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Waterborne Diseases & IllnessesWaterborne Diseases & Illnesses

The Basics

Would you want to go swimming in a pool of bugs, worms, and chemicals? In some natural water sources, you actually would be! You just wouldn’t be able to see them. Tiny organisms like bacteria, viruses, and parasites may live in our water supplies. Chemicals and heavy metals can get into our water, too. If you drink that water, wash your food with it, or swim or bathe in it, it might make you sick.

We call these illnesses waterborne diseases because people get them from contaminated (unsafe) water. The water can also be harmful to animals. It may cause minor or serious illness, or even death. Contaminated water can lead to disease outbreaks in a local area, country, or across the world.


Did you know ?

The largest waterborne disease outbreak in United States history happened in Milwaukee, Wisconsin in 1993. Over 400,000 people got sick when a parasite was found in the city's drinking water supply.

Learn More

Explore the links below to learn more about how human activity can increase the risks of disease outbreaks, and what you can do to protect yourself.

Read About It Read About It

Algae Blooms (Tox Town - National Library of Medicine) - Describes the hazardous environmental effects of algae blooms.

High Tides, Red Tides, and Not-so-White Water (Washington State Department of Health) - Describes problems such as flooding, diseases, and too much salt that result from high tides, red tides, and not-so-white water.

Nova: The Most Dangerous Woman in America - Typhoid Mary (Public Broadcasting Services) - Resource links to information on Typhoid Mary, including books, teacher's guide, and videos.

Typhoid Fever (Medline Plus - National Library of Medicine) - Information about typhoid fever: causes, symptoms, tests, and treatment options.

Water-related Diseases and Contaminants in Public Water Systems (Centers for Disease Control and Prevention) - Information and links to top 10 waterborne illnesses and outbreaks in public water systems.

Cholera (Medline Plus - National Library of Medicine) - Overview of the causes, symptoms, and treatment of cholera.

Cholera (Centers for Disease Control and Prevention) - Information on cholera risk factors, prevention, diagnosis and treatment.

Cholera: Old Disease, New Dangers (Johns Hopkins University Ecohealth) - Information about cholera, how it can spark an epidemic, and its link to climate change.

Parasites - Cryptosporidium (Centers for Disease Control and Prevention) - Information about cryptosporidum, a microscopic parasite that causes the disease cryptosporidiosis, and its treatment, diagnosis, and prevention.

How Diseases Get Spread (Johns Hopkins University Ecohealth) - Explains how environmental changes can encourage outbreaks of infectious diseases and spread pathogens.

Fact Sheet-Schistosomiasis (Centers for Disease Control and Prevention) - Information on diagnosis, treatment, and prevention of the disease schistosomiasis.

Games and Activities Games and Activities

Disease Detective (Public Broadcasting Services) - Interactive game investigating a disease outbreak at a national park in the American Southwest, playing the role of an epidemiologist.

Videos Videos

Water+?=Trouble Parts 1 - 5 (Thinkport) - Online video about water pollution and related illnesses, part 1.

For Teachers For Teachers

Activities: Hysteria Over Pfiesteria (U.S. Environmental Protection Agency) - Lesson plans designed to guide Middle schools students through investigations of Pfiesteria outbreaks.