Cryptosporidium infection

Cryptosporidium infection (cryptosporidiosis) is an illness caused by tiny 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 of your intestines. Later, cryptosporidia are shed in your feces.

In most healthy people, a cryptosporidium infection produces a bout of watery diarrhea and 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 proper treatment.

You can help prevent a cryptosporidium infection by practicing good hygiene and avoiding swallowing water from pools, recreational water parks, lakes and streams.

Symptoms Causes Risk factors Complications Prevention

The first signs and symptoms of cryptosporidium infection usually appear within a week after infection and may include:

  • Watery diarrhea
  • Dehydration
  • Lack of appetite
  • Weight loss
  • Stomach cramps or pain
  • Fever
  • Nausea
  • Vomiting

Symptoms may last for up to two weeks, though they may come and go sporadically for up to a month, even in people with healthy immune systems. Some people with cryptosporidium infection may have no symptoms.

When to see a doctor

Seek medical attention if you develop watery diarrhea that does not get better within a few days.

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