WASH interventions and child diarrhea at the interface of climate and socioeconomic position in Bangladesh

Abstract

AbstractMany diarrhea-causing pathogens are climate-sensitive, and the poorest populations are often most vulnerable to climate-related transmission. Household Water, Sanitation, and Handwashing (WASH) interventions constitute one potential effective strategy to reduce diarrhea among children, especially among low-income households. Here, capitalizing on a cluster randomized trial population (360 clusters, 8,440 measurements among children < 3 years) in rural Bangladesh, one of the world’s most climate-sensitive regions regarding precipitation regimes, we show that improved WASH substantially reduces diarrhea risk with largest benefits among poorest children and during the monsoon season. We extrapolated trial results to rural Bangladesh regions using high-resolution geospatial layers to identify areas most likely to benefit. We estimated that a similar intervention at scale could prevent 734 cases per 1,000 children per month during the seasonal monsoon, with marked heterogeneity by region. The analysis demonstrates how to extend large-scale trials to inform WASH strategies among climate-sensitive and low-income populations.