Transmission pathways of the food-borne carcinogen Opisthorchis viverrini

食源性致癌物 Opisthorchis viverrini 的传播途径

• 批准号: 8635905
• 负责人: ROBERT C SPEAR
• 金额: $ 20.33万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8635905
• 关键词: Adolescent; Area; Bayesian Method; Carcinogens; Cholangiocarcinoma; Clonorchis sinensis; Complex; Consumption; Data; Disease; Ecology; Ecosystem; Education; Exposure to; Fasciola hepatica; Feces; Fisheries; Fishes; Food; Food Patterns; Food Safety; Fostering; Fresh Water; Future; Genes; Genetic; Genetic Markers; Genotype; Geometry; Goals; Habitats; Harvest; Human; Incidence; Individual; Infection; Infection prevention; International; Intervention; Irrigation; Laboratories; Lead; Location; Low Income Population; Malignant Neoplasms; Maps; Measures; Methods; Microsatellite Repeats; Modification; Monitor; Morbidity - disease rate; Movement; Opisthorchis viverrini; Parasites; Parasitology; Pathway interactions; Pattern; Pharmaceutical Preparations; Play; Population; Population Genetics; Prevalence; Prevention program; Protocols documentation; Public Health; Research; Risk; Rivers; Role; Sampling; Scientist; Seasons; Site; Snails; Somatotype; Source; Southeastern Asia; Structure; Students; Surveys; System; Techniques; Testing; Thailand; Training; Tropical Disease; Water; base; contaminant transport; density; disease transmission; environmental intervention; exposed human population; foodborne; genetic epidemiology; global health; interest; multidisciplinary; neglect; population genetic structure; programs; public health relevance; reproductive; transmission process

PROJECT SUMMARY/ABSTRACT The carcinogenic liver fluke Opisthorchis viverrini is a food-borne parasite that infects approximately 10 million people, primarily in low-income populations in Southeast Asia. People become infected when they consume raw or undercooked freshwater fish harboring O. viverrini metacercariae and infection can cause cholangiocarcinoma. The proposed research will characterize transmission pathways of O. viverrini, focusing on the role of fish movement and food-distribution networks in distributing O. viverrini parasites to human populations. The research will take place in and around three connected lakes in Northeast Thailand, an area with the highest incidence of O. viverrini-induced cholangiocarcinoma in the world. Using neutral genetic markers, we will assess the population structure of the parasite in the study region in order to assess whether there exist spatially distinct foci of transmission (e.g. transmission is constrained at the scale of a lake), or if there is widespread gene flow throughout the region, suggesting parasites are readily transported between lakes and villages. We will characterize harvested fish distribution networks. Using a smartphone-based exposure assessment protocol targeting fishermen, we will quantify connections between source lakes and villages throughout the study region in order to evaluate whether these connections constitute a regional transmission network. In addition, we evaluate the potential role of fish movement in distributing parasites- O. viverrini infections in the first intermediate snail host are rare (typically, prevalence is <2%) but fish infections are common (exceeding 90% prevalence in some areas), which suggests that fish may collect parasites from a patchwork of infected snails, distributing infections across their range. We will examine the distribution of O. viverrini infections in fish, sampling fish from different sites within and between lakes in order to test the hypothesis that O. viverrini infections vary by lake, which, if detected, implies cyprinid host movements are constrained by lake geometry. We will ultimately evaluate the concordance of O. viverrini population genetic structure with the spatial patterns of food-distribution networks and fish infections, allowing us to infer key transmission pathways that act to constrain or facilitate the spread of O. viverrini. The proposed research will fill in crucial gaps in our understanding of this neglected tropical disease that can be used to guide infection prevention programs and food safety monitoring for O. viverrini and the related parasite, Clonorchis sinensis, which infects an estimated 35 million people. More generally, this disease system provides an opportunity to evaluate the role of food distribution systems and natural landscape boundaries in defining the spatial scale of infectious disease transmission.

项目摘要/摘要 致癌性肝氟腹膜viverrini是一种食物传播的寄生虫，感染了约1000万 人们，主要在东南亚的低收入人群中。人们消费时被感染 生或未煮熟的淡水鱼，藏有紫外线的甲虫和感染会导致 胆管癌。拟议的研究将表征O. viverrini的传输途径，专注于 关于鱼运动和食物分布网络在将O. viverrini寄生虫分配给人类的作用 人群。这项研究将在泰国东北部的三个相连的湖泊中进行 O. viverrini诱导的世界上胆管癌的发生率最高。使用中性遗传 标记，我们将评估研究区域中寄生虫的种群结构，以评估是否是否 存在空间上不同的传播灶（例如，在湖泊的尺度上受到限制），或者是否存在 整个地区都有广泛的基因流，表明寄生虫很容易在之间运输 湖泊和村庄。我们将表征收获的鱼类分配网络。使用基于智能手机的 针对渔民的暴露评估协议，我们将量化源湖之间的联系 整个研究区域的村庄，以评估这些联系是否构成区域 传输网络。此外，我们评估了鱼运动在分布寄生虫中的潜在作用。 第一个中间蜗牛宿主中的viverrini感染很少见（通常，患病率<2％），但鱼类感染 很常见（某些地区超过90％的患病率），这表明鱼可以从A中收集寄生虫 被感染的蜗牛的拼布，在其范围内分发感染。我们将检查O的分布。 鱼类中的维弗里尼感染，从湖泊内和湖间的不同地点采样鱼类，以测试 假设O. viverrini感染因湖泊而异，如果检测到，这意味着塞浦路斯宿主运动是 受湖几何形状的约束。我们最终将评估O. viverrini种群遗传的一致性 食物分布网络和鱼类感染的空间模式的结构，使我们能够推断钥匙 作用着限制或促进O. viverrini的传播途径。拟议的研究将 在我们对这种被忽视的热带疾病的理解中填补了关键空白，该疾病可用于引导感染 O. viverrini和相关寄生虫Clonorchis sinensis的预防计划和食品安全监测， 估计感染了3500万人。更一般地，这种疾病系统为 评估食品分配系统和自然景观边界在定义空间量表中的作用 传染病传播。