Association of Supply Type with Fecal Contamination of Source Water and Household Stored Drinking Water in Developing Countries: A Bivariate Meta-analysis. Env Health Perspec, May 2015.
Authors: Katherine F. Shields, Robert E.S. Bain, Ryan Cronk, Jim A. Wright, and Jamie Bartram
Background: Access to safe drinking water is essential for health. Monitoring access to drinking water focuses on water supply type at the source, but there is limited evidence on whether quality differences at the source persist in water stored in the household.
Objectives: To assess the extent of fecal contamination at the source and in household storedwater (HSW) and explore the relationship between contamination at each of these sampling points and water supply type.
Methods: A bivariate random-effects meta-analysis of 45 studies, identified through asystematic review, that reported either the proportion of samples free of fecal indicator bacteria and/or individual sample bacteria counts for source and HSW, disaggregated by supply type.
Results: Water quality deteriorated substantially between source and stored water. Mean percentage of contaminated samples (noncompliance) at the source was 46% (95% CI: 33, 60%) while mean noncompliance in HSW was 75% (95% CI: 64, 84%). Water supply type was significantly associated with noncompliance at the source (p < .001) and in HSW (p = 0.03). Source water (OR = 0.2; 95% CI: 0.1, 0.5) and HSW (OR = 0.3; 95% CI: 0.2, 0.8) from pipedsupplies had significantly lower odds of contamination when compared to non-piped water,potentially due to residual chlorine.
Conclusions: Piped water is less likely to be contaminated compared to other water supply typesat both the source and in HSW. A focus on upgrading water services to piped supplies may helpimprove safety, including for those drinking stored water.
