The United Nations said yesterday that three of its agencies are backing a campaign by Afghanistan to chlorinate 17,500 shallow wells in the country's capital, Kabul, in an effort to reduce cases of illnesses including diarrhoea, which UNICEF spokesman Edward Carwardine said is responsible for an estimated 50 percent of deaths among Afghan children under 5. The United Nations said the campaign will have a significant effect against the estimated 7,800 cases of diarrhoea reported in Kabul every week. UNICEF, the World Health Organization and the World Food Program, along with non governmental organisations, helped get the chlorination campaign under way this week, Carwardine said. Chlorination takes up to three minutes. The process involves mixing chlorine powder and sand and depositing the mixture into wells to disinfect the water. In recent years, the water table in Kabul has dropped amid drought conditions, increasing reliance by communities on shallow wells, many of which pose health risks. The disinfectant teams will work over the next three months to chlorinate the wells and all 20 water reservoirs in Kabul. Up to 2.5 million people are expected to benefit. [source: UN Wire/UN News Centre]