Seto Edmund Y W, Lee Yu J, Liang Song, Zhong Bo
School of Public Health, University of California, Berkeley, CA 94720, USA.
Trop Med Int Health. 2007 Oct;12(10):1199-209. doi: 10.1111/j.1365-3156.2007.01903.x.
To describe the exposure patterns related to schistosomiasis transmission in 10 villages in rural Xichang County, Sichuan, China.
Individual and village-level study of water contact exposure and Schistosoma japonicum reinfection; after initial infection survey and treatment, reinfection was determined 2 years later for 1604 individuals, of whom 578 also participated in a cross-sectional survey to assess their water contact behaviours.
The highest intensity of reinfection was observed in farmers aged 20-29 years, with no difference between sexes. While water contact measured as m(2)-minutes of contact was not associated with reinfection, an exposure metric computed by spatially weighting water contact by cercarial risk was correlated with both infection status and intensity. Village-level indicators based on snail density, number of infected snails, mouse bioassay data, and averaged individual-level exposures were associated with village reinfection rates.
Age-acquired immunity may be present in this population, but the study lacked sufficient power to discern differences in the exposure infection relationship with age.
描述中国四川省西昌县农村10个村庄与血吸虫病传播相关的暴露模式。
对个体和村庄层面的水接触暴露及日本血吸虫再感染情况进行研究；在初始感染调查和治疗后，2年后对1604名个体进行再感染测定，其中578人还参与了横断面调查以评估其水接触行为。
在20 - 29岁的农民中观察到最高的再感染强度，男女之间无差异。以接触面积-分钟衡量的水接触与再感染无关，但通过按尾蚴风险对水接触进行空间加权计算的暴露指标与感染状态和感染强度均相关。基于钉螺密度、感染钉螺数量、小鼠生物测定数据以及个体层面平均暴露的村庄层面指标与村庄再感染率相关。
该人群中可能存在年龄获得性免疫，但该研究缺乏足够的效能来辨别暴露感染关系随年龄的差异。
