Burden of disease attributable to unsafe drinking water, sanitation, and hygiene: 2019 update presents estimates of the burden of disease attributable to unsafe drinking water, sanitation and hygiene for 183 WHO Member States disaggregated by region, age and sex for the year 2019. The estimates are based on four health outcomes - diarrhoea, acute respiratory infections, undernutrition, and soil-transmitted helminthiases.
Diarrhoeal disease accounted for most of the attributable burden, with over one million deaths and 55 million DALYs. The second largest contributor was acute respiratory infections from inadequate hand hygiene, which was linked to 356 000 deaths and 17 million DALYs.
Among children under five, unsafe WASH was responsible for 395 000 deaths and 37 million DALYs, representing 7.6% of all deaths and 7.5% of all DALYs in this age group. This included 273 000 deaths from diarrhoea and 112 000 deaths from acute respiratory infections. These diseases are the top two infectious causes of death for children under five globally.
Important disparities were noted between regions and income groups. More than three-quarters of all WASH-attributable deaths occurred in the WHO African and South-East Asia regions, while 89% of attributable deaths were from low- and lower-middle income countries. However, even high-income countries are at risk, as 18% of their diarrhoeal disease burden could be prevented through improved hand hygiene practices.
While these estimates included four health outcomes for which data were available to quantify the impact, the true burden is likely to be much higher. The impacts of unsafe WASH on health are wide-ranging and go beyond disease by affecting social and mental well-being. In addition, climate change is likely to exacerbate many WASH-related diseases and risks which are not fully captured in the present estimates.
To reduce the WASH-attributable burden of disease, WHO urges governments to take the following actions with support from UN agencies, multilateral partners, the private sector and civil society organizations:
It is clear that inadequate access to safe water, sanitation, and hygiene services continues to pose a significant, and preventable, health risk, particularly to the most vulnerable populations.
The health benefits, as quantified in the report, are immense. Prioritizing those most in need is not just a moral imperative; it is key to addressing the disproportionate disease burden in low and middle-income countries and among marginalized groups in high-income countries.
A Guest Editorial