Identifying the origin of fecal contamination can support more effective interventions to interrupt enteric pathogen transmission. Microbial source tracking (MST) assays may help to identify environmental routes of pathogen transmission although these assays have performed poorly in highly contaminated domestic settings, highlighting the importance of both diagnostic validation and understanding the context-specific ecological, physical, and sociodemographic factors driving the spread of fecal contamination. We assessed fecal contamination of compounds (clusters of 2–10 households that share sanitation facilities) in low-income neighborhoods of urban Maputo, Mozambique, using a set of MST assays that were validated with animal stool and latrine sludge from study compounds. We sampled five environmental compartments involved in fecal microbe transmission and exposure: compound water source, household stored water and food preparation surfaces, and soil from the entrance to the compound latrine and the entrances to each household. Each sample was analyzed by culture for the general fecal indicator Escherichia coli (cEC) and by real-time PCR for the E. coli molecular marker EC23S857, human-associated markers HF183/BacR287 and Mnif, and GFD, an avian-associated marker. We collected 366 samples from 94 households in 58 compounds. At least one microbial target (indicator organism or marker gene) was detected in 96% of samples (353/366), with both E. coli targets present in the majority of samples (78%). Human targets were frequently detected in soils (59%) and occasionally in stored water (17%) but seldom in source water or on food surfaces. The avian target GFD was rarely detected in any sample type but was most common in soils (4%). To identify risk factors of fecal contamination, we estimated associations with sociodemographic, meteorological, and physical sample characteristics for each microbial target and sample type combination using Bayesian censored regression for target concentration responses and Bayesian logistic regression for target detection status. Associations with risk factors were generally weak and often differed in direction between different targets and sample types, though relationships were somewhat more consistent for physical sample characteristics. Wet soils were associated with elevated concentrations of cEC and EC23S857 and odds of detecting HF183. Water storage container characteristics that expose the contents to potential contact with hands and other objects were weakly associated with human target detection. Our results describe a setting impacted by pervasive domestic fecal contamination, including from human sources, that was largely disconnected from the observed variation in socioeconomic and sanitary conditions. This pattern suggests that in such highly contaminated settings, transformational changes to the community environment may be required before meaningful impacts on fecal contamination can be realized.

识别粪便污染的起源可以支持更有效的干预措施来中断肠道病原体的传播。微生物源跟踪（MST）分析可能有助于确定病原体传播的环境途径，尽管这些分析在高度污染的家庭环境中表现不佳，突显了诊断验证和理解环境特定的生态，物理和社会人口统计学因素的重要性。粪便污染的蔓延。我们使用一组经过MST分析验证的粪便污染物（莫桑比克马普托市区低收入社区的粪便污染人群（2-10个共享卫生设施的居民群）），这些方法已通过研究粪便的动物粪便和厕所污泥进行了验证。我们采样了五个与粪便微生物传播和暴露有关的环境区室：复合水源，家庭存储的水和食物制备表面以及从复合厕所入口到每个家庭入口的土壤。通过培养分析每个样品的一般粪便指标大肠杆菌（cEC），并通过实时PCR检测大肠杆菌分子标记EC23S857，人类相关标记HF183 / BacR287和Mnif，以及GFD（禽类相关标记）。我们从94个家庭的58个化合物中收集了366个样本。在样品（366分之353）的96％中检测到的至少一种微生物目标（指示生物或标记基因），与两个大肠杆菌大多数样品（78％）中存在目标。经常在土壤（59％）中发现人类目标，偶尔在储水（17％）中发现人类目标，但很少在原水或食物表面发现。在任何样品类型中均很少检测到禽目标GFD，但在土壤中最为常见（4％）。为了确定粪便污染的风险因素，我们使用贝叶斯删失回归作为目标浓度响应，并使用贝叶斯逻辑回归在目标检测状态下估计每种微生物目标和样本类型组合的社会人口统计学，气象和物理样本特征之间的关系。与风险因素的关联通常较弱，并且在不同目标和样本类型之间的方向通常会有所不同，尽管对于物理样本特征而言，这种关系更为一致。潮湿的土壤与cEC和EC23S857的浓度升高以及检测HF183的可能性有关。使内容物容易与手和其他物体接触的储水容器特性与人类目标检测之间的关联微弱。我们的结果描述了一种环境，该环境受到普遍的家庭粪便污染（包括来自人类的污染）的影响，这与观察到的社会经济和卫生条件的变化大体上无关。这种模式表明，在这种高度污染的环境中，在实现对粪便污染的有意义影响之前，可能需要对社区环境进行改造。将内容物暴露于可能与手和其他物体接触的储水容器特性与人类目标检测之间的联系较弱。我们的结果描述了一种环境，该环境受到普遍的家庭粪便污染（包括来自人类的污染）的影响，这与观察到的社会经济和卫生条件的变化大体上无关。这种模式表明，在这种高度污染的环境中，在实现对粪便污染的有意义影响之前，可能需要对社区环境进行改造。将内容物暴露于可能与手和其他物体接触的储水容器特性与人类目标检测之间的联系较弱。我们的结果描述了一种环境，该环境受到普遍的家庭粪便污染（包括来自人类的污染）的影响，这与观察到的社会经济和卫生条件的变化大体上无关。这种模式表明，在这种高度污染的环境中，在实现对粪便污染的有意义影响之前，可能需要对社区环境进行改造。这在很大程度上与观察到的社会经济和卫生条件的变化无关。这种模式表明，在这种高度污染的环境中，在实现对粪便污染的有意义影响之前，可能需要对社区环境进行改造。这在很大程度上与观察到的社会经济和卫生条件的变化无关。这种模式表明，在这种高度污染的环境中，在实现对粪便污染的有意义影响之前，可能需要对社区环境进行改造。