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Cryptosporidium Parasite

Swimming-related illnesses are diseases people can get from the water in pools, hot tubs, or spas – if that water is contaminated with germs. Germs can mean bacteria or parasites. You can get a swimming-related illness if you swallow, have contact with, or breathe in aerosols from contaminated water. This can also include lakes, rivers, and oceans. The most common symptoms are diarrhea, skin rashes, ear pain, cough or congestion, and eye pain. Diarrheal illnesses can be caused by germs such as Cryptosporidium, Giardia, Shigella, norovirus, and E. coli.

According to the Centers for Disease Control and Prevention (CDC), Cryptosporidium (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. 35% of those outbreaks were associated with pools.

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What Is Crypto?

Cryptosporidium is a parasite that can cause nausea, diarrhea, abdominal pains, and vomiting. Most people recover, but to those with compromised immune systems, it may be life-threatening. This parasite causes issues for hot tubs, spas, and swimming pools as it is resistant to chlorine at the levels usually found in pools, spas, and hot tubs and can survive in swimming pool waters for over ten days.

How Does Cyrptosporium Spread?

Crypto is spread by contacting water contaminated with human feces infected with the parasite. Someone with the Cryptosporidium protozoa in their gut will produce large numbers of the oocysts in their feces. Even after the symptoms of cryptosporidiosis disappear, the oocysts might be present in feces for at least another fourteen days. Did you know that raccoons, opossums, birds, and other animals can also infect the water with pathogens and parasites?

Preventing Crypto

Normal sanitizers used to disinfect pools, such as chlorine, cannot kill this parasite. According to Dr. Rajapakse of the Mayo Clinic, “The troublesome thing about the Cryptosporidium parasite is that it is surrounded with a protective capsule. This makes it resistant to the usual levels of chlorination that we use in swimming pools. There are special procedures pools have to do called hyperchlorination if they are found to have this infection spreading through their pool.”

The CDC offers these guidelines:

  • Stay out of the water if you are sick with diarrhea.
  • If you have been diagnosed with Crypto, don’t go back in the
    water until two weeks after diarrhea completely stops.
  • Don’t poop in the water.
  • Don’t swallow the water.
  • Take kids on bathroom breaks or check diapers every hour.
  • Change diapers away from the water to keep germs from
    getting in the water.
  • Shower before entering the pool, spa, or hot tub

Treating Your Pool, Spa, or Hot Tub

Because chlorine won’t kill off the Cryptosporidium oocysts, the only way to get rid of them is by using an effective pool filtration system. A single flow of water through filters is often insufficient to remove every oocyst. Ozone and ultraviolet light can eliminate parasites and bacteria. Ozone is a strong oxidizer that can kill bacteria on contact. Contact or call us for more information on UV and ozone systems.

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