The Global Burden of Disease study 2016 (GBD 2016) found that from 2006-2016, the number of global deaths attributable to unsafe water, sanitation, and hygiene (WASH) decreased by 25%, while lost disability-adjusted life years (DALYs) decreased by more than 35%.1 Among the top ten leading risks in 1990, rates of unsafe sanitation and unsafe water (in addition to child growth failure) have declined the most over the period of 1990–2016. However, in low socio-demographic index (SDI) countries, unsafe WASH is still the third largest contributor to the global burden of disease at 7.8% of DALYs. It is estimated that inadequate hand hygiene results in nearly 300,000 deaths annually, with the majority of deaths being among children younger than 5 years old.
In this summary, we outline key themes and findings from 117 handwashing-related research papers published in 2017. Findings are summarized in narrative form, with methodology and findings of individual studies summarized in tables.