Illness & Symptoms

Symptoms of cryptosporidiosis generally begin 2 to 10 days (average 7 days) after becoming infected with the parasite. The most common symptom of cryptosporidiosis is watery diarrhea. Symptoms include:

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

Some people with Crypto will have no symptoms at all.

Symptoms usually last about 1 to 2 weeks (with a range of a few days to 4 or more weeks) in persons with healthy immune systems. Occasionally