Water sanitation hygiene

Diseases and risks

Woman and child smiling

A significant amount of disease could be prevented through access to safe water supply, adequate sanitation services and better hygiene practices. Diarrhoeal disease alone amounts to an estimated 3.6 % of the total DALY global burden of disease and is responsible for the deaths of 1.5 million people every year (WHO 2012). It is estimated that 58% of that burden, or 842 000 deaths per year, is attributable to unsafe water supply, sanitation and hygiene and includes 361 000 deaths of children under age five, mostly in low-income countries (WHO 2014). Adequate WASH play a key role in preventing many more diseases, improving nutritional outcomes and for the provision of quality care in healthcare settings.

WHO quantifies the burden of diseases associated with poor WASH, works with scientists to obtain the most rigorous and relevant evidence on WASH and health; provide normative guidance based on a comprehensive health-risk based framework, and provide technical support on WASH in a number of areas including neglected tropical diseases, nutrition, maternal, newborn and child health, and emergencies.

Disease facts

842 000

Diarrhoeal diseases deaths per year resulting from lack of safe drinking-water and inadequate sanitation and hygiene


Proportion of the total diarrhoeal deaths that could be averted through safe drinking-water, sanitation and hygiene

Further information on diseases and risks