目的: 了解杭州市2017－2021年媒介伊蚊在不同生境下的密度分布及季节消长规律，为有效防控登革热、风险评估和预警提供科学依据。方法: 按照《全国病媒生物监测实施方案》和《浙江省病媒生物监测工作方案》对杭州市15个县（市、区）开展伊蚊监测。成蚊监测采用双层叠帐法，幼蚊监测采用布雷图指数（BI）法，监测时间为4－11月。收集全市15个县（市、区）的蚊虫监测数据，使用Excel 2019软件对监测数据进行汇总分析，计算帐诱指数、BI及容器指数（CI），分类资料比较采用χ²检验，计量资料比较采用单因素方差分析。结果: 2017－2021年杭州市双层叠帐法监测白纹伊蚊密度为2.54只/（顶·h），未捕获到埃及伊蚊。2017年成蚊密度最低，2020年成蚊密度最高，不同年份间帐诱指数蚊密度差异有统计学意义（F=5.117，P=0.017）。季节分布总体呈双峰分布，蚊密度高峰主要在7和10月。2017－2021年平均BI值为9.18，BI高峰期为5－10月，CI显示，各类水体均有白纹伊蚊幼蚊分布，同一年不同水体间幼蚊密度差异均有统计学意义（均P < 0.001），不同年份同一类水体间幼蚊密度差异亦均有统计学意义（均P < 0.001）。结论: 杭州市白纹伊蚊密度较高，存在登革热暴发和区域流行风险，建议各县（市、区）根据蚊虫密度变化、分布及季节消长规律，及时采取蚊虫控制措施。

Objective: To investigate the density distribution of Aedes mosquitoes in different habitats and seasonal fluctuation in Hangzhou, Zhejiang Province, China from 2017 to 2021, so as to provide a scientific basis for effective prevention and control, risk assessment, and early warning of dengue fever. Methods: According to the National Vector Surveillance Implementation Plan and the Zhejiang Provincial Vector Surveillance Plan, Aedes mosquitoes were monitored in 15 districts (counties and cities) in Hangzhou. Adult mosquitoes were monitored using the double-layered mosquito net method, and larvae were monitored using the Breteau index (BI) method. The surveillance time was set during April to November. The mosquito surveillance data of the 15 districts (counties and cities) were collected. Excel 2019 software was used for data analysis. The net trap index, BI, and container index (CI) were calculated. Categorical data were compared using the Chi-squared test. One-way analysis of variance was used for quantitative data. Results: From 2017 to 2021, the density of Ae. albopictus in Hangzhou by the double-layered mosquito net method was 2.54 mosquitoes/net·h, and no Ae. aegypti mosquitoes were captured. The density of adult mosquitoes was lowest in 2017 and highest in 2020. There was a statistical difference in the net trap index between different years (F=5.117, P=0.017). The seasonal distribution generally presented a bimodal pattern, with the peaks of mosquito densities mainly in July and October. The average BI from 2017 to 2021 was 9.18, and the peak period of the BI was during May to October. The CI showed that Ae. albopictus larvae were distributed in all kinds of water bodies. The CI differed statistically between different water bodies in the same year (all P < 0.001) and between different years in the same water body (all P < 0.001). Conclusions: Ae. albopictus density was high in Hangzhou, indicating a risk of dengue fever outbreaks and regional epidemics. It is recommended that the counties (cities, districts) take timely mosquito control measures according to the density, distribution, and seasonal fluctuation of mosquitoes.