MYRTLE BEACH, SC (WBTW) – The CDC warns Americans about the swimming pool parasite called cryptosporidium this year, and says the number of cases have increased, on average, almost 13% between 2009 and 2017.

Grand Strand Medical infectious diseases Dr. Nick Powers saw one case of cryptosporidiosis last year. It’s a fecal parasite that can fester in swimming pools.

“This germ is unique because it being a parasite, it has an outer shell to it, and because of that, chlorine doesn’t even really kill this germ effectively,” said Dr. Powers.

Dr. Powers says although the germ can’t be killed by pool chemicals, there is one way to ward off the germ.

“Soap and water and good, old-fashioned elbow grease and scrubbing tend to work the most,” he laughed.

Those with HIV or suppressed immune systems are more likely to get the symptoms of the parasite, but if you get crypto and you’ve got a strong immune system, that’s a good thing.

“It’ll come and go, presents with diarrheal illness for about maybe two days at most,” said Dr. Powers. “Most people recover on their own, because their immune system is able to kind of neutralize the parasite so to speak.”

Dr. Powers says although he hasn’t seen any crypto cases this year, he predicts one or two will pop up in South Carolina before the summer is over.

“Even though we have a lot of pools here, because it is close to the beach, you know, we really don’t have a higher percentage here than we would anywhere else in the country,” he said.

The germ can congregate, so it’s important to replace pool filters often, especially in public pools. Because children’s immune systems aren’t the strongest yet, the kiddie pool is where you’ll often find the parasite.

“Particularly where we worry about it with children is because if they can’t control their bowels when they’re around like the kiddie pool, or something like that, this can get into the water, and because chlorine doesn’t kill it, then it can be spread in that manner,” said Dr. Powers.

He says some people can actually be carriers for the crypto germ, and only show symptoms of the illness if their immune system is suppressed.