The purpose of this study is to determine the health impact of a basic sanitation intervention in Maputo, Mozambique.

We have designed a controlled, before-and-after (CBA) effectiveness study to estimate the health impacts of an urban sanitation intervention in informal neighborhoods of Maputo, Mozambique, including an assessment of whether exposures and health outcomes vary by localized population density. The intervention consists of private pour-flush latrines (to septic tank) shared by multiple households in compounds or household clusters. We will measure objective health outcomes in approximately 1000 children (500 children with household access to interventions, 500 controls using existing shared private latrines in poor sanitary conditions), at two time points: immediately before the intervention and at follow-up after 12 months. The primary outcome is combined prevalence of enteric infections among children under 5 years of age. Secondary outcome measures include soil transmitted helminth (STH) re-infection in children following baseline de-worming and prevalence of reported gastrointestinal illness. We will use exposure assessment, fecal source tracking, and microbial transmission modeling to examine whether and how routes of exposure for diarrheagenic pathogens and STHs vary and transmission impacts of the pathogens following introduction of effective sanitation. Our analysis will focus specifically on the impact of localized population density as a potential modifier of sanitation-related exposures.

Inclusion Criteria:

• Children normally resident in households with access to new shared sanitation (the intervention) as selected by implementing organisation (WSUP) or control children normally resident in households sharing existing shared sanitation within geographically delimited project bounds and meeting WSUP site selection criteria (including number of people served)

Exclusion Criteria:

• Refusal to participate