Universally, boiling water is the most accepted way of disinfecting it but in shanty towns such as Kiberia in Kenya – where most residents live on less than US$1 per day – boiling water daily is a costly exercise. For this reason, the Savo Foundation (a local community organisation) is promoting a cheap yet effective alternative – solar disinfection (Sodis).

Using solar radiation light and temperature to destroy pathogenic bacteria that often lead to the spread of diseases, all this method requires is filling a transparent PET plastic bottle with the potentially contaminated water and leaving it outside in the sun for at least six hours.

In 84% of households that used the Sodis method, no diarrhoea had occurred, while more than two out of three households that didn’t use it reported incidences of diarrhoea.

5 July 2016
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