Health Stream Article - Issue 50 - June 2008

Safer Water, Better Health

The World Health Organisation has issued a new report summarising knowledge about the disease burden caused by unsafe water and poor sanitation, the effectiveness, costs and impacts of interventions, and implications for financing. The report draws together the findings of several other WHO reports and reviews on these issues, and summarises the estimated burden of deaths and disability from water and sanitation related diseases in member countries.

Overall it is estimated that about 10% of the total burden of disease and 6.3% of all deaths worldwide could be prevented by improvements in drinking water, sanitation, hygiene and water resource management. Major contributors to the disease burden include:
• diarrhoeal diseases transmitted by contaminated drinking water, lack of sanitation and poor hygiene
• malnutrition associated with repeated diarrhoeal illness or intestinal nematode infection
• water and hygiene-related diseases including lymphatic filariasis, trachoma, schistosomiasis, malaria, dengue fever and Japanese encephalitis
• drownings, including flood-related events

Diarrhoeal illnesses were the largest single contributor, making up over 4% of the total global burden of DALYS (disability adjusted life years), or 39% of the water/sanitation/hygiene DALY burden. The consequences of malnutrition and malaria were the next most important contributors to the disease burden. The impacts of a number of water and hygiene-related diseases could not be estimated, including legionellosis, leptospirosis, conjunctivitis and otitis, physical injuries such as falls, and the adverse effects of exposure to excessive amounts of fluoride, arsenic, lead or nitrate in drinking water. The report also includes an Appendix detailing the country by country breakdown of figures for estimated deaths and DALYS lost under each of the major categories of disease.

Safer Water, Better Health, WHO,
ISBN 978 92 4 159643 5
www.who.int/quantifying_ehimpacts/publications/saferwater/en/index.html