Am J Epidemiol. 2021 Jul 1;190(7):1243-1252. doi: 10.1093/aje/kwaa292.
Urbanization increases human mobility in ways that can alter the transmission of classically rural, vector-borne diseases like schistosomiasis. The impact of human mobility on individual-level Schistosoma risk is poorly characterized. Travel outside endemic areas may protect against infection by reducing exposure opportunities, whereas travel to other endemic regions may increase risk. Using detailed monthly travel- and water-contact surveys from 27 rural communities in Sichuan, China, in 2008, we aimed to describe human mobility and to identify mobility-related predictors of S. japonicum infection. Candidate predictors included timing, frequency, distance, duration, and purpose of recent travel as well as water-contact measures. Random forests machine learning was used to detect key predictors of individual infection status. Logistic regression was used to assess the strength and direction of associations. Key mobility-related predictors include frequent travel and travel during July-both associated with decreased probability of infection and less time engaged in risky water-contact behavior, suggesting travel may remove opportunities for schistosome exposure. The importance of July travel and July water contact suggests a high-risk window for cercarial exposure. The frequency and timing of human movement out of endemic areas should be considered when assessing potential drivers of rural infectious diseases.
城市化以改变血吸虫病等经典农村媒介传播疾病传播的方式增加了人类的流动性。人类流动对个体层面血吸虫病风险的影响尚未得到充分描述。在流行地区以外的旅行可能会通过减少接触机会来预防感染，而前往其他流行地区则可能会增加风险。我们使用了 2008 年中国四川省 27 个农村社区详细的每月旅行和水接触调查，旨在描述人类流动性，并确定与流动性相关的血吸虫病感染预测因素。候选预测因素包括最近旅行的时间、频率、距离、持续时间和目的，以及水接触措施。随机森林机器学习用于检测个体感染状态的关键预测因素。逻辑回归用于评估关联的强度和方向。关键的流动性相关预测因素包括频繁旅行和 7 月旅行——均与降低感染概率和减少从事危险水接触行为的时间有关，这表明旅行可能会消除血吸虫暴露的机会。7 月旅行和 7 月水接触的重要性表明了尾蚴暴露的高风险窗口。在评估农村传染病的潜在驱动因素时，应考虑出流行地区的人类流动的频率和时间。
