 JE cases were reported from September to October in 2013, from Shunyi district, where Beijing Capital International Airport was located. Apositive correlation was found between the incidence of JE and the density ofCx. tritaeniorhynchus(rs＝0.898,P＝0.015).Conclusion The density and constituent ratio ofCx. tritaeniorhynchuswere high in surrounding areas of Beijing Capital International Airport. Cx. tritaeniorhynchusmainly inhabited outdoor environments such as riverside. The activity peakof Cx. tritaeniorhynchuswas between August and September, which coincided with the epidemic period of JE. The density of Cx. tritaeniorhynchuswas positively correlated with the incidence of JE. Therefore, surveillance ofCx. tritaeniorhynchusshould be strengthened.

Key words: Culex tritaeniorhynchus, Surveillance, Epidemiological analysis

摘要： 目的 了解2011－2013年首都国际机场周边三带喙库蚊密度分布情况,为流行性乙型脑炎(乙脑)防控提供科学依据。方法 在机场周边2000 m范围内选取7个监测点,采用国家标准GB/T 23797－2009中的二氧化碳诱蚊灯法,通过描述性研究方法对首都机场周边2011－2013年三带喙库蚊监测数据进行流行病学分析;蚊密度数据比较采用方差分析;使用Pearson秩相关对2013年5－10月三带喙库蚊密度与乙脑发病进行相关分析。结果 3年来共捕获成蚊88 789只,淡色库蚊为优势蚊种,占捕获总数的80.54%,三带喙库蚊占18.89%;2011－2013年三带喙库蚊年平均密度指数分别为4.31、1.62和13.01只/ (灯·h),差异无统计学意义(F＝1.579,P＞0.05);3年来,仅8－10月能够捕获三带喙库蚊,月平均密度分别为1.04、32.00和1.15只/ (灯·h),差异有统计学意义(F＝5.831,P＜0.01);9月三带喙库蚊密度明显高于8月和10月,其中9月中旬密度最高;7个监测点均有三带喙库蚊捕获,密度在0.44～41.09只/ (灯·h)之间,其中居民区密度最低,温榆河水系密度最高,7个监测点三带喙库蚊密度差异无统计学意义(F＝1.368,P＞0.05)。3年来,仅2013年9－10月首都机场所在地顺义区报告3例乙脑病例,三带喙库蚊密度与乙脑发病呈正相关关系(rs＝0.898,P＝0.015)。结论 首都机场周边三带喙库蚊构成及密度水平均较高,河边等野外环境是其栖息的主要场所,蚊虫活动高峰时间(8－9月)与乙脑疫情的发生时间相一致,蚊密度与乙脑发病呈正相关,应加强对三带喙库蚊的监测工作。

关键词: 三带喙库蚊, 监测, 流行病学分析