目的 分析安徽省国家血吸虫病监测点疫情变化，为推进全省血吸虫病消除策略提供科学依据。方法 根据《全国血吸虫病监测方案（2020版）》要求，在安徽省50个流行县（市、区）设立国家血吸虫病监测点，于2020—2024年10—11月对Ⅰ类监测县的监测村内6岁以上常住居民开展本地人群监测，每村不少于300人；采用主动监测与哨点医院被动监测相结合的方式进行血吸虫病筛查流动人群，每县不少于200人。采用间接血凝试验进行血吸虫病血清学筛查，阳性者采用尼龙绢袋集卵孵化法（一粪三检）和改良加藤厚涂片法（Kato-Katz，一粪三检）开展病原学检查。每年10—12月采用毛蚴孵化法对家畜血吸虫感染情况进行检测。每年春季采取系统抽样结合环境抽查法调查钉螺分布情况，压碎镜检法检测钉螺血吸虫感染情况，对Ⅰ类监测县和Ⅱ类监测县中近5年内达到传播阻断标准的有螺县加以环介导等温扩增（LAMP）技术检测钉螺血吸虫核酸情况。每年春季在Ⅰ类监测县和部分Ⅱ类监测县部分行政村有螺环境进行野粪及钉螺分布情况监测。结果 2020—2024年，安徽省累计开展本地人群血吸虫病血清学筛查63 868人次，检出阳性908人次（男性530人、女性378人），血检阳性率从2020年的1.49%（263/17 644）下降至2024年的1.23%（118/9 592）；累计开展流动人群血吸虫病血清学筛查55 587人次，检出阳性104人次（男性71人、女性33人），血检阳性率从2020年的0.41%（43/10 596）下降至2024年的0.07%（8/10 889）；本地人群与流动人群均未发现粪检阳性患者。累计检测各类家畜5 812头，均未发现血吸虫感染。2020—2024年，累计调查环境7 810个，累计面积593.85 km²，发现有螺面积由2020年的37.80 km²下降至2024年的34.90 km²；系统抽样设框累计调查1 101 819框，5年有螺框平均出现率为8.51%，活螺平均密度为0.30只/0.11 m²。各年有螺框出现率最高的流行类型分别为沟渠、旱地、沟渠、沟渠、沟渠，出现率分别为12.16%（8 174/67 209）、16.57%（489/2 952）、13.55%（7 455/55 019）、10.13%（5 198/51 316）、10.19%（6 669/65 441），各年度不同流行类型有螺框出现率差异有统计学意义（χ² = 2 012.52、3 174.12、5 501.59、1 454.46、720.04，均P < 0.01）。2020—2024年山丘型流行类型（11.32%、10.55%、10.19%、10.68%和9.48%）的有螺框出现率均高于湖沼型（7.72%、9.60%、7.91%、7.17%和7.63%）（χ² = 740.27、35.61、216.66、433.64、151.03，均P < 0.01）。中间宿主监测及风险监测中均未发现血吸虫感染性钉螺，野粪调查中仅在2022年检出1份牛粪血吸虫感染阳性，其余均未检测出血吸虫感染阳性。结论 2020—2024年安徽省血吸虫病疫情总体呈下降趋势，但其传播风险依然存在，今后应进一步完善和加强血吸虫病监测体系建设，为精准实施血吸虫病的防治策略提供科学依据。

Objective To investigate the changes in the endemic situation of schistosomiasis in national surveillance sites of Anhui Province, so as to provide the scientific evidence for promoting the schistosomiasis elimination strategy in the provinc. Methods According to the requirements of the National Schistosomiasis Surveillance Scheme in China (2020 Edition), national schistosomiasis surveillance were assigned in 50 endemic counties (cities, districts) across Anhui Province. During the period between October and November from 2020 to 2024, schistosomiasis surveillance was performed among permanent residents at ages of over 6 years in surveillance villages from class I surveillance counties, with no less than 300 residents in each village, and schistosomiasis screening was conducted among mobile populations by means of active surveillance and sentinel hospitals-based passive surveillance, with no less than 200 populations in each county. Serological screening of schistosomiasis was performed using indirect hemagglutination test, and sero-positive individuals were subjected to parasitological examinations using egg hatching tests with nylon gauzes (three slides for one sample) and modified Kato-Katz thick smear technique (three slides for one sample). During the period between October and December from 2020 to 2024, Schistosoma japonicum infection was detected in livestock using the miracidium hatching test. Oncomelania hupensis snail distribution was surveyed using systematic sampling combined with environmental sampling in each spring from 2020 to 2024, and S. japonicum infection was detected in O. hupensis snails using microscopy. S. japonicum nucleic acid was detected in O. hupensis snails using loop-mediated isothermal amplification (LAMP) assay in class Ⅰ and Ⅱ surveillance counties where the transmission of schistosomiasis was achieved during the recent 5 years, and the surveillance of wild feces and snail distribution was performed in snail-infested habitats in some administrative villages in class Ⅰ surveillance counties and some class Ⅱ surveillance counties in each spring from 2020 to 2024. Results Serological screening for schistosomiasis was conducted among local residents at 63 868 person-times in Anhui Province from 2020 to 2024, and there were 908 sero-positives detected (530 males and 378 females). The seroprevalence of schistosomiasis reduced from 1.49% (263/17 644) in 2020 to 1.23% (118/9 592) among local residents in 2024. Serological screening for schistosomiasis was conducted among mobile populations at 55 587 person-times in Anhui Province from 2020 to 2024, with 104 sero-positive cases detected (71 males and 33 females), with a reduction from 0.41% (43/10 596) in 2020 to 0.07% (8/10 889) in 2024. Nevertheless, no egg-positives were identified among local residents or mobile populations. A total of 5 812 livestock were tested for S. japonicum infections, with no infections identified. A total of 7 810 settings were surveyed for snail distribution from 2020 to 2024, covering an area of 593.85 km², and the area with snail habitats reduced from 37.80 km² in 2020 to 34.90 km² in 2024. A total of 1 101 819 frames were surveyed for snails using a systematic sampling method, and the 5-year mean occurrence of frames with snails and density of living snails were 8.51% and 0.30 snails per 0.11 m², respectively. The highest occurrence of frames with snails was seen in ditches (12.16%, 8 174/672 091), dry lands (6.57%, 489/2 952), ditches (13.55%, 7 455/55 019), ditches (10.13%, 5 198/51 316), and ditches (10.19%, 6 669/65 441) from 2020 to 2024, respectively, and there were significant differences in the occurrence of frames with snails in different types of endemic areas from 2020 to 2024 (χ² = 2 012.52, 3 174.12, 5 501.59, 1 454.46, 720.04; all P < 0.01). The occurrence rates of frames with snails were higher in the hilly endemic areas (11.32%, 10.55%, 10.19%, 10.68%, and 9.48%) than in marshland and lake endemic areas (7.72%, 9.60%, 7.91%, 7.17%, and 7.63%) from 2020 to 2024 (χ² = 740.27, 35.61, 216.66, 433.64, 151.03; all P < 0.01). No S. japonicum infections were identified in snails during the intermediate host monitoring or risk monitoring, and S. japonicum infection was detected in only one wild bovine stool sample in 2022, with no S. japonicum infections identified in other wild stool samples. Conclusion The prevalence of schistosomiasis appeared an overall tendency towards a decline in Anhui Province from 2020 to 2024; however, there was still a risk of schistosomiasis transmission. Improved and intensified construction of the schistosomiasis surveillance system is recommended to provide insights into implementation of the precise schistosomiasis control strategy.