Cryptosporidiosis, or crypto, is an intestinal infection caused by the cryptosporidia parasite. The parasite can be found in every region of the United States and throughout the world. According to the Center for Disease Control, in the United States, crypto is one of the leading causes of waterborne disease outbreaks linked to recreational water like pools.

Here are some of the most commonly asked questions about the diagnosis, treatment, and prevention of cryptosporidiosis.

  1. How is cryptosporidiosis spread? Cryptosporidiosis infection spreads through the oral-fecal route. The parasite is shed through the feces of an infected person or animal, which can then contaminate food or water supplies. People contract crypto when they swallow contaminated water, particularly from recreational water sources like pools, lakes, or rivers. Crypto can also be spread through ingesting unwashed or undercooked food contaminated with the parasite.
  2. What are the symptoms of cryptosporidiosis? Cryptosporidiosis symptoms include watery diarrhea, stomach cramps, dehydration, nausea, vomiting, fever, and weight loss. People typically begin to show symptoms of cryptosporidiosis about 7 days after becoming infected, and symptoms of cryptosporidiosis typically last between 1-2 weeks in people with healthy immune systems. Cryptosporidiosis is not dangerous for people with healthy immune systems, but may cause serious or even life-threatening complications in immuno-compromised people.
  3. How is cryptosporidiosis diagnosed? Since the cryptosporidia parasite is shed in an infected person’s feces, stool samples are used to diagnose the disease. Doctors will often take multiple stool samples on different days to ensure the accuracy of the test results.
  4. How is cryptosporidiosis typically treated? Most healthy people will recover from cryptosporidiosis without any kind of treatment. Rather than curing the infection, recommended treatments for cryptosporidiosis instead tend to focus on alleviating the symptoms; these include drinking plenty of fluids to prevent dehydration and getting plenty of rest. Over-the-counter anti-diarrheal medications may help alleviate diarrhea, but patients should consult with their doctor before taking these medicines. In addition, the FDA has approved nitazoxanide for the treatment of diarrhea caused by cryptosporidiosis in people with healthy immune systems; again, you will need to consult with your doctor to obtain a prescription.
  5. How can I prevent cryptosporidiosis infection? Proper hygiene is crucial in preventing the spread of cryptosporidiosis. Make sure to wash your hands thoroughly with warm water and soap after using the bathroom or changing a diaper and before and after preparing food. Also thoroughly wash all fruits and vegetables prior to eating, and make sure to thoroughly cook meat products. If you are traveling in a developing region, avoid raw foods and drink only filtered or purified water. In addition, take care when swimming in public pools or in rivers or lakes to avoid ingesting potentially contaminated water.
  6. What kinds of tests are used to test for cryptosporidiosis? Stool samples will be used to detect cryptosporidiosis antigens. The most common cryptosporidiosis antigen test is an enzyme-linked immunosorbent assay (ELISA), like the IVD Cryptosporidiosis Stool Antigen Detection Microwell ELISA.


Center for Disease Control (CDC). “Cryptosporidium (also known as Crypto)”. Available at
Mayo Clinic. “Cryptosporidium Infection.” Available at