目的 分析2020—2022年全国血吸虫病监测点流动人群的血清流行病学特征和血清抗血吸虫抗体阳性者的流向构成，为制定流动人群血吸虫病监测方案提供科学依据。 方法 收集中国传染病预防控制信息系统、寄生虫病防治信息管理系统中2020—2022年全国血吸虫病流动人群监测数据和流动人群血吸虫病病例个案流行病学调查数据，包括性别、年龄、职业和户籍地所在县等人口社会学特征信息、迁出地或迁入地等人口流动信息以及血吸虫病血清学和病原学检测结果。采用描述性流行病学分析流动人口的血清抗体水平的三间分布特征，采用卡方检验分析不同性别、年龄、职业组之间血清抗体阳性率的差异，采用χ²分割法进行多组阳性率的两两比较，使用桑基图描述血清抗体阳性者的流向。 结果 2020—2022年，13个省（自治区、直辖市）455个监测县共检测6岁及以上流动人群302 460人次，1 199人次血清抗体检测结果为阳性，1人粪检结果为阳性。2020—2022年流动人群血清抗体阳性率依次为0.47%（450/96 596）、0.44%（442/101 558）、0.29%（307/104 306），2020与2021年均高于2022年（χ² = 39.310、28.178，均P < 0.01）。2020—2022年，江西的血清抗体阳性率均为最高，分别为1.24%（91/7 316）、1.33%（112/8 412）和0.65%（56/8 648）；男性和女性血清抗体阳性率分别为0.48%（277/57 550）、0.44%（173/39 046），0.44%（260/59 458）、0.43%（182/42 100），0.31%（191/62 237）、0.28%（116/42 069），各年度不同性别间差异均无统计学意义（χ² = 0.734、0.014、0.830，均P > 0.05）；农民、渔船民、其他职业组血清抗体阳性率分别为0.82%（225/27 561）、0.86%（20/2 333）、0.31%（205/66 702），0.78%（226/28 928）、0.75%（16/2 141）、0.28%（200/70 489），0.53%（158/29 661）、0.91%（23/2 523）、0.17%（126/72 122），农民组与渔船民组的血清抗体阳性率均高于其他职业组（χ² = 111.287、118.991、96.799，20.985、15.060、66.450；均P < 0.01）。2020—2022年6~15岁组的血清抗体阳性率分别为最高（1.00%，16/1 597）、次高（0.70%，10/1 436）和最低（0.05%，1/1 836），各年度不同年龄组的差异均有统计学意义（χ² = 41.282、56.515、54.425，均P < 0.01）。在填写完整迁移地区信息的血清抗体阳性者中，迁出地占比居前的依次为四川（21.86%，256/1 171）、江西（21.18%，248/1 171）和湖北（18.02%，211/1 171），迁入地占比居前的为江西（18.87%，221/1 171）和四川（18.87%，221/1 171）；在血吸虫病未消除省省内或省际流动的占73.87%（865/1 171），在未消除省份和消除省份之间流动占19.98%（234/1 171）；有46名血清抗体阳性者是从非流行区迁入流行区。 结论 2020—2022年我国血吸虫病监测点流动人群血吸虫病疫情保持在极低水平，但需要加强对江西等地区、低年龄人群以及与未消除地区之间流动人群的监测和对既往感染者的管理。

Objective To analyze the seroepidemiological characteristics in transient population and the moving direction of the individuals with positive serum anti-schistosome antibody at national schistosomiasis surveillance sites of China during 2020-2022, and to provide a scientific basis for formulating surveillance program for schistosomiasis in the transient population. Methods Data of the national population-based schistosomiasis surveillance and individual cases recorded from transient population during 2020-2022 were collected from the Information System for Infectious Diseases Prevention and Control and the Information System for Parasitic Disease Prevention and Control. The data include demographic characteristics of sex, age, occupation and the counties of residence registered, and the people migrating information regarding the locations of moving in or moving out from, as well as the results of serological and pathogenic examinations for schistosomiasis. Descriptive epidemiological methods were employed to analyze the spatial, temporal, and demographic distribution of the serum anti-schistosome level among the transient population. Chi-square analysis was used to compare the differences in the positive rates of serum antibodies among the groups of sex, age, and occupation. Partitions of χ² method was used for multiple comparisons of the positive rates. Sankey diagram was used to describe the moving direction of the individuals with positives serum antibodies. Results A total of 302 460 person-time among the transient population was surveyed from 455 surveillance counties in 13 provinces (or autonomous regions or municipalities) in China from 2020 to 2022, and 1 199 was found positive with serum antibodies, and one was positive with fecal examination. During 2020-2022, the positive rates of serum antibodies among the transient population were 0.47% (450/96 596), 0.44% (442/101 558), and 0.29% (307/104 306), respectively. The rates in 2020 and 2021 were both higher than the rate in 2022 (χ² = 39.310, 28.178; both P < 0.01). During 2020-2022, the highest positive rates of serum antibodies were detected in Jiangxi, showing 1.24% (91/7 316), 1.33% (112/8 412), and 0.65% (56/8 648), respectively. The positive rates of serum antibodies were 0.48% (277/57 550), 0.44% (260/59 458), and 0.31% (191/62 237) in males and 0.44% (173/39 046), 0.43% (182/42 100), and 0.28% (116/42 069) in females, respectively. No statistically significant differences were observed between sex groups in each year (χ² = 0.734, 0.014, 0.830; all P > 0.05). The positive rates of serum antibodies were 0.82% (225/27 561), 0.78% (226/28 928) and 0.53% (158/29 661) in farmers, 0.86% (20/2 333), 0.75% (16/2 141) and 0.91% (23/2 523) in boatmen/fishermen, and 0.31% (205/66 702), 0.28% (200/70 489) and 0.17% (126/72 122) in other occupation group, respectively. The positive rates of serum antibodies were higher in the farmers and boatmen/fishermen groups compared to the other occupation group (χ² = 111.287, 118.991, 96.799; 20.985, 15.060, 66.450; all P < 0.01). The positive rates of serum antibodies in group of 6-15 years were the highest (1.00%, 16/1 597) in 2020, the second highest (0.70%, 10/1 436) in 2021, and the lowest (0.05%, 1/1 836) in 2022, respectively. The differences among different age groups were statistically significant for each year (χ² = 41.282, 56.515, 54.425; all P < 0.01). Among the seropositive individuals who provided complete information on their migration regions, higher proportions of emigration location were seen from Sichuan (21.86%, 256/1 171), Jiangxi (21.18%, 248/1 171), and Hubei (18.02%，211/1 171), and the highest two destinations were Jiangxi (18.87%, 221/1 171) and Sichuan (18.87%, 221/1 171). Among the seropositive individuals who provided complete migration information, higher proportions of emigration location were seen from Sichuan (21.86%, 256/1 171), Jiangxi (21.18%, 248/1 171), and Hubei (18.02%, 211/1 171). The higher proportions of immigration location were seen in Jiangxi (18.87%, 221/1 171) and Sichuan (18.87%, 221/1 171); the proportion of immigration location within or between non-eliminated provinces was 73.87% (865/1 171), and the proportion of migrants moving between non-eliminated and eliminated provinces was 19.98% (234/1 171). Forty-six individuals with positive serum antibodies migrated from non-endemic areas to endemic areas. Conclusion According to the survey of the national surveillance sites, the prevalence of schistosomiasis in transient population in China remained at a very low level from 2020 to 2022. It is imperative to strengthen the surveillance for the transient population in Jiangxi, younger age group and the migrants moving in or out from non-elimination areas, as well as the proper management of people with past infections.