Salta city is the capital of the province with the same name located in the northwest of Argentina. Its great growth over the last decade was not organized and the population expanded to occupy places where water and sanitation were not yet available. Although the Arenales River, crossing the city, receives the impact of point and non-point source pollution, the water is used for many purposes, including domestic in the poorest areas, industrial, and recreational with children as the main users. According to the World Health Organization, an estimated 24% of the global disease burden and 23% of all deaths can be attributed to environmental factors. In particular, an estimated 94% of the diarrheal burden of disease is attributable to environment, and is associated with risk factors such as unsafe drinking water and poor sanitation and hygiene. Chronic diarrhea can be caused by an infection or other etiologies; however, most of the times the etiological agent is not identified.All the cases of diarrhea and parasitosis reported during 2005 in four public health centers of the city of Salta were classified by gender and age, analyzed, and represented geographically to show areas of higher morbidity rates, which were probably related to environmental factors.Water, poor sanitation, and pollution are candidate risk factors. Diarrhea cases showed seasonality, with the highest incidence during late spring and summer, while parasitosis was persistent throughout the year.Our spatial analysis permitted us to detect the regions of higher incidence of diarrhea and parasitosis during 2005 in the area of study.