Abstract: Objective　To investigate the prevalence of human soil⁃transmitted nematode infections in Congjiang County, Guizhou Province in 2023, so as to provide insights into soil⁃transmitted nematodiasis prevention and control in the county. Methods　Congjiang County was divided into 5 areas according to geographical locations, and one township was randomly sampled from each area, followed by one administrative village randomly sampled from each township as the survey site. Two hundred permanent residents without deworming during the past three months were randomly sampled from each survey site using the random cluster sampling method. Participants' fecal samples were collected, soil⁃transmitted nematode eggs were detected using the Kato⁃Katz technique and the prevalence of human soil⁃transmitted nematode infections was compared among participants. Mild, moderate and severe soil⁃transmitted nematode infections were classified according to eggs per gram (EPG), and the proportions of mild, moderate and severe infections were estimated. In addition, participants' family status and household sanitary toilets construction were investigated using questionnaires. Results　A total of 1 001 participants were included at 5 survey sites in Congjiang County, and the overall prevalence of soil⁃transmitted nematode infections was 19.08% (191/1 001). The prevalence rates of Ascaris lumbricoides and hookworm infections were 2.30% (23/1 001) and 1.90% (19/1 001), with all egg⁃positives identified as mild infections, and the prevalence of Enterobius vermicularis infections was 0.10% (1/1 001). The prevalence of Trichuris trichiura infections was 15.78% (158/1 001) among participants, and there was a significant difference in the prevalence among survey villages ([χ2] = 123.345, P < 0.001), with the highest prevalence detected in Liujia Village (39.00%), followed by in Longjiang Village (18.00%). There was an age⁃specific prevalence rate of T. trichiura infections among participants ([χ2] = 166.050, P < 0.001), and the highest prevalence was detected among participants at ages of 10 to 19 years (48.19%), followed by at ages of over 70 years (14.53%) and 50 to 59 years (13.04%). There was an occupation⁃specific prevalence rate of T. trichiura infections among participants ([χ2] = 74.134, P < 0.001), and the highest prevalence was detected among students (32.32%), followed by among workers/migrant workers (10.34%) and farmers (10.12%). There was an educational level⁃specific prevalence rate of T. trichiura infections among participants ([χ2] = 28.761, P < 0.001), and the highest prevalence was detected among participants with an educational level of primary school (21.60%), followed by among illiterate participants (12.03%). There was an ethnicity⁃specific prevalence rate of T. trichiura infections among participants ([χ2] = 42.193, P < 0.001). The proportions of mild, moderate and severe T. trichiura infections were 76.58% (121/158), 14.56% (23/158) and 3.16% (5/158), and all severe infections were identified among primary school students. T. trichiura infections were detected in 123 families, and there were 27 families (21.95%) in which two and more family members were identified with T. trichiura infections. A total of 1 001 valid questionnaires were recovered, and the prevalence rates of T. trichiura infections were 14.69% (139/964) and 34.55% (19/55) in families with and without sanitary toilets ([χ2] = 15.410, P < 0.001). Conclusions　The prevalence of soil⁃transmitted nematode infections was relatively high in Congjiang County, Guizhou Province in 2023, and the T. trichiura infections was notably serious. Intensified soil⁃transmitted nematodiasis control measures are recommended targeting primary school students, middle⁃aged and elderly farmers and migrant workers.

Key words: Soil?transmitted nematode, Trichuris trichiura, Current prevalence, Congjiang County

摘要： 目的　了解2023年贵州省从江县人群土源性线虫感染现状，为该县土源性线虫病防控提供科学依据。方法　将从江县按不同地理方位划分5个片区，各片区分别随机抽取1个乡（镇）的1个行政村作为调查点，每个调查点随机整群抽取200名近3个月未驱虫的常住居民作为调查对象。2023年采集调查对象粪便标本，采用改良加藤厚涂片法（1粪2检）检测虫卵，比较不同特征人群土源性线虫感染状况。根据每克粪便虫卵数（eggs per gram，EPG），将感染状况分为轻、中、重度感染并计算各类感染构成比。此外，采用问卷调查了解调查对象基本情况及家庭无害化厕所建设情况。结果　 从江县5个调查点共调查1 001名调查对象，土源性线虫感染率为19.08%（191/1 001）；其中蛔虫、钩虫感染率分别为2.30%（23/1 001）、1.90%（19/1 001），均为轻度感染；蛲虫感染率为0.10%（1/1 001）；鞭虫感染率为15.78%（158/1 001）。各调查村鞭虫感染率差异有统计学意义（[χ2] = 123.345，P < 0.001），其中留架村鞭虫感染率最高（39.00%），其次为龙江村（18.00%）；各年龄组人群鞭虫感染率差异有统计学意义（[χ2] = 166.050，P < 0.001），其中10～19岁组最高（48.19%），其次是70岁以上组（14.53%）和50～59岁组（13.04%）；各职业人群鞭虫感染率差异有统计学意义（[χ2] = 74.134，P < 0.001），以中学生感染率最高（32.32%），其次是工人（民工）（10.34%）和农民（10.12%）；不同文化程度人群鞭虫感染率差异有统计学意义（[χ2] = 28.761，P < 0.001），以小学文化程度者最高（21.60%），其次为文盲（12.03%）；不同民族人群鞭虫感染率差异有统计学意义（[χ2] = 42.193，P < 0.001）。鞭虫轻、中、重度感染者构成比分别为76.58%（121/158）、14.56%（23/158）和3.16%（5/158），重度感染者均为小学生。在123户家庭中发现鞭虫感染者，其中27户（21.95%）家庭中有2名及以上家庭成员感染。问卷调查共收集有效问卷1 001份，家中是、否建有无害化厕所者鞭虫感染率分别为14.69%（139/964）、34.55%（19/55），差异有统计学意义（[χ2] = 15.410，P < 0.001）。结论　2023年贵州省从江县人群土源性线虫感染率较高，其中鞭虫感染尤为严重，应将小学生、中老年农民、民工作为重点人群开展防控工作。

关键词: 土源性线虫, 鞭虫, 感染现状, 从江县