Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States of America.
Center for Global Safe Water, Sanitation, and Hygiene, Emory University, Atlanta, GA, United States of America.
PLoS One. 2018 Jul 3;13(7):e0199304. doi: 10.1371/journal.pone.0199304. eCollection 2018.
Exposure to fecal contamination in public areas, especially in dense, urban environments, may significantly contribute to enteric infection risk. This study examined associations between sanitation and fecal contamination in public environments in four low-income neighborhoods in Accra, Ghana. Soil (n = 72) and open drain (n = 90) samples were tested for E. coli, adenovirus, and norovirus. Sanitation facilities in surveyed households (n = 793) were categorized by onsite fecal sludge containment ("contained" vs. "uncontained") using previous Joint Monitoring Program infrastructure guidelines. Most sanitation facilities were shared by multiple households. Associations between spatial clustering of household sanitation coverage and fecal contamination were examined, controlling for neighborhood and population density (measured as enumeration areas in the 2010 census and spatially matched to sample locations). E. coli concentrations in drains within 50m of clusters of contained household sanitation were more than 3 log-units lower than those outside of clusters. Further, although results were not always statistically significant, E. coli concentrations in drains showed consistent trends with household sanitation coverage clusters: concentrations were lower in or near clusters of high coverage of household sanitation facilities-especially contained facilities-and vice versa. Virus detection in drains and E. coli concentrations in soil were not significantly associated with clustering of any type of household sanitation and did not exhibit consistent trends. Population density alone was not significantly associated with any of the fecal contamination outcomes by itself and was a significant, yet inconsistent, effect modifier of the association between sanitation clusters and E. coli concentrations. These findings suggest clustering of contained household sanitation, even when shared, may be associated with lower levels of fecal contamination within drains in the immediate public domain. Further research is needed to better quantify these relationships and examine impacts on health.
公共区域，尤其是在密集的城市环境中，粪便污染暴露可能会显著增加肠道感染的风险。本研究在加纳阿克拉的四个低收入社区调查了公共环境中的卫生和粪便污染之间的关联。土壤（n = 72）和露天排水沟（n = 90）样本中检测到大肠杆菌、腺病毒和诺如病毒。使用之前的联合监测计划基础设施指南，对调查家庭中的卫生设施（n = 793）进行了现场粪便污泥封存分类（“封存”与“未封存”）。大多数卫生设施由多个家庭共享。在控制社区和人口密度（以 2010 年人口普查中的计数区来衡量，并与样本位置空间匹配）的情况下，检验了家庭卫生覆盖范围空间聚类与粪便污染之间的关联。距离包含家庭卫生设施集群 50 米以内的排水沟中的大肠杆菌浓度比集群外的浓度低 3 个对数单位以上。此外，尽管结果并不总是具有统计学意义，但在排水沟中的大肠杆菌浓度与家庭卫生覆盖范围聚类之间存在一致的趋势：在家庭卫生设施高覆盖范围的集群中或附近，浓度较低，反之亦然。在排水沟中检测到的病毒和土壤中的大肠杆菌浓度与任何类型的家庭卫生聚类均无显著关联，也没有表现出一致的趋势。单独的人口密度本身与任何粪便污染结果均无显著关联，并且是卫生聚类与大肠杆菌浓度之间关联的显著但不一致的效应修饰剂。这些发现表明，即使是共享的封存家庭卫生设施的聚类，也可能与公共领域内排水沟中较低水平的粪便污染有关。需要进一步研究以更好地量化这些关系并研究对健康的影响。
