Cryptosporidium is a parasite that causes a diarrheal illness called cryptosporidiosis (the parasite and the disease are often called “Crypto”). Crypto is a common waterborne illness and is the most common cause of recreational water illness in the United States. How is it spread? Crypto is passed in the stool of an infected person or animal.
What is cryptosporidiosis?
Learn more about our editorial process. Cryptosporidiosis is an illness you get from the parasite Cryptosporidium. It causes watery diarrhea that can be severe. You can get it from contaminated water.
How is crypto transmitted?
Crypto is passed in the stool of an infected person or animal. The parasite is protected by an outer shell that allows it to survive outside the body for long periods of time, and is highly resistant to chlorine. Crypto can be transmitted by: Swallowing contaminated water while swimming or drinking.
