Water and health: Global and national aspects.

Although water is recognized as essential for the appropriate functioning of biological systems and human health, many countries and a large part of the global population are water stressed. The expected changes to the hydrologic cycle brought about by the process of global climate change will aggravate this situation. Almost 90 % of the four billion diarrhea episodes occurring globally each year are linked to deficiencies in sewage disposal and the supply of safe water. In Brazil, the most important public health problems associated to water are: diarrheal diseases, schistosomiasis and other helminth infections, leptospirosis, vector-borne diseases (e.g. malaria and dengue fever) and poisoning by Cyanobacteria toxins. It is suggested, for Brazil, the setting of quantitative goals for reduction in childhood diarrhea in the next 5 years as well as development of integrated indicators for the monitoring of water-and-sanitation-related health problems.