Abstract: Objective To investigate the population and density variation of malaria vectors in Zhejiang province, China, and to provide a scientific basis for malaria control strategy in post-elimination stage. Methods From 2012 to 2017, 14 to 18 malaria vector surveillance sites were set up in Zhejiang province. Mosquito population surveillance with the lamp trapping method from sunrise to sunset for 2 days (3 days in 2016-2017) was conducted once in each August. Density surveillance with the overnight human trapping method (usually from19:00 to 07:00) was conducted once in the beginning and late of July, August and September (from May to October in some surveillance sites from 2016 to 2017). All the surveillance spots were set between residential areas and mosquito breeding sites. All Anopheles mosquitoes captured were frozen and dead, and then morphologically identified, counted, and reported. Excel 2013 software was used to analyze the surveillance data. "Dituhui" website was used to draw the surveillance site distribution map online and R 3.5.1 software was used to draw the heat map. Results The results of lamp trapping method for mosquito population surveillance showed that the single vector of malaria transmission in Zhejiang province was Anopheles sinensis. Human trapping density surveillance showed that An. sinensis had been active in some areas in early May, and the density of An. sinensis peaked in late July 3.63 only/(person·h) and dropped to the lowest in late October 0.02 only/(person·h). The peak night activity of An. sinensis in Zhejiang province occurred between 20:00 and 21:00. According to the heat map analysis, although the density of An. sinensis was generally low in late September, the density rebounded in some areas in some years, and the peak time of density had been advanced to May and June at some surveillance sites in the south of Zhejiang province. Conclusion As the single vector of malaria in Zhejiang province, An. sinensis continuously exists, which makes the local transmission of malaria at potential risk. Therefore, continuous and standard vector surveillance needs to be consecutively carried out, and molecular biological technique should be used in the study of mosquito population and insecticide resistance related genes in the future.

Key words: Malaria, Vector surveillance, Anopheles sinensis

摘要： 目的 了解浙江省传疟媒介种群和密度变化规律，为消除后疟疾防控策略提供科学依据。方法 2012-2017年，浙江省共设传疟媒介监测点14~18个，各监测点每年8月开展1次诱蚊灯法（日落到日出连续监测2 d，2016-2017年改为连续3 d）种群监测，每年7-9月（2016、2017年部分监测点扩大为5-10月）上旬和下旬各开展1次通宵人诱法（通常在19：00-07：00进行）密度监测，监测点均选择在居民区与蚊媒孳生地之间。捕获的所有按蚊冷冻处死，经形态学鉴定后计数和上报。使用Excel 2013软件分析监测数据，"地图慧"网站在线绘制监测点分布地图，R 3.5.1软件制作热图。结果 诱蚊灯法监测显示，目前浙江省传疟媒介为单一的中华按蚊。人诱法密度监测显示，5月上旬部分地区已有中华按蚊活动，7月下旬为中华按蚊密度最高峰[3.63只/（人·h）]，10月下旬中华按蚊密度降至最低[0.02只/（人·h）]。浙江省中华按蚊夜间活动高峰出现在20：00-21：00时段。热图分析结果显示，尽管9月下旬中华按蚊密度总体较低，但部分地区部分年份出现密度反弹；浙江省南部个别监测点密度高峰时间已提前至5-6月。结论 浙江省单一传疟媒介中华按蚊持续存在，仍有潜在的本地疟疾传播风险，应继续开展持续、规范的传疟媒介监测，进一步利用分子生物学技术开展按蚊种群和抗性基因研究。

关键词: 疟疾, 媒介监测, 中华按蚊