Before you take another dip in the pool, the Centers for Disease Control and Prevention has a warning about something that could make you very sick.

Outbreaks of a parasitic infection linked to swimming pools and water playgrounds are on the rise — doubling in just two years.

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Crypto outbreaks: What you need to know

New data published in CDC’s Morbidity and Mortality Weekly Report has revealed that at least 32 outbreaks caused by Cryptosporidium (Crypto for short) linked to pools in the U.S. were reported in 2016, compared with 16 outbreaks in 2014.

Health officials don’t know if the problem is getting worse or if the increase is simply due to better reporting.

The CDC says the parasite can spread when people swallow something that has come into contact with the feces of a sick person, such as pool water contaminated with diarrhea.

Unfortunately, Crypto isn’t easily killed by chlorine and can survive up to 10 days in well-treated pools.

“Swallowing just a mouthful of water contaminated with Crypto can make otherwise healthy people sick for up to three weeks with watery diarrhea, stomach cramps, nausea, or vomiting, and can lead to dehydration,” the CDC said.

To protect yourself and others from Crypto and other diarrhea-causing germs, follow the CDC’s advice:

• Don’t swim or let your kids swim if sick with diarrhea
• Don’t swallow the water in which you swim
• Rinse off in the shower before getting in the water to help remove any germs on your body that could contaminate the water
• Take kids on bathroom breaks often, and check diapers in a diaper-changing area and not right next to the pool

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