JOHNSON COUNTY, Kan. -- The CDC says cases of cryptosporidium are growing across the country.
That's a parasite that can be transmitted via swimming pools and cause diarrhea for around two weeks.
"You have to ingest it to get the parasite," said Steve Vogelsang, an environmental health specialist for Johnson County.
So far, there haven't been any cases associated with pools in the metro, but there are a few things people can do to stay safe.
Vogelsang said parents should watch children closely at pools and water playgrounds to make sure they don't swallow the water. He inspects pools regularly, but he doesn't test for crypto unless an epidemiologist says there's a case associated with a particular pool.
"In a pool that is well maintained, crypto will last about 10 days before it dies out, and the pool will actually be safe again," Vogelsang said. "We would have them hyper chlorinate to 20 ppm and have them hold it that way for almost 13 hours."
Vogelsang said there haven't been any cases in Johnson County this summer, but two years ago, they shut down two HOA pools for cyptosporidium.
"It's always best not to swim until your diarrhea has stopped for two weeks," Vogelsang said.
People can also get crypto from animals. So if you pet an animal, especially cattle, wash your hands after. The CDC also says to keep kids with with diarrhea home -- and out of childcare.