Water, sanitation and hygiene : interventions and diarrhoea : a systematic review and meta-analysis

The paper provides a formal systematic review and meta-analysis examining the evidence of the effectiveness of interventions intended to reduce illness through improvements in drinking water, sanitation and hygiene practices. The study showed that all interventions reduced diarrhoea morbidity, with pooled risk ratios ranging from 0.98 to 0.51, where a risk ratio of 1.0 indicates no effect and lower risk ratios indicate stronger effects. In developing countries, water quality interventions, specifically point-of-use treatment, reduced diarrhoeal illness levels. Water supply interventions reduced diarrhoea, but this effect was mainly seen with the provision of household connections and use of water without household storage. Hygiene interventions, especially those promoting hand-washing, were effective. The limited data available for sanitation interventions suggested effectiveness in reducing diarrhoea. Multifactorial interventions consisting of water supply, sanitation and hygiene education were not more effective than individual interventions. The relatively few studies that examined interventions in established market economies did support the effectiveness of hygiene, sanitation, and water supply interventions.