Recreational Water Illness

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Children in swimming pool

Recreational water illnesses (RWIs) are caused by germs and chemicals found in the water we swim in. RWIs can be involve your stomach, intestines, skin, ears, respiratory system, eyes, or nervous system. The most commonly reported RWI is diarrhea. Swallowing just a mouthful of water that contains diarrhea-causing germs can make you sick. Other germs that cause RWIs can be spread by having contact with or breathing in mists of contaminated water.


Key Facts

  • The most common RWI is diarrhea. Swallowing water contaminated with poop that contains germs can cause diarrheal illness.
  • Diarrheal illnesses can be caused by germs such as Cryptosporidium, Giardia, Shigella, norovirus, and E. coli.
  • People have an average of 0.14 grams of poop on their bottoms. This poop can wash off swimmers’ bodies and can contaminate the water with germs.
  • RWIs can also be caused by chemicals in the water or chemicals that enter the air from the water.


Mobile App

Mobile App

Help keep yourself and your family healthy and safe this summer swim season and all year round. If you are a pool inspector, operator or lifeguard, you can have the latest information at your fingertips to answer patron questions. We all share the water we play and swim in. Learn about the germs that we all bring into the places we swim, how they could make you and others sick, and how you can take a few easy and effective steps to help protect yourself and loved ones. Go to iTunes to download CDC’s Healthy Swimming app.

Children playing in water fountain

Interactive Fountains

Although there is no standing water in attractions such as interactive fountains or water play areas, the spray water will rinse any contaminants (for example, diarrhea, vomit, and dirt) off of users and down into the water holding area to be sprayed again. In other words, the water is recycled through the system. As a result, it is possible for the water to become contaminated and cause outbreaks of illness.

Video Thumbnail of Healthy Swimming play video

Video Thumbnail of RWI Prevention - Video Contest Winner play video

Video thumbnail of In the Swim of Things play video

Prevention Tips

We all share the water we swim in, and we each need to do our part to keep ourselves, our families, and our friends healthy. To help protect yourself and other swimmers from germs, here are a few simple and effective steps all swimmers can take each time we swim:

  • Keep the pee, poop, sweat, and dirt out of the water!
  • Stay out of the water if you have diarrhea.
  • Shower before you get in the water.
  • Don’t pee or poop in the water.
  • Don’t swallow the water.
  • Take kids on bathroom breaks every hour.
  • During breaks, check diapers, and change them in a bathroom or diaper-changing area–not poolside–to keep germs away from the pool.
  • Reapply sunscreen and drink plenty of fluids.

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Page last reviewed: June 6, 2017