Progress in Access to Water and Sanitation between 1980 and 2010: A Driver of Decreases in Under-5 Mortality?

Global Health Metrics & Evaluation: Controversies, Innovation, Accountability, 14–16 March 2011

Leslie Mallinger, Ella Sanman, Christopher J L Murray, and Emmanuela Gakidou

“Background: An estimated 4∙2% of all deaths could be prevented simply through access to and the appropriate use of safe water, sanitation, and hygiene facilities. Many of these deaths are caused by diarrhoeal disease, the second biggest contributor to the disease burden in children under 5 years. There is a strong correlation between infant mortality and the proportion of the population without access to improved water sources. However, a complete time series for national access to improved drinking water sources and improved sanitation facilities has yet to be developed. We aimed to create estimates of the proportion of the population with access to an improved drinking water source and an improved sanitation facility, for all countries from 1980 to 2010. We also aimed to quantify the contribution of improvements in access to safe water and sanitation to the reductions in infant and child mortality.

“Methods: Data from over 1000 surveys from 169 countries were used to estimate national access to safe water and sanitation. Source and facility classifications were assigned according to the WHO-UNICEF Joint Monitoring Programme for Water Supply and Sanitation. A variant of spatial-temporal regression was used to develop estimates for country-years without survey data.

“Findings: Although progress is being achieved for both access to safe water and sanitation, access to improved water sources tends to be much higher than access to improved sanitation facilities. The rate of progress varies widely across countries. Preliminary analysis suggests that there is a significant contribution of improved access to water and sanitation to reductions in under-5 mortality across countries.

“Interpretation: Our findings can help to inform policy makers of the areas with the greatest need for interventions aiming to increase access to water and sanitation facilities, and to identify countries where successful scale-ups have occurred. Inequalities across countries in terms of infant and child mortality may be partly attributable to inequalities in access to safe water and sanitation.”