Child health risks attributable to swimming in contaminated water at beaches in t

描述(申请人提供)：背景：每年，人们在美国的海洋和淡水海滩上花费的时间估计为9.7亿人日。许多研究已经测量了与普通人群(所有年龄段)的粪便指示菌暴露有关的游泳相关健康风险，但个别研究通常没有招募足够的游泳者来单独评估幼儿的健康风险。儿童比成人游泳者患游泳相关疾病的风险更高，因为他们在水中呆的时间更长，更有可能吞咽水(病原体暴露的主要机制)，而且免疫系统不发达。然而，与游泳相关的风险和幼儿的健康负担代表着该领域的一个关键知识缺口：个人研究太少，无法考虑这一年龄段。2003至2009年间，我们的团队在美国的13个海洋和淡水海滩完成了纵向队列研究。我们现在有一个独特的机会来结合这些数据来填补这一知识缺口。目标：我们有两个具体的目标，我们将通过使用合并的13个海滩数据集进行二次分析来实现。AIM 1中的分析将描述儿童暴露的特征，并将使用13个海滩的水暴露和游泳者结果数据来评估肠球菌水平与10岁儿童胃肠道疾病之间的联系。目标2中的分析将估计10岁儿童的健康负担，这可归因于在肠球菌水平超过国家海滩监管指南的水中游泳。这将是第一项大规模研究，以确定在受污染的水中游泳对美国幼儿的暴露、健康风险和健康负担。方法：这项研究将结合这个提案团队进行的13项前瞻性海滩队列研究的数据，这些研究使用了高度可比性的研究设计、水样程序、实验室分析方法和健康结果测量。合并后的数据集将包括所有年龄段的74,531人(49,267名游泳运动员)和16,022名儿童(13,499名游泳运动员)？10岁。所有研究都使用定量聚合酶链式反应和基于培养的方法来测量肠球菌(粪便污染的指示菌)，以及游泳者在海滩访问后10-14天的胃肠道(GI)疾病。在目标1中，我们将确定儿童暴露的特征，并使用连续的肠球菌测量方法和二分法方法来评估10岁游泳者中肠球菌水平与随后的GI疾病之间的关联。在目标2中，我们将评估10岁儿童因在水中游泳超过国家肠球菌监管指南(&gt；35个菌落形成单位/100毫升，由EPA 1600测量)而造成的健康负担。我们将使用人口干预模型参数来估计归因风险，这比该领域以前的工作有了很大的进步。项目

DESCRIPTION (provided by applicant): Background: Each year, people spend an estimated 970 million person-days at marine and freshwater beaches in the United States. Numerous studies have measured swimming-related health risks associated with fecal indicator bacteria exposure in the general population (all ages), but individual studies usually do not enroll enough swimmers to estimate health risks separately among young children. Children are hypothesized to have a higher risk of swimming-related illness than adult swimmers because they spend more time in the water, are more likely to swallow water (the primary mechanism of pathogen exposure), and have less developed immune systems. However, swimming-associated risks and health burdens among young children represent a key knowledge gap in the field: individual studies have been too small to look at this age group. Between 2003 and 2009 our teams completed longitudinal cohort studies at 13 marine and freshwater beaches in the United States. We now have a unique opportunity to combine these data to fill this knowledge gap. Aims: We have two Specific Aims that we will achieve with secondary analyses using the combined, 13-beach dataset. The analysis in Aim 1 will characterize child exposure and will use water exposure and swimmer outcome data from the 13 beaches to estimate the association between Enterococcus levels and gastrointestinal illness among children ¿ 10 years old. The analysis in Aim 2 will estimate the health burden among children ¿ 10 years old that is attributable to swimming in water with Enterococcus levels that exceed national beach regulatory guidelines. This will be the first large-scale study to characterize exposure, health risk, and health burden from swimming in contaminated water among young children in the United States. Methods: This study will combine data from 13 prospective beach cohort studies conducted by this proposal team that used highly comparable study designs, water sampling procedures, laboratory analysis methodology, and health outcome measurement. The combined dataset will include 74,531 individuals (49,267 swimmers) of all ages and 16,022 children (13,499 swimmers) ¿ 10 years old. All studies measured Enterococcus (an indicator bacteria of fecal contamination) using both qPCR and culture-based methods, and gastrointestinal (GI) illness in swimmers 10-14 days following the beach visit. In Aim 1, we will characterize child exposure and estimate the association between Enterococcus levels and subsequent GI illness among swimmers ¿ 10 years old using continuous measures of Enterococcus and dichotomous measures which classify days by whether or not water conditions exceeded national guidelines. In Aim 2, we will estimate the health burden of GI illness among children ¿ 10 years old that is attributable to swimming in water exceeding national regulatory guidelines for Enterococcus (> 35 colony forming units / 100 ml, measured by EPA 1600). We will estimate attributable risk using a population intervention model parameter, which is a significant advance over prior work in this field. Project