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by Martin JJ


Cryptosporidiosis is an intestinal infection. It goes away on its own in most people. But, it can be life-threatening for young children, the elderly, and people who are sick.

The Intestines
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A certain parasite causes cryptosporidiosis. It enters the body by when you swallow it. Once in the intestine, it comes out of its shell and multiplies. You can get it from contaminated water, soil, or stool. It can pass to you from:

  • Water from lakes, streams, hot tubs, swimming pools, or water parks
  • Ice cubes
  • A baby's dirty diapers
  • Touching animals, cleaning cages, or going to barns or petting zoos
  • Eating food grown in soil
  • Eating or drinking unpasteurized dairy products
  • Oral to anal contact during sex

Risk Factors

Risk is higher for:

  • Young children, especially those in day care
  • Day care workers or those who work in a group setting
  • Backpackers, hikers, and campers who recreate in contaminated water sources
  • People whose immune system is weakened by cancer, HIV , or an organ transplant
  • People who have oral to anal contact during sex


Most people don’t have symptoms. If they do appear, they may cause:

  • Watery diarrhea
  • Belly cramps
  • Nausea or vomiting
  • Slight fever
  • Weakness
  • Weight loss
  • Dehydration


The doctor will ask about your symptoms and health history. You may have a physical exam and stool tests.


Most people will not need care because the infection will go away on its own. The infection is also more likely to be more severe and last longer if your immune system is weak.

If needed, care may involve:

  • IV fluids
  • Medicine to control diarrhea


To lower your chances of cryptosporidiosis:

Wash your hands often, mainly:

  • After using the toilet.
  • After changing a diaper.
  • Before handling or eating food.
  • After being with animals or in soil.
  • After being with people who are sick.

In general:

  • Use water you know is safe. If you have any doubts, don’t use it.
  • Try not to swallow while recreating in water.
  • Wash fruits and vegetables in safe water.
  • Don’t eat or drink unpasteurized dairy products.
  • Use barriers when you have oral sex.


Centers for Disease Control and Prevention 

IDSA—Infectious Diseases Society of America 


Canadian Public Health Association 

Health Canada 


Cryptosporidiosis. New York Department of Health website. Available at: Updated September 2016. Accessed May 29, 2018.

Parasites—cryptosporidium (also known as crypto). Centers for Disease Control and Prevention website. Available at: Updated January 12, 2017. Accessed May 29, 2018.

Foodborne illnesses. EBSCO DynaMed website. Available at:  . Updated May 23, 2018. Accessed May 29, 2018.

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