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How are RWIs spread?

Keep in mind that you share the water with everyone else in the pool, lake, or ocean.

Diarrheal Illnesses

If swimmers are ill with diarrhea, the germs that they carry can contaminate the water if they have an "accident" in the pool. On average, people have about 0.14 grams of feces on their bottoms which, when rinsed off, can contaminate recreational water. When people are ill with diarrhea, their stool can contain millions of germs. Therefore, swimming when ill with diarrhea can easily contaminate large pools or waterparks. In addition, lakes, rivers, and the ocean can be contaminated by sewage spills, animal waste, and water runoff following rainfall. Some common germs can also live for long periods of time in salt water.

So, if someone swallows water that has been contaminated with feces, he/she may become sick. Many of these diarrhea-causing germs do not have to be swallowed in large amounts to cause illness.

Other RWIs

Many other RWIs (skin, ear, eye, respiratory, neurologic, wound, and other infections) are caused by germs that live naturally in the environment (water, soil). In the pool or hot tub, if disinfectant is not maintained at the appropriate levels, these germs can increase to the point where they can cause illness when swimmers breathe or have contact with water containing these germs.

See also: Health Promotion Materials


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Content Source: Division of Parasitic Diseases, National Center for Zoonotic, Vector-borne, and Enteric Diseases
Page last modified: May 23, 2007