Disease and Risk

07 Sep Disease and Risk

A significant amount of disease could be prevented through access to safe water supply, adequate sanitation services and better hygiene practices. Diarrhea disease alone amounts to an estimated 3.6 % of the total daily 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 plays a key role in preventing many more diseases, improving nutritional outcomes and for the provision of quality care in healthcare settings.

Lassa fever is another disease that thrives in an environment that lacks basic sanitation and sewage management systems. It is an acute viral hemorrhagic illness caused by Lassa virus, a member of the arenavirus family of viruses. Humans usually become infected with Lassa virus through exposure to food or household items contaminated with urine or faeces of infected Mastomys rats that live closer to waste/refuse dumps. The disease is endemic in Benin, Ghana, Guinea, Liberia, Mali, Sierra Leone, Togo and Nigeria, but probably exists in other West African countries as well. Person-to-person infections and laboratory transmission can also occur, particularly in health care settings in the absence of adequate infection prevention and control measures.  

The overall case-fatality rate is 1%. Among patients who are hospitalized with severe clinical presentation of Lassa fever, case-fatality is estimated at around 15%.

WHO quantifies the burden of diseases associated with poor WASH and sanitation, 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 – Diarrhea diseases deaths per year resulting from lack of safe drinking-water and inadequate sanitation and hygiene

58% – Proportion of the total diarrhoea deaths that could be averted through safe drinking-water, sanitation and hygiene

80% – Of people who become infected with Lassa virus have no symptoms.

1 in 5 – Infections result in severe disease, where the virus affects several organs such as the liver, spleen and kidneys.