Enteric pathogens can be transmitted within the household and the surrounding neighborhood. The objective of this study was to understand the effect of neighborhood-level sanitation coverage on contamination of the household environment with levels of fecal indicator bacteria in rural Bangladesh. We conducted spot-check observations of sanitation facilities in neighboring households (NHs) within a 20-m radius of target households with children aged 6-24 months. Sanitation facilities were defined as improved (a private pit latrine with a slab or better) or unimproved. Fecal coliforms (FCs) on children's hands and sentinel toy balls were measured and used as indicators of household-level fecal contamination. We visited 1,784 NHs surrounding 428 target households. On average, sentinel toy balls had 2.11(standard deviation [SD] = 1.37) log₁₀ colony-forming units (CFUs) of FCs/toy ball and children's hands had 2.23 (SD = 1.15) log₁₀ CFU of FCs/two hands. Access to 100% private improved sanitation coverage in the neighborhood was associated with a small and statistically insignificant difference in contamination of sentinel toy balls (difference in means = -0.13 log₁₀ CFU/toy ball; 95% confidence intervals [CI]: -0.64, 0.39; P = 0.63) and children's hands (difference in means = -0.11 log₁₀ CFU/two hands; 95% CI: -0.53, 0.32; P = 0.62). Improved sanitation coverage in the neighborhood had limited measurable effect on FCs in the target household environment. Other factors such as access to improved sanitation in the household, absence of cow dung, presence of appropriate water drainage, and optimal handwashing practice may be more important in reducing FCs in the household environment.

We conducted a cross sectional study to assess 1) the association between access to basic sanitation and fecal contamination of sentinel toy balls and 2) if other sanitation factors such as shared use and cleanliness are associated with fecal contamination of sentinel toy balls. We assessed sanitation facilities in 454 households with a child aged 6-24 months in rural Bangladesh. We defined "basic" sanitation as access to improved sanitation facilities (pit latrine with a slab or better) not shared with other households. In each household, an identical toy ball was given to the target child. After 24 hours, the balls were rinsed to enumerate fecal coliforms as an indicator of household fecal contamination. Households with basic sanitation had lower fecal coliform contamination than households with no access to basic sanitation (adjusted difference in means: -0.31 log10 colony forming units [CFU]/toy ball; 95% confidence interval [CI]: -0.61, -0.01). Shared sanitation facilities of otherwise improved type were more likely to have visible feces on the latrine slab compared with private facilities. Among households with access to improved sanitation, households with no visible feces on the latrine slab had less toy ball contamination than households with visible feces on the latrine slab (adjusted difference in means: -0.38 log10 CFU/toy ball; 95% CI: -0.77, 0.02). Access to basic sanitation may prevent fecal contamination of the household environment. An Improved sanitation facility used by an individual household may be better in preventing household fecal contamination compared with improved facilities shared with other households.

We evaluated whether provision and promotion of improved sanitation hardware (toilets and child feces management tools) reduced rotavirus and human fecal contamination of drinking water, child hands, and soil among rural Bangladeshi compounds enrolled in a cluster-randomized trial. We also measured host-associated genetic markers of ruminant and avian feces. We found evidence of widespread ruminant and avian fecal contamination in the compound environment; non-human fecal marker occurrence scaled with animal ownership. Strategies for controlling non- human fecal waste should be considered when designing interventions to reduce exposure to fecal contamination in low-income settings. Detection of a human- associated fecal marker and rotavirus was rare and unchanged by provision and promotion of improved sanitation to intervention compounds. The sanitation intervention reduced ruminant fecal contamination in drinking water and general (non-host specific) fecal contamination in soil but overall had limited effects on reducing fecal contamination in the household environment.