U.S. Environmental Protection Agency, Office of Research and Development, Research Triangle Park, North Carolina, United States of America.
F.I. Proctor Foundation, University of California, San Francisco, San Francisco, California, United States of America.
PLoS One. 2022 Apr 12;17(4):e0266749. doi: 10.1371/journal.pone.0266749. eCollection 2022.
Children may be at higher risk for swimming-associated illness following exposure to fecally-contaminated recreational waters. We analyzed a pooled data set of over 80,000 beachgoers from 13 beach sites across the United States to compare risks associated with the fecal indicator bacteria Enterococcus spp. (measured by colony forming units, CFU and quantitative polymerase chain reaction cell equivalents, qPCR CE) for different age groups across different exposures, sites and health endpoints.
Sites were categorized according to the predominant type of fecal contamination (human or non-human). Swimming exposures of varying intensity were considered according to degree of contact and time spent in the water. Health endpoints included gastrointestinal and respiratory symptoms and skin rashes. Logistic regression models were used to analyze the risk of illness as a function of fecal contamination in water as measured by Enterococcus spp. among the exposed groups. Non-swimmers (those who did not enter the water) were excluded from the models to reduce bias and facilitate comparison across groups.
Gastrointestinal symptoms were the most sensitive health endpoint and strongest associations were observed with Enterococcus qPCR CE at sites impacted by human fecal contamination. Under several exposure scenarios, associations between illness and Enterococcus spp. levels were significantly higher among children compared to adolescents and adults. Respiratory symptoms were also associated with Enterococcus spp. exposures among young children at sites affected by human fecal sources, although small sample sizes resulted in imprecise estimates for these associations.
Under many exposure scenarios, children were at higher risk of illness associated with exposure to fecal contamination as measured by the indicator bacteria Enterococcus spp. The source of fecal contamination and the intensity of swimming exposure were also important factors affecting the association between Enterococcus spp. and swimming-associated illness.
儿童在接触受粪便污染的娱乐性水域后，可能面临更高的游泳相关疾病风险。我们分析了来自美国 13 个海滩的超过 80000 名海滩游客的汇总数据集，以比较不同年龄段、不同暴露程度、不同地点和不同健康终点与粪便指示菌肠球菌属（通过菌落形成单位（CFU）和定量聚合酶链反应细胞当量（qPCR CE）测量）相关的风险。
根据粪便污染的主要类型（人类或非人类）对地点进行分类。根据接触程度和在水中停留的时间，考虑了不同强度的游泳暴露。健康终点包括胃肠道和呼吸道症状以及皮疹。使用逻辑回归模型分析了暴露组中肠球菌属作为水中粪便污染指标的情况下，疾病风险与粪便污染之间的关系。非游泳者（未入水者）被排除在模型之外，以减少偏差并促进组间比较。
胃肠道症状是最敏感的健康终点，在受人类粪便污染影响的地点，与肠球菌 qPCR CE 的关联最为密切。在几种暴露情况下，与肠球菌 spp 相比，儿童的疾病与肠球菌 spp 水平之间的关联明显更高。在受人类粪便源影响的地点，幼儿的呼吸道症状也与肠球菌 spp 暴露有关，尽管这些关联的估计值因样本量小而不够精确。
在许多暴露情况下，与指示菌肠球菌属测量的粪便污染暴露相关的疾病风险，儿童比青少年和成年人更高。粪便污染的来源和游泳暴露的强度也是影响肠球菌 spp 与游泳相关疾病之间关联的重要因素。
