Determinants of Schistosomiasis Re-emergence

描述（由申请人提供）：我们对中国日本血吸虫感染传播和控制研究的广泛长期目标是开发用于设计特定地点控制方案的方法，以实现可持续的传播停止。最近在以前控制的县重新出现的传播促使我们提出这一建议，其中我们扩展了我们的目标，包括重新出现的决定因素的理解，这将通知监测方案的设计，以早期发现和最大限度地减少重新出现的规模和影响。我们的研究目标是1。测试的假设，重新出现是由两个村庄一级的因素驱动：内部潜力（一个村庄的固有能力，支持传输，包括蜗牛密度，人类和动物的主机，和农业实践）和连接（因素有关的引进寄生虫从流行地区），这可以从现有的历史记录和遥感; 2。采用病例对照研究，检验个人水平的村内和村外水接触对重新出现的村庄的初始感染具有预测作用的假设;利用一个突发性传播的随机模型来探讨偶然事件对有效监测系统设计的影响。与公共卫生的相关性：这项研究与公共卫生有关，因为它将增加我们对与传染病重新出现有关的因素的了解。通过这种理解，可以制定更好的监测方法来保护公众健康。

DESCRIPTION (provided by applicant): The broad long-term objectives of our research on the transmission and control of Schistosoma japonicum infections in China have been to develop methods for the design of site-specific control programs to achieve the sustainable cessation of transmission. The recent re-emergence of transmission in formerly controlled counties has prompted this proposal, in which we extend our objectives to include an understanding of the determinants of re-emergence, which will inform the design of surveillance programs for the early detection and minimization of the scale and impact of re-emergence. The aims of our research are to 1. Test the hypothesis that re-emergence is driven by two village-level factors: internal potential (a village's inherent ability to support transmission that includes snail density, human and animal hosts, and agricultural practices) and connectivity (factors related to the introduction of parasites from endemic areas), which can be obtained from existing historical records and remote sensing; 2. Using a case-control study, test the hypothesis that individual-level within-village and outside-village water contact is predictive of the initial infections in re-emergent villages; and 3. Utilize a stochastic model of re-emergent transmission to explore the effect of chance events on the design of an effective surveillance system. Relevance to public health: This research is relevant to public health, in that it will increase our knowledge of the factors related to infectious disease re-emergence. Through this understanding, better surveillance approaches can be developed to protect public health.