Low-cost safe water for the world: a practical interim solution.

A very large segment of the world's population is without a microbiologically safe water supply. It is estimated that in Latin America more than 40% of the population is utilizing water of dubious quality for human consumption. This figure is probably even higher in Africa and areas of southeast Asia. Water used for drinking and food preparation can be an important route of transmission for many of the most widespread and debilitating of the diseases that afflict humans. The cholera pandemic which struck Latin America in January 1991, and has become endemic in many of the countries, continues to exemplify the public health significance of contaminated drinking water. Ideally, this neglected segment of the world's population should be served with piped water systems that provide a continuous supply of microbiologically safe water, but this would require such enormous investments of financial and human resources that it is not reasonable to expect that it will be accomplished. Interim practical measures to assure microbiologically safe water are necessary. The public health intervention to accomplish this is described in this paper and has an annual per family cost of which ranges between $1.50 and $4. It consists of providing individual households with one or preferably two suitable water containers in which to disinfect and store the essential quantities of water that need to be free of pathogens, with the containers of a design that will preclude recontamination of the contents and enable the production and distribution of the water disinfectants to be managed at the local level. It includes the necessary component of public education, promotion and involvement to establish the sustainability of the measures as a community-based endeavor. Investigation and demonstration projects are being carried out in II countries to determine and perfect and appropriate intervention, and it has been proven that it is economically, technically and socially feasible to assure microbiologically safe water for the world's population that is threatened by waterborne diseases. Carefully controlled microbiological analysis of the untreated and treated water shows that waterborne pathogens can be destroyed or inactivated, and carefully controlled epidemiological studies being carried out by the Centers for Disease Control and Prevention show that this intervention achieves considerable reduction in the incidence of water borne disease. It is recommended that all developing countries initiate programs to replicate the health measure described in this paper in order to test its validity and to adapt it to their local conditions.

Environmental health conditions and cholera vulnerability in Latin America and the Caribbean.

PIP: Epidemic cholera reached South America in January 1991 and later spread to Central America and the United States. It afflicted 312,000 people and claimed 3200 lives. Since cholera had not been in Latin America for almost 70 years, health authorities allowed environmental health barriers to cholera collapse. For example, the Governments of the Region agreed in 1961 to abide by the Charter of Punta del Este to provide water and sewerage to 70% of the urban population and 50% f the rural population by 1971. They did not achieve their goals for the rural population. In fact, at the end of 1988, water was piped to 79% of the urban households and an additional 11% of the urban population had access to a public water source. Sewerage services served 49% of the urban population and, with other methods of excreta disposal, 80% of the population had adequate excreta disposal. On the other hand, only 55% of rural inhabitants had access to either piped water or public standpipes. Further sanitary excreta disposal services only covered 32%. Besides the water quality of existing water supply systems was poor. Since feces of infected people have as many as 1 billion Vibrio cholerae and , in some of Vibrio, up to 80% of carriers exhibit only mild symptoms or no symptoms at all, it is easy to understand how cholera took hold in Latin America. Researchers identified the points of contamination responsible for the cholera outbreak in Piura and Trujillo, Peru to be wells, distribution systems, and house. Annual population growth in Latin America at 2.6% poses specific problems to providing enough water and sanitation services to all in need, especially those in marginal areas around the cities (who will make up 40% of the population by 2000).^ieng