Objective: To analyze the endemic status of schistosomiasis in Suzhou City from 2010 to 2020, so as to provide the evidence for formulating the future schistosomiasis control strategy.
Methods: The data pertaining to the endemic status of schistosomiasis in Suzhou City from 2010 to 2020 were retrieved from the annual schistosomiasis control report, the information management platform of schistosomiasis (parasitic diseases) in Jiangsu Province and the Parasitic Diseases Control Information Management System of Chinese Center for Disease Control and Prevention, including snail survey data, snail control data and schistosomiasis examination data, and were retrospectively reviewed. Differences of proportions were tested for statistical significance with chi-square test, and the trends in proportions were evaluated using the chi-square test for trends.
Results: Elimination of schistosomiasis was achieved in Suzhou City in 2018, and there were 3.528 9 million residents living in schistosomiasis-endemic villages of 81 townships in 9 counties. A total of 707 600 labor-days were used for snail survey in 11 586 village-times in Suzhou City from 2010 to 2020, covering 18 572.73 hm2, and snail habitats were detected with an area of 68.61 hm2, including emerging snail habitats of 37.30 hm2. A total of 23 144 snails were dissected, and no Schistosoma japonicum infection was detected. Reemerging and emerging snail habitats were predominantly found in inlands. During the period from 2010 to 2020, snail control was performed in Suzhou City for 71 000 labor-times, and snail control was done covering 269.34 hm2 through chemical treatment and covering 3.48 hm2 through environmental improvements. A total of 674 002 person-times received serological tests for S. japonicum infections in Suzhou City from 2010 to 2020, with seroprevalence of 0.38%, and a total of 33 835 person-times received stool examinations, with no egg-positives identified. The sero-prevalence of S. japonicum infections appeared an overall tendency towards a rise in Suzhou City from 2010 to 2020 (χ2 = 129.48, P < 0.001). The sero-prevalence of S. japonicum infections appeared high among local residents in 2016, and remained stable in other years, while the sero-prevalence of S. japonicum infections appeared an overall tendency towards a rise among mobile populations (χ2 = 54.11, P < 0.001). There were 278 800 and 175 202 serological tests among local residents and mobile populations in Suzhou City from 2013 to 2020, and 0.50% and 0.35% sero-prevalence rates were detected, respectively. The sero-prevalence of S. japonicum infections was significantly higher among local residents than among mobile populations in Suzhou City (χ2= 54.76, P < 0.001).
Conclusions: There is a risk of rebound of schistosomiasis in Suzhou City. Integrated control should be reinforced to prevent the risk of rebound of schistosomiasis in Suzhou City.
［摘要］ 目的 分析 2010—2020 年苏州市血吸虫病疫情, 为制定巩固血吸虫病消除策略提供依据。方法 从 2010—2020 年苏州市血吸虫病防治工作报表、江苏省血吸虫病 (寄生虫病) 防治信息管理平台及中国疾病预防控制寄生虫病防 治信息管理系统中收集历年苏州市查螺、灭螺、血吸虫病查病等资料, 采用回顾性研究方法进行研究, 本地人群和流动人 群血吸虫病血检阳性率比较采用 χ2 检验, 历年血检阳性率比较采用趋势性 χ2 检验。结果 苏州市于 2018 年通过江苏省 血吸虫病消除评估考核。2010—2020 年累计查螺 18 572.73 hm2, 共查出有螺面积 68.61 hm2, 其中新发现钉螺面积 37.30 hm2; 共解剖钉螺 23 144 只, 未发现感染性钉螺; 无论是复现还是新发钉螺环境, 均以内陆为主。2010—2020 年累计药物灭螺 269.34 hm2, 其中环境改造灭螺 3.48 hm2。2010—2020 年共对 674 002 人·次进行血吸虫病血清学检查, 检出阳性 2 567 人·次, 血检阳性率 0.38%; 病原学检查 33 835 人·次, 未检出阳性。2010—2020 年血吸虫病血检阳性率总体呈上升趋势 (χ2 = 129.48, P < 0.001), 其中本地人群血检阳性率除 2016 年居于高位外, 其余几年相对平稳; 流动人口血检阳性率总体 呈上升趋势 (χ2 = 54.11, P < 0.001)。2013—2020 年分别对本地人群和流动人口开展血吸虫病血清学检查 278 800、175 202 人·次, 分别检出阳性 1 387、609 人·次, 阳性率分别为 0.50%和0.35%, 本地人群血检阳性率高于流动人口 (χ2 = 54.76, P < 0.001)。结论 苏州市血吸虫病疫情有回升风险, 应继续采取综合防控措施降低血吸虫病疫情复燃的风险。.
Keywords: Endemic situation; Schistosomiasis; Suzhou City.