BackgroundEnteric infections are common where public health infrastructure is lacking. This study assesses risk factors for a range of enteric infections among children living in low-income, unplanned communities of urban Maputo, Mozambique.Methods & findingsWe conducted a cross-sectional survey in 17 neighborhoods of Maputo to assess the prevalence of reported diarrheal illness and laboratory-confirmed enteric infections in children. We collected stool from children aged 1–48 months, independent of reported symptoms, for molecular detection of 15 common enteric pathogens by multiplex RT-PCR. We also collected survey and observational data related to water, sanitation, and hygiene (WASH) characteristics; other environmental factors; and social, economic, and demographic covariates.We analyzed stool from 759 children living in 425 household clusters (compounds) representing a range of environmental conditions. We detected ≥1 enteric pathogens in stool from most children (86%, 95% confidence interval (CI): 84–89%) though diarrheal symptoms were only reported for 16% (95% CI: 13–19%) of children with enteric infections and 13% (95% CI: 11–15%) of all children. Prevalence of any enteric infection was positively associated with age and ranged from 71% (95% CI: 64–77%) in children 1–11 months to 96% (95% CI: 93–98%) in children 24–48 months. We found poor sanitary conditions, such as presence of feces or soiled diapers around the compound, to be associated with higher risk of protozoan infections. Certain latrine features, including drop-hole covers and latrine walls, and presence of a water tap on the compound grounds were associated with a lower risk of bacterial and protozoan infections. Any breastfeeding was also associated with reduced risk of infection.ConclusionsWe found a high prevalence of enteric infections, primarily among children without diarrhea, and weak associations between bacterial and protozoan infections and environmental risk factors including WASH. Findings suggest that environmental health interventions to limit infections would need to be transformative given the high prevalence of enteric pathogen shedding and poor sanitary conditions observed.Trial registrationClinicalTrials.gov NCT02362932

We conducted a controlled before-and-after trial to evaluate the impact of an onsite urban sanitation intervention on the prevalence of enteric infection, soil transmitted helminth re-infection, and diarrhea among children in Maputo, Mozambique. A non-governmental organization replaced existing poor-quality latrines with pour-flush toilets with septic tanks serving household clusters. We enrolled children aged 1-48 months at baseline and measured outcomes before and 12 and 24 months after the intervention, with concurrent measurement among children in a comparable control arm. Despite nearly exclusive use, we found no evidence that intervention affected the prevalence of any measured outcome after 12 or 24 months of exposure. Among children born into study sites after intervention, we observed a reduced prevalence of Trichuris and Shigella infection relative to the same age group at baseline (<2 years old). Protection from birth may be important to reduce exposure to and infection with enteric pathogens in this setting.

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Background. Onsite sanitation serves more than 740 million people in urban areas, primarily in low-income countries. Although this critical infrastructure may play an important role in controlling enteric infections in high-burden settings, its health impacts have never been evaluated in a controlled trial. Methods. We conducted a controlled before and after trial to evaluate the impact an onsite urban sanitation intervention on the prevalence of bacterial and protozoan infection (primary outcome), soil transmitted helminth (STH) re-infection, and seven-day period prevalence of diarrhoea among children living in informal neighborhoods of Maputo, Mozambique. A non-governmental organization replaced existing shared latrines in poor condition with engineered pour-flush toilets with septic tanks serving household clusters. We enrolled children aged 1-48 months at baseline and measured outcomes before the intervention and at 12 and 24 months following intervention. We measured outcomes concurrently among children served by the sanitation improvements and those in a comparable control arm served by existing poor sanitation. The trial was registered at ClinicalTrials.gov, number NCT02362932. Findings. At baseline, we enrolled 454 children from 208 intervention clusters and 533 children from 287 control clusters. We enrolled or re-visited 462 intervention and 477 control children 12 months 60 after intervention and 502 intervention and 499 control children 24 months after intervention. Despite nearly exclusive use of the intervention, we found no evidence that engineered onsite sanitation affected the overall prevalence of any measured bacterial or protozoan infection (12-month adjusted prevalence ratio 1.05, 95% CI [0.95-1.16]; 24-month adjusted prevalence ratio 0.99, 95% CI [0.91-1.09]), any STH re-infection (1.11 [0.89-1.38]; 0.95 [0.77-1.17]), or diarrhoea (1.69 [0.89-3.21]; 0.84 [0.47-1.51]) after 12 or 24 months of exposure. Among children born into study sites after the intervention and measured at the 24-month visit, we observed a reduced prevalence of any STH re-infection of 49% (adjusted prevalence ratio 0.51 [95% confidence interval 0.27 - 0.95]), Trichuris of 76% (0.24 [0.10 - 0.60]), and Shigella infection by 51% (0.49 [0.28-0.85]) relative to the same age group at baseline. Interpretation. The intervention did not reduce the overall prevalence of enteric infection and diarrhoea among all enrolled children but may have substantially reduced the prevalence of STHs and Shigella among children born into clusters with sanitary improvements.

