A viewpoint in a recent edition of The Lancet discusses the importance of toilets and hand hygiene in ensuring that children grow normally in the developing world. In some regions toilets and hand hygiene are extensively lacking. Earlier studies have explored how nutrition and child growth are connected.

The viewpoint is the work of Dr Jean Humphrey, from the Johns Hopkins Bloomberg School of Public Health, Baltimore, USA. It indicates that improvement in this area could reduce the prevalence of tropical enteropathy. It is a condition in which the small intestine becomes inflamed and functions poorly due to bacterial infestation. Dr Humphrey suggests that poor toilet and hand hygiene is the source of much of this problem. The assumption is that by improving these two key factors, stunting in developing countries will significantly decrease.

A correlation with chickens is used to demonstrate Dr Humphrey’s point. Controlled studies have revealed that chicks in dirty conditions can grow normally if they are fed antibiotics. It fights away the bacteria to which they are exposed to in that environment. Chicks in the same conditions that are not given antibiotics do not develop as well. In both children and chickens, biological markers of inflammation augment substantially in insanitary conditions. This indicates that both children and chickens enter a ‘near-continuous state of growth-suppressing immune response’. In this case dietary nutrients are directed away from growth in order to provide energy and build materials for the immune response. The consequences on growth in children can be extensive. In particular, in the first two years of life when growth demands are elevated.

Dr Humphrey explains: “How can children be protected from faeces? Safe disposal of stools (ie, toilets) and handwashing with soap after faecal contact are the primary barriers to faecal-oral transmission because they prevent faeces from entering the domestic environment. Many randomised trials of handwashing have shown substantial reductions in diarrhoea, although none included the effect of these interventions on tropical enteropathy or child growth. Surprisingly, there are no published randomised trials of toilet provision on child growth or even diarrhoea.”

She writes in conclusion: “I hypothesise that prevention of tropical enteropathy, which afflicts almost all children in the developing world, will be crucial to normalise child growth, and that this will not be possible without provision of toilets. Randomised controlled trials of toilet provision and handwashing promotion that include tropical enteropathy and child growth as outcomes will give valuable evidence for this premise, and might offer a solution to the intractable problem of child undernutrition.”

“Child undernutrition, tropical enteropathy, toilets, and Handwashing”
Jean H Humphrey
Lancet 2009; 374: 1032-35
The Lancet

Written by Stephanie Brunner (B.A.)