In 1992, the US Centers for Disease Control and Prevention (CDC) and the Pan American Health Organization collaborated to reduce waterborne diseases in developing countries. They called the new methodology the Safe Water System (SWS); it consisted of three components:[3]
- Water treatment at point of use with a locally made diluted bleach solution
- Preventing recontamination of water by safely storing treated water in containers with narrow mouths, lids, and spigots
- Education to improve the handling and sanitation of food and water
From 1994 to 1995, the CDC implemented the SWS in Bolivia in a pilot experiment, where it improved water quality and reduced diarrheal illness by 40%.[4] Following the success of the program in Bolivia, the CDC received permission from the Zambian Ministry of Health to conduct field trials in 1998 in Kitwe, Zambia. Compared to the control group, the households that received the SWS and education on best hygiene practices experienced a 48% reduced risk of diarrheal disease.[3] In response to marketing efforts by the CDC, the sanitizing solution, sold as Clorin, experienced a steep increase in demand in Zambia. In 1999, about 187,000 bottles of Clorin were sold; in 2004, over 1.8 million bottles were sold. Each bottle sanitizes enough water for one month for a family of six. Clorin is subsidized by the United States Agency for International Development (USAID); as of 2003, each bottle is sold for US$0.09, with USAID paying $0.33 per bottle (each bottle therefore has a net cost of $0.24 to USAID).[5]
Household water treatment now encompasses other methods, such as use of flocculants that cause contaminants within water to sink to the bottom of a container or float at the top where they can be more easily removed. Methods like disinfectant powder, solar water disinfection, ceramic filtration, and slow sand filtration are also incorporated.[6]
