Crypto, A Fecal Parasite Often Spread By Swimming, Is Causing An Increase In Illness Outbreaks, CDC Says

The Centers for Disease Control and Prevention (CDC) is warning people about a parasite called Cryptosporidium (also known as Crypto) found in pools or water playgrounds.

Crypto is not spread through contact with blood. Rather, Cryptosporidium infection (cryptosporidiosis) is an illness caused by tiny, cryptosporidium parasites that live in water. When the parasites enter your body, they travel to your small intestine and burrow into your intestinal walls. Later, the parasites are shed through your poop, says Mayo Clinic.

According to a CDC report released in June, outbreaks of Crypto in the United States increased about 13 percent each year from 2009 to 2017. There were 444 outbreaks reported from 2009 through 2017, which resulted in nearly 7,500 illnesses, 287 hospitalizations and one death.

In the United States, more than half of all recent Crypto-related illnesses are associated with swimming pools, water playgrounds and other water recreation areas, since people tend to swallow water in these places.

Since Crypto is protected by an outer shell, it can actually survive for days in the chlorinated water of pools and water playgrounds. And with these places being the go-to's for those trying to cool themselves in the hot weather, infections are most common in July and August, the CDC says.

In most healthy people, Crypto produces a bout of diarrhea, and the infection usually clears within two weeks. But if you have a compromised immune system, Crypto can be life-threatening without proper treatment. Other symptoms include stomach cramps, nausea, vomiting and fever. You may avoid contracting Crypto by practicing good hygiene and avoiding swallowing water from pools, recreational water parks, lakes and streams, according to the Mayo Clinic.

Other Crypto outbreaks have been linked to cattle farms, childcare centers and consumption of unpasteurized milk and apple cider, the CDC says.

"Young children can get seriously sick and easily spread Crypto," says Michele Hlavsa, chief of the CDC's Healthy Swimming Program. "They don't know how to use the toilet and wash their hands, or are just learning how. But we as parents can take steps to help keep our kids healthy in the water, around animals, and in childcare."

No person should swim if they are sick with diarrhea, and all swimmers should also take care not to swallow water, according to the CDC. Also, sick children should be kept home from school or childcare; people, particularly those who are in contact with animals, should wash their hands often; and people should avoid drinking unpasteurized milk or apple cider.

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Children swim in one of the pools at the Munsu Water Park. Carl Court/Getty Images

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