Cryptosporidium infection (cryptosporidiosis) is an illness caused by tiny, one-celled cryptosporidium parasites. When cryptosporidia (krip-toe-spoe-RID-e-uh) enter your body, they travel to your small intestine and then burrow into the walls. Later, they're shed in your feces.
In most healthy people, a cryptosporidium infection produces a bout of watery diarrhea. The infection usually goes away within a week or two. If you have a compromised immune system, a cryptosporidium infection can become life-threatening without treatment.
You can help prevent a cryptosporidium infection by practicing good hygiene and avoiding swallowing water from pools, recreational water parks, lakes and streams.
The first signs and symptoms of cryptosporidium infection, which usually appear within a week after infection, might include:
Symptoms can last for up to two weeks, though they might come and go for up to a month, even in people with healthy immune systems. Some people with cryptosporidium infection have no symptoms.
Seek medical attention if you develop watery diarrhea that does not get better within a few days.
Cryptosporidium infection begins when the one-celled cryptosporidium parasites get into your body through your mouth. Some strains of cryptosporidium can cause more serious disease.
These parasites then travel to your intestinal tract, where they settle into the walls of your intestines. Eventually, more cells are produced and are shed in massive quantities into your feces, where they are highly contagious.
You can become infected with cryptosporidia by touching anything that has come in contact with contaminated feces. You can get infected by:
If you have a compromised immune system from HIV/AIDS, you're more susceptible to illness from cryptosporidium parasites than is a person with a healthy immune system. People with HIV/AIDS can develop severe symptoms and a chronic, persistent form of disease that can be difficult to treat.
Cryptosporidium parasites are one of the more common causes of infectious diarrhea in humans. This parasite is difficult to to get rid of because it's resistant to many disinfectants and many filters don't remove it.
Cryptosporidia can survive for months at varying temperatures, though the parasite can be destroyed by boiling.
People who are at increased risk of developing cryptosporidiosis include:
Complications of cryptosporidium infection include:
Cryptosporidium infection isn't life-threatening. However, if you've had a transplant or if you have a weakened immune system, developing complications can be dangerous.
Cryptosporidium infection is contagious, so take precautions to avoid spreading the parasite to other people. There's no vaccine to prevent a cryptosporidium infection.
To help prevent cryptosporidium infection:
Purify drinking water if you have a weakened immune system or are traveling in an area with a high risk of infection. Methods include boiling — at least one minute at a rolling boil — or filtering, although filtering might not be as effective as boiling.
Be sure to use a filter that meets the NSF International standard 53 or 58 requirements for cyst and oocyst reduction. You'll need a separate water filter for bacteria and viruses.
Always avoid swimming when you have diarrhea. If you know you've had a cryptosporidium infection, don't go swimming for at least two weeks after your symptoms go away because you can still be contagious.
The following tests can diagnose cryptosporidium infection:
Most healthy people with cryptosporidiosis recover within two weeks without treatment.
If you have a compromised immune system, the treatment goal is to relieve symptoms and improve your immune response. Cryptosporidiosis treatment options include:
You're likely to start by seeing your family doctor. In some cases, he or she may refer you to a doctor who specializes in infectious diseases or a doctor who specializes in disorders of the gastrointestinal tract (gastroenterologist).
Here's some information to help you get ready for your appointment.
Make a list of:
For cryptosporidiosis, basic questions to ask your doctor include:
Don't hesitate to ask other questions.
Your doctor is likely to ask you questions, such as:
While you're waiting to see your doctor, drink plenty of fluids.
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