Abstract: This report presented the endemic status of schistosomiasis in the People’s Republic of China at a national level in 2020, and analyzed the data collected from the national schistosomiasis prevention and control system and national schistosomiasis surveillance sites. Among the 12 provinces (municipality and autonomous region) endemic for schistosomiasis in China, Shanghai Municipality, Zhejiang Province, Fujian Province, Guangdong Province and Guangxi Zhuang Autonomous Region continued to consolidate the achievements of schistosomiasis elimination, and Sichuan and Jiangsu provinces maintained the criteria of transmission interruption, while Yunnan, Hubei, Anhui, Jiangxi and Hunan provinces maintained the criteria of transmission control by the end of 2020. A total of 450 counties (cites, districts) were found to be endemic for schistosomiasis in China, with 28 376 endemic villages covering 71 370 400 people at risk of infections. Among the 450 endemic counties (cities, districts), 74.89% (337/450), 21.87% (98/450) and 3.33% (15/450) achieved the criteria of elimination, transmission interruption and transmission control of schistosomiasis, respectively. By the end of 2020, 29 517 cases with advanced schistosomiasis were documented in China. In 2020, 11 117 655 individuals received inquiry examinations and 1 798 580 were positive; 5 263 082 individuals received serological tests and 83 179 were sero⁃positive. A total of 273 712 individuals received stool examinations and 3 were positive, including one case of acute schistosomiasis. In 2020, snail survey was performed in 19 733 endemic villages in China and Oncomelania snails were found in 7 309 villages, accounting for 37.04% of all surveyed villages, with 15 villages identified with emerging snail habitats. Snail survey covered an area of 736 984.13 hm2 and 206 125.22 hm2 snail habitats were found, including 1 174.67 hm2 emerging snail habitats and 1.96 hm2 habitats with infected snails. In 2020, 544 424 bovines were raised in the schistosomiasis⁃endemic areas of China, and 147 887 received serological examinations, with 326 positives detected, while 130 673 bovines received stool examinations, with no positives identified. In 2020, there were 19 214 patients with schistosomiasis receiving praziquantel chemotherapy, and 964 103 person⁃time individuals and 266 280 herd⁃time bovines were given expanded chemotherapy. In 2020, molluscicide treatment was performed in 136 141.92 hm2 snail habitats, and the actual area of chemical treatment was 71 980.22 hm2, while environmental improvements were performed in snail habitats covering an area of 1 464.03 hm2. Data from the national schistosomiasis surveillance sites of China showed that the mean prevalence of Schistosoma japonicum infections were both zero in humans and bovines in 2020, and no S. japonicum infection was detected in snails. The results demonstrate that the overall endemic status of schistosomiasis remains at a low level in China and the goal of the National Thirteenth Five⁃Year Plan for Schistosomiasis Control was achieved as scheduled; however, the endemic situation of schistosomiasis rebounded in local areas. Precision schistosomiasis control and intensified monitoring of the endemic situation and transmission risk of schistosomiasis are required to be performed to facilitate the progress towards elimination of schistosomiasis steadily.

Key words: Schistosomiasis, Endemic situation, Surveillance, China

摘要： 本文通报了2020年全国血吸虫病疫情，并对全国血吸虫病预防控制工作数据和国家血吸虫病监测点疫情监测数据进行了汇总和分析。截至2020年底，全国12个血吸虫病流行省（直辖市、自治区）中，上海、浙江、福建、广东、广西等5个省（直辖市、自治区）继续巩固血吸虫病消除成果，四川、江苏省维持传播阻断标准，云南、湖北、安徽、江西、湖南等5个省维持传播控制标准。全国共有450个血吸虫病流行县（市、区）、28 376个流行村，流行村总人口7 137.04万人；全国450个流行县（市、区）中，337个（74.89%）达到血吸虫病消除标准、98个（21.78%）达到传播阻断标准、15个（3.33%）达到传播控制标准。2020年，全国尚存晚期血吸虫病患者29 517例。2020年，全国共开展询检查病11 117 655人，阳性1 798 580人；开展血检查病5 263 082人，阳性83 179人；开展病原学检查273 712人，阳性3人，其中急性血吸虫病病例1例。2020年，全国共有19 733个流行村开展了钉螺分布调查，7 309个村查出钉螺，占调查总数的37.04%，新查出 15个有螺村；共查螺736 984.13 hm2，查出有螺面积206 125.22 hm2，其中新发现有螺面积1 174.67 hm2，感染性钉螺面积1.96 hm2。2020年，我国血吸虫病流行区现有存栏耕牛544 424头，血检查病147 887头，阳性326头；开展粪检查病130 673头，未发现粪检阳性耕牛。2020年，全国共治疗血吸虫病患者19 214例，扩大化疗964 103人·次；扩大化疗耕牛266 280头·次；开展药物灭螺总面积136 141.92 hm2，实际药物灭螺71 980.22 hm2，环境改造灭螺1 464.03 hm2。2020年全国血吸虫病监测点中，居民和耕牛平均血吸虫感染率均为0，未发现感染性钉螺。疫情数据分析显示，全国血吸虫病呈低度流行水平，全国如期实现《“十三五”全国血吸虫病防治规划》目标，但局部地区疫情有所反弹，仍需开展血吸虫病精准防控、强化血吸虫病疫情及风险监测，在巩固血吸虫病防治成果的基础上稳步推进消除进程。

关键词: 血吸虫病, 疫情, 监测, 中国