OBJECTIVE: To investigate the family aggregation of human hookworm infections in Sichuan Province and to identify its influencing factors, so as to provide insights into management of hookworm infections.
METHODS: Three to four counties (districts) were sampled from basins, hilly regions and mountainous regions around the basins in Sichuan Province from 2017 to 2022 as fixed survey sites, and 17 to 30 counties (districts) were selected as mobile survey sites. At least 1 000 permanent residents at ages of 3 years and older were sampled from each survey site, and hookworm eggs were detected in human stool samples using the Kato-Katz technique. Subjects with 2 and more family members and at least 2 individuals diagnosed with hookworm infections in the county (district) where they lived were selected, and the familial aggregation of hookworm infections was analyzed using the test of goodness of fit for binomial distribution. In addition, the knowledge and practice of hookworm disease control were investigated among residents in Hejiang County and Wutongqiao District, Leshan City, Sichuan Province in 2021 and 2022, and the difference in the knowledge and practice of hookworm disease control was compared between members with and without familial aggregation of hookworm infections.
RESULTS: A total of 66 812 residents from 25 196 households were sampled from main endemic areas of hookworm diseases in Sichuan Province from 2017 to 2022 for detection of hookworm infections, and 4 403 infections were identified (6.59% prevalence). The distribution of human hookworm infections in Sichuan Province did not fit the binomial distribution, and showed family aggregations (χ2 = 2 116.759, P < 0.001). Family aggregation of human hookworm infections was found in endemic areas with 1% and higher prevalence of human hookworm infections (χ2 = 136.006 to 428.738, all P values < 0.001), and family aggregation of human hookworm infections was identified in different years (χ2 = 87.615 to 471.838, all P values < 0.001) and in different terrains of endemic areas (χ2 = 8.423 to 1 144.176, all P values < 0.001). The members with hookworm infections had median eggs per gram of 180 (interquartile range, 780) in aggregated families and 72 (102) in non-aggregated families (Z = -2.686, P < 0.05). The proportion of members in families with aggregation of hookworm infections who knew the preventive measures of hookworm disease was significantly lower than in non-aggregated families (24.49% vs. 51.72%; χ2 = 10.262, P < 0.05), and the proportion of members in families with aggregation of hookworm infections who often worked barefoot on the ground was significantly higher than in non-aggregated families (30.61% vs. 13.25%; χ2 = 6.289, P < 0.05).
CONCLUSIONS: There is a familial aggregation of human hookworm infections in Sichuan Province, and awareness of preventive measures for hookworm disease and frequent working barefoot on the ground are associated with familial aggregation of hookworm infections.
[摘要] 目的 调查四川省人群钩虫感染家庭聚集性, 探讨其影响因素, 为科学防治钩虫病提供参考。方法 2017—2022年, 于四川省盆地、丘陵地区、盆周山区等钩虫病主要流行区选取3 ~ 4个县 (区) 作为人群钩虫感染固定调查点, 并 选取17 ~ 30个县 (市、区) 作为流动调查点。每个调查点抽取至少1 000名≥ 3周岁的常住居民作为调查对象, 采用Kato-Katz法进行粪便钩虫虫卵检测。选取家庭人口数≥ 2人、且所在县 (区) 当年钩虫感染人数≥ 2人的调查对象, 应用二项 分布拟合优度检验进行钩虫感染家庭聚集性分析。2021—2022年在四川省合江县和乐山市五通桥区开展人群钩虫病 防治知识与相关行为调查, 比较两地钩虫感染聚集性家庭与非聚集性家庭成员钩虫病防治知识与相关行为差异。结果 2017—2022年, 在四川省钩虫病主要流行区共抽取25 196户家庭的66 812名居民进行钩虫感染调查, 发现钩虫感染 4 403例, 感染率为6.59%。四川省主要流行区人群钩虫感染分布不符合二项分布, 具有家庭聚集性 (χ2 = 2 116.759, P < 0.001); 人群钩虫感染率≥ 1%的流行区均发现钩虫感染具有家庭聚集性 (χ2 = 136.006 ~ 428.738, P 均< 0.001); 不同年份 (χ2 = 87.615 ~ 471.838, P 均< 0.001) 、不同地形流行区 (χ2 = 8.423 ~ 1 144.176, P 均< 0.001) 人群钩虫感染均具有家庭聚 集性。钩虫感染聚集性家庭与非聚集性家庭中, 钩虫感染者每克粪便虫卵数 (egg per gram, EPG) 中位数 (四分位数间 距) 分别为180 (780) 和72 (102), 差异有统计学意义 (Z = -2.686, P < 0.05) 。钩虫感染聚集性家庭中知晓钩虫病防治知 识者所占比例低于非聚集性家庭 (24.49% vs. 51.72%; χ2 = 10.262, P < 0.05), 经常赤脚下地劳动者所占比例高于非聚集 性家庭 (30.61% vs. 13.25%; χ2 = 6.289, P < 0.05) 。结论 四川省人群钩虫感染具有家庭聚集性。钩虫病预防措施知晓 情况、是否经常赤脚下地劳动等因素与钩虫感染家庭聚集性相关。.