About Cryptosporidiosis

Key points

  • Cryptosporidiosis is a disease that causes watery diarrhea.
  • It is caused by a microscopic germ (parasite) called Cryptosporidium. This parasite can live in water, food, soil, or on surfaces that have been contaminated with infected poop.
  • Cryptosporidium can be found in the United States and throughout the world.
A close up image of two crypto germs as seen under a microscope


Cryptosporidiosis is a diarrhea-causing disease that is spread through germs that live in the poop of infected people or animals. When a person swallows Cryptosporidium, or "Crypto" germs, they can become infected.

Symptoms of cryptosporidiosis generally begin 2 to 10 days (average 7 days) after infection and last 1 to 2 weeks. The most common symptom of cryptosporidiosis is watery diarrhea, but some people have no symptoms at all.

Contact your healthcare provider if you suspect that you have cryptosporidiosis. Most people with healthy immune systems will recover from cryptosporidiosis without treatment.

The best way to prevent the spread of Cryptosporidium in the home is by practicing good hygiene. Wash your hands at key times with soap and water, especially after using the toilet, after changing diapers, and before eating or preparing food, drinks, or ice.