Sanitary surveys are used in low- and middle-income countries to assess water, sanitation, and hygiene conditions, but have rarely been compared with direct measures of environmental fecal contamination. We conducted a cross-sectional assessment of sanitary conditions and E. coli counts in soils and on surfaces of compounds (household clusters) in low-income neighborhoods of Maputo, Mozambique. We adapted the World Bank’s Urban Sanitation Status Index to implement a sanitary survey tool specifically for compounds: a Localized Sanitation Status Index (LSSI) ranging from zero (poor sanitary conditions) to one (better sanitary conditions) calculated from 20 variables that characterized local sanitary conditions. We measured the variation in the LSSI with E. coli counts in soil (nine locations/compound) and surface swabs (seven locations/compound) in 80 compounds to assess reliability. Multivariable regression indicated that a ten-percentage point increase in LSSI was associated with 0.05 (95% CI: 0.00, 0.11) log10 fewer E. coli/dry gram in courtyard soil. Overall, the LSSI may be associated with fecal contamination in compound soil; however, the differences detected may not be meaningful in terms of public health hazards.

Preventing infectious disease has often been the primary rationale for public investment in sanitation. However, broader aspects of sanitation such as privacy and safety are important to users across settings, and have been linked to mental wellbeing. The aim of this study is to investigate what people most value about sanitation in low-income areas of Maputo, Mozambique, to inform a definition and conceptual model of sanitation-related quality of life. Our approach to qualitative research was rooted in economics and applied the capability approach, bringing a focus on what people had reason to value. We undertook 19 in-depth interviews and 8 focus group discussions. After eliciting attributes of “a good life” in general, we used them to structure discussion of what was valuable about sanitation. We applied framework analysis to identify core attributes of sanitation-related quality of life, and used pile-sorting and triad exercises to triangulate findings on attributes’ relative importance. The five core attributes identified were health, disgust, shame, safety, and privacy. We present a conceptual model illustrating how sanitation interventions might improve quality of life via changes in these attributes, and how changes are likely to be moderated by conversion factors (e.g. individual and environmental characteristics). The five capability-based attributes are consistent with those identified in studies of sanitation-related insecurity, stress and motives in both rural and urban areas, which is supportive of theoretical generalisability. Since two people might experience the same toilet or level of sanitation service differently, quality of life effects of interventions may be heterogeneous. Future evaluations of sanitation interventions should consider how changes in quality of life might be captured.

Fecal source tracking (FST) may be useful to assess pathways of fecal contamination in domestic environments and to estimate the impacts of water, sanitation, and hygiene (WASH) interventions in low-income settings. We measured two nonspecific and two human-associated fecal indicators in water, soil, and surfaces before and after a shared latrine intervention from low-income households in Maputo, Mozambique, participating in the Maputo Sanitation (MapSan) trial. Up to a quarter of households were impacted by human fecal contamination, but trends were unaffected by improvements to shared sanitation facilities. The intervention reduced Escherichia coli gene concentrations in soil but did not impact culturable E. coli or the prevalence of human FST markers in a difference-in-differences analysis. Using a novel Bayesian hierarchical modeling approach to account for human marker diagnostic sensitivity and specificity, we revealed a high amount of uncertainty associated with human FST measurements and intervention effect estimates. The field of microbial source tracking would benefit from adding measures of diagnostic accuracy to better interpret findings, particularly when FST analyses convey insufficient information for robust inference. With improved measures, FST could help identify dominant pathways of human and animal fecal contamination in communities and guide the implementation of effective interventions to safeguard health.

Two billion people globally lack access to a basic toilet. While improving sanitation reduces infectious disease, toilet users often identify privacy, safety and dignity as more important. However, these outcomes have not been incorporated in sanitation-related economic evaluations. This illustrates the general challenge of outcome measurement and valuation in the economic evaluation of public health interventions, and risks misallocating the US$ 20 billion invested in sanitation in low-and middle-income countries every year. In this study in urban Mozambique, we develop an instrument to measure sanitation-related quality of life (SanQoL). Applying methods from health economics and the capability approach, we develop a descriptive system to measure five attributes identified in prior qualitative research: disgust, health, shame, safety and privacy.Sampling individuals from the intervention and control groups of a sanitation intervention trial, we elicit attribute ranks to value a SanQoL index and assess its validity and reliability. In combination with a measure of time using a sanitation service, SanQoL can quantify incremental benefits in a sanitation-focused cost-effectiveness analysis. After monetary valuation based on willingness to pay, QoL benefits could be summed with health gains in cost-benefit analysis, the most common method in sanitation economic evaluations.