Both in institutions and in communities, interventions that promote hand washing lead to significant reductions in the incidence of diarrhoea.
The WHO* estimates that diarrhoea kills around 2.2 million people annually, mostly young children in middle- or low-income countries. Encouraging children and adults to wash their hands after using the lavatory is one intervention that has potential to reduce the risk.
A team of Cochrane Researchers set out to assess the strength of evidence for the benefits of hand washing. They studied data in 14 randomised controlled trials, eight of which had been conducted in day-care centres and schools mainly in high-income countries; five had been community-based trials in low- and middle-income countries, and one looked at a specific high-risk group of HIV-infected adults living in the USA.
The data showed that interventions promoting hand washing can reduce diarrhoea episodes by 29% in day-care centres in high-income countries and by 31% in communities in low- or middle- income countries.
This is a huge benefit. For people in low-income areas this effect is comparable to providing clean water, says lead author Dr Regina Ejemot.
The challenge is to find ways of promoting hand washing, as well as to set up long term trials that test whether good practice has become part of a persons way of life, says Ejemot.