Effectiveness of infrastructural interventions to improve access to safe drinking water in Latin America and the Caribbean on the burden of diarrhoea in children <5 years: a systematic literature review and narrative synthesis.

Globally, Latin America and the Caribbean (LAC) has one of the lowest rates of equitable access to safely managed drinking water. This systematic literature review assessed the effectiveness of infrastructure interventions to provide equitable access to safely managed drinking water in LAC on the burden of diarrhoea in children <5 years. The review was conducted in February 2024 using Ovid MEDLINE, Embase, Global Health, and the Cochrane Library with inclusion criteria: quantitative study designs of intervention effectiveness on burden of diarrhoea in children; conducted in LAC; studies published since 1 January 2000; and full-text available in English. Study quality was assessed via the US Agency for Healthcare Research and Quality scale. Reported quantitative data for diarrhoea burden of disease were extracted, and thematic analysis informed a narrative synthesis. Six studies from three countries in LAC with >110,000 data-points were included. Water supply infrastructure interventions were effective at reducing the burden of diarrhoea in children <5 years. Household level, rather than community level, access to a piped water supply, a continuous reliable service with <1 day of service interruption per month, and cash transfer programs for environmental public health programs, were identified as key contributors to water infrastructure intervention effectiveness. Previous water supply infrastructure interventions which include the provision of a safe drinking water supply are effective in reducing burden of diarrhoea in children. Future studies are needed to develop a comprehensive understanding of the unique features which contribute to water infrastructure effectiveness.