Abstract: Objective To investigate the distribution of malaria vectors Anopheles after the elimination of malaria in 12 counties and cities in Dali Bai autonomous prefecture (Dali prefecture), Yunnan province, China; to assess the local risk of imported malaria retransmission, and to provide a basis for consolidating local achievements of malaria elimination and formulating local technical schemes for preventing imported malaria retransmission after elimination of malaria. Methods The study was conducted from July to September in 2017. According to the altitude, each county (city) was divided into high, middle, and low stratifications, and one natural village from each stratification was selected as the survey site. The all-night light trapping method and half-night human-bait method were used. One barn or human room in the east, west, south, north, and middle of each survey site was selected as an observation point. The all-night light trapping method was used to catch mosquitoes at each survey site for 3 consecutive nights per month, and the half-night human-bait method was used to catch mosquitoes at each low-altitude survey site once a month. Results A total of 13 species of Anopheles mosquitoes were captured, among which An. sinensis was distributed in all these 12 counties and cities; An. minimus was only caught in Yunlong county; An. kunmingensis was distributed in 7 counties and cities, i.e., Xiangyun county, Jianchuan county, Binchuan county, Heqing county, Eryuan county, Weishan county, and Dali city. The results of all-night light trapping method showed that Xiangyun county had the highest density of Anopheles mosquitoes (164.55 mosquitoes/light·night). The results of half-night human-bait method showed that only Jianchuan county and Heqing county had Anopheles mosquitoes caught, and the densities were 0.72 mosquitoes/net·h and 0.06 mosquitoes/net·h, respectively. Conclusion Considering the imported malaria cases in 2018-2020, Dali city is at risk of retransmission of Plasmodium vivax; Yunlong county is potentially at risk of retransmission of multiple malaria; the other 10 counties are all potentially at risk of retransmission of P. vivax. It is suggested that related departments should keep strengthening the team building for malaria control and the surveillance work of malaria vectors Anopheles.

Key words: Malaria, Anopheles vectors, Dali Bai autonomous prefecture

摘要： 目的 掌握大理白族自治州（大理州）12个县（市）消除疟疾后传疟媒介按蚊分布情况，评估当地疟疾输入再传播风险，为巩固当地消除疟疾成果和制定当地消除疟疾后防止输入再传播技术方案提供依据。方法 2017年7－9月，将每县海拔分为高、中和低3层，每层选1个自然村为调查点；采用全通宵诱蚊灯捕蚊法和半通宵人诱捕蚊法，在每个调查点的东、西、南、北、中各选取1间畜房或人房为观察点，每月每个调查点连续3晚进行全通宵诱蚊灯捕蚊，同时在低海拔调查点每月开展1晚半通宵人诱捕蚊。结果 2017年7－9月共捕获按蚊13种，其中中华按蚊在12个县（市）均有分布，微小按蚊仅在云龙县捕获，昆明按蚊在祥云、剑川、宾川、鹤庆、洱源、巍山和大理7个县（市）有分布。全通宵诱蚊灯捕蚊法揭示，按蚊密度最高的是祥云县，为164.55只/（灯·夜）；半通宵人诱捕蚊法揭示，仅在剑川和鹤庆县捕获到按蚊种类，密度分别为0.72和0.06只/（顶·h）。结论 结合2018－2020年疟疾输入病例疫情，大理市属于间日疟再传播风险市，云龙县为潜在多种疟疾再传播风险县，其他10个县均为潜在间日疟再传播风险县，建议相关部门继续加强疟疾防控人员队伍建设和传疟媒介按蚊监测工作。

关键词: 疟疾, 媒介按蚊, 大理白族自治州