STOCKTON, Calif. — Eleven-year-old Raeana Rosander loves to hang out at the pool.

“I enjoy swimming and making new friends,” Rosander said.

We met her at the Oak Park Pool, 3754 Alvarado Ave., in Stockton. She has no worries that the water is safe. But recently, the Centers for Disease Control [CDC] issued a warning that cases for the waterborne parasite Cryptosporidium, or Crypto, are on the rise.

Crypto, which is caused by swallowing contaminated water in pools or water playgrounds, can lead to “life-threatening malnutrition” for those with weakened immune systems. According to the CDC, Crypto is the leading cause of outbreaks of diarrhea linked to water and the third leading cause of diarrhea associated with animal contact in the United States.

“It can cause watery diarrhea, some nausea, vomiting, achy stomach and if you’re having a lot of diarrhea, it can cause dehydration if you’re not getting enough fluids,” Dr. Kismet Baldwin, San Joaquin County Health Officer, said. “It can be in lakes, in streams, in rivers and also can be in pools and fountains. And, if you swallow the water, that’s how you can become infected."

In 2017, San Joaquin County had its own outbreak of Crypto with 33 cases. So far through 2019, there have been four reported cases. The San Joaquin County Environmental Health Department oversees the testing, inspection and safety of close to 650 of the county’s public pools, spas, water features and more. They test chlorine and PH levels, but not for Crypto.

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Crypto is resistant to chlorine and is more difficult to kill than most disease-causing germs. Individual cities like Stockton do their own testing. At the Oak Park Pool, life guards test the water every two hours for chlorine and PH levels, but again, not for Crypto.

“I think any public pool, you’re always concerned about any foreign material, Crypto, fecal matter, bacterial matter,” Stephen Jiang, Deputy Director of Community Services Recreation for Stockton, says. “We test our pools and treat our pools daily. We can have a high level of assurance that they’re safe.”

So, how can you protect yourself against getting the nasty parasite? Baldwin suggests if you or your child has diarrhea, keep out of pools or other recreational water features.

“Try not to swallow any of the water in the pools or the rivers and lakes and places like that,” Baldwin said.

She says if you are camping, purify the water by boiling it to kill any sign of Crypto.

“Diligent, diligent hand washing with soap and water because the alcohol-based hand sanitizers do not kill Crypto," Baldwin said. "So, that’s not going to protect you."

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