According to the WHO, there were 236,896 cholera cases in 2006, with 6,311 deaths in 52 countries - a staggering rise of 79% on the previous year.
The importance of sanitation in preventing cholera and other diarrhoeal diseases was recognised in the Millennium Development Goals, which set a target of halving the number of people without access to basic sanitation by 2015. However, this target is unlikely to be achieved because the resources allocated to it are small. Part of the reason for this neglect of sanitation is the absence of rigorous evidence for its effectiveness in prevention of disease.
However, new research by Prof Mauricio Barreto and colleagues from the Federal University of Bahia, Brazil, has shown that urban sanitation is a highly effective health measure.
More sanitation, less diarrhoea
In 1997, the city of Salvador in Brazil implemented a city-wide sanitation project. Its objective was to increase the number of households with an adequate sewer system from 26% to 80%, including extending the sewerage network, improving water supply and capacity-building in ten smaller towns in the state.
Barreto and colleagues studied the health impact of the sanitation programme in reducing cases of diarrhoea in children under the age of three years old, working with two cohorts of around 1,000 children.
The researchers found that overall prevalence of diarrhoea fell by 22%. However, in high-risk areas, where sanitary conditions were poorest, overall prevalence fell by double this amount, down 43%, despite lower than average requests by households for sewer connections.
"These results show clearly that city-wide sanitation is effective at combating diarrhoea and related diseases," says Barreto. "Importantly, they show that it has the biggest effect in the poorest areas, where sanitation – and hence, disease – is worst. Sanitation can be seen as being an equitable approach to tackling a major health problem." – (EurekAlert!)
Source: The Lancet
December 2007