According to the Centers for Disease Control, recreational water illnesses are caused by contaminated water in things like swimming pools, water parks, lakes, rivers, or oceans.
Due to strong water testing regulations, its much harder to get sick at a pool than it used to be, but it's still possible.
Cryptosporidium, or "crypto", is one of the most frequent causes of waterborne disease among humans in the United States. It is the germ that causes diarrhea and can survive for days, even in properly chlorinated pools.
Swimmer's Ear is an infection of the outer-ear canal. It develops when contaminated water sits in the ear canal for a long period of time. It is a common problem that can cause pain and discomfort.
Doctors say to decrease the chances of an infection you should also never put pool water in your mouth.
And remember that chlorine kills germs, but things like sunlight, dirt, and swimmers can affect chlorine levels.
"The amount of chlorine in a pool, even from a small gulp of water won't hurt anyone. And many of the public pools and I think people need to be very careful at home as well that they have the proper balance of chlorine in their pools," said Dr. Lara Danzinger-Isakov of Cleveland Clinic Children's Hospital.
The CDC recommends staying out of the pool if you are sick with diarrhea and showering before and after swimming.