Press Release

August 5, 2010


State Health Department Taking Precautions at Madison, Monroe and St. Clair County Pools  

Intense chlorination called for to contain outbreak of illness

SPRINGFIELD, Ill. – In an effort to protect the public’s health, the Illinois Department of Public Health (IDPH) is asking all swimming facilities in Madison, Monroe and St. Clair counties to hyperchlorinate all pools, spas and water park features. The Department closed a swimming pool in St. Clair County earlier this week after reports of several cases of cryptosporidiosis, a disease caused by a parasite in fecal matter that is sometimes found in pools. Department staff is visiting numerous pools in the metro east area today to educate facilities about the need for hyperchlorination and proper procedures. The Department has reports of four confirmed cases of cryptosporidiosis and local health department officials are investigating dozens of suspected cases.

“People who swam in the pool associated with the cryptosporidiosis cases, may have ingested the parasite through pool water, but have not yet developed symptoms. If those swimmers have since gone to a neighboring swimming pool or water park in the area, there is the potential they may have inadvertently contaminated the other pool,” Illinois Department of Public Health Director Dr. Damon T. Arnold said. “As a precaution, the Illinois Department of Public Health is asking all swimming facilities in Madison, Monroe and St. Clair counties to temporarily close and increase the amount of chlorine to high enough levels to kill the parasite and make the pools safe for swimming.”

The parasite, Cryptosporidium, or crypto for short, is spread in swimming pools when an ill person, or someone who has had diarrhea with the past two weeks, contaminates the water with fecal matter, and another person accidentally swallows that water. Most germs are killed by chlorine, but germs like crypto, are resistant to chlorine and can live in pools for days. Even the best maintained pools can spread illnesses if someone with diarrhea has entered the water.

Symptoms of cryptosporidiosis include watery diarrhea, abdominal cramping, nausea, vomiting, fatigue, weight loss and low-grade fever. Symptoms usually occur about a week after exposure, but can begin as soon as one day or as late as 12 days after exposure. Symptoms can last for up to 30 days in people who are otherwise healthy.

If you have recently been swimming and are experiencing illness, check with your doctor and alert your local health department right away.

For more information on healthy swimming and hyperchlorination, log onto

Procedure for Hyperchlorination in Public Swimming Facilities

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Illinois Department of Public Health
535 West Jefferson Street
Springfield, Illinois 62761
Phone 217-782-4977
Fax 217-782-3987
TTY 800-547-0466
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