The Peru Ministry of Health reports that in 1999, there were 350 cases of diarrhea (loose, watery stools occurring more than 3 times in 24 hours) per 1000 children younger than 5 years in the district of San Juan de Lurigancho. The World Health Organization (WHO) suggests that morbidity levels associated with diarrhea can be reduced by 50% with improvements in microbiological water quality