Water, sanitation and hygiene are three intertwined determinants of the water/ill-health/poverty spectrum, considering hygiene in its broadest sense, including environmental as well as personal hygiene.

A lack of adequate sanitation is the most critical determinant of contamination of drinking water with micro-organisms.

More than 2.6 billion people – 40% of the world’s population – lack basic sanitation facilities.

Over 1 billion people around the world still use unsafe drinking water sources.

The diseases and conditions of ill-health directly associated with water, sanitation and hygiene include infectious diarrhoea (which, in turn, includes cholera, salmonellosis, shigellosis, amoebiasis and a number of other protozoal and viral infections), typhoid and paratyphoid fevers, acute hepatitis A, acute hepatitis E and F, fluorosis, arsenicosis, legionellosis, methaemoglobinaemia, schistosomiasis, trachoma, intestinal helminth infections (including ascariasis, trichuriasis and hookworm infection), dracunculiasis, scabies, dengue, filariases (including lymphatic filariasis and onchocerciasis), malaria, Japanese encephalitis, West Nile virus infection, yellow fever and impetigo.

Globally, between 1,085,000 and 2,187,000 deaths due to diarrhoeal diseases can be attributed to the ‘water, sanitation and hygiene’ risk factor, 90% of them among children under five.

Improvements in safe water supply, and in particular in hygiene and sanitation, could reduce the incidence of diarrhoea by about 20% and the number of deaths due to diarrhoea by more than 50%.

The simple act of washing hands at critical times (after using the toilet and handling infant faeces, before handling and eating food) can reduce diarrhoeal episodes by 33%.

Meeting the sanitation target means that an average of 140 million people per year need to gain access to sanitation every year until 2015. Compared to the average of 85 million per year that gained access between 1990 and 2002, this poses a huge challenge to governments and the international community alike.

The section “Did You Know…?” is taken from the 1st World Water Development Report ‘Water for People, Water for Life’, UNICEF Sanitation Statistics website and UNICEF’s Water, environment and sanitation programme website.