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5/14/24 Public Health Education Topic: Cryptosporidium

Per CDC:

Cryptosporidiosis is a disease that causes watery diarrhea. It is caused by microscopic germs—parasites called Cryptosporidium. Cryptosporidium, or “Crypto” for short, can be found in water, food, soil or on surfaces or dirty hands that have been contaminated with the feces of humans or animals infected with the parasite. During 2001–2010, Crypto was the leading cause of waterborne disease outbreaks, linked to recreational water in the United States. The parasite is found in every region of the United States and throughout the world.

How is cryptosporidiosis spread?

Crypto lives in the gut of infected humans or animals. An infected person or animal sheds Crypto parasites in their poop. An infected person can shed 10,000,000 to 100,000,000 Crypto germs in a single bowel movement. Shedding of Crypto in poop begins when symptoms like diarrhea begin and can last for weeks after symptoms stop. Swallowing as few as 10 Crypto germs can cause infection.

Crypto can be spread by:

  • Swallowing recreational water (for example, the water in swimming pools, fountains, lakes, rivers) contaminated with Crypto

  • Crypto’s high tolerance to chlorine enables the parasite to survive for long periods of time in chlorinated drinking and swimming pool water

  • Drinking untreated water from a lake or river that is contaminated with Crypto

  • Swallowing water, ice, or beverages contaminated with poop from infected humans or animals

  • Eating undercooked food or drinking unpasteurized/raw apple cider or milk that gets contaminated with Crypto

  • Touching your mouth with contaminated hands

  • Hands can become contaminated through a variety of activities, such as touching surfaces or objects (e.g., toys, bathroom fixtures, changing tables, diaper pails) that have been contaminated by poop from an infected person, changing diapers, caring for an infected person, and touching an infected animal

  • Exposure to poop from an infected person through oral-anal sexual contact

Crypto is not spread through contact with blood.

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