Treating water at home is effective in preventing diarrhoea, a major cause of death in young children in developing countries

Among infectious diseases, diarrhoea ranks as the third leading cause of both mortality and morbidity (after respiratory infections and HIV/AIDS), placing it above tuberculosis and malaria. Many of the micro-organisms that cause diarrhoea are caused by contaminated drinking water.

In high income communities, the problem is reduced by delivering clean water to homes, but this demands considerable expenditure on infrastructure that is both difficult and costly to maintain. The World Health Organization estimates that 1.1 billion people do not have access to clean water1; many more rely on water supplies that are unsafe. The UN Millennium Development Goals seek to reduce by half the portion of the population without access to safe drinking water by 2015.

The Cochrane Systematic Review, which was completed by researchers from the London School of Hygiene & Tropical Medicine, shows that interventions to improve the microbiological quality of water are effective in preventing diarrhoea. However, treating water in the home (chlorination, filtration, solar disinfection, combined flocculation/disinfection and improved storage) is considerably more effective in preventing diarrhoea than traditional interventions at the water source or point-of-distribution (wells, boreholes and communal stand posts).

“While the provision of safe piped-in water is an important long-term goal, our results demonstrate that the health gains associated with safe drinking water can be achieved by providing people with simple, affordable technologies to treat their water at home,” says lead Review Author Thomas Clasen, a Lecturer in Household Water Management at the London School of Hygiene & Tropical Medicine. “Our challenge now is to show that these interventions can be disseminated at scale on a sustainable basis”.