Waterborne diseases are contracted from untreated or contaminated water, usually when a person drinks or accidentally swallows the water. The illness is caused by bacteria, viruses and parasites. Human and animal feces, raw sewage, and runoffs can contaminate water. Some contaminants can be eliminated by boiling or sterilizing water.
Waterborne diseases can cause watery or bloody diarrhea that may last days or weeks.
Treatment with fluids, including oral rehydration salts solution, can prevent dehydration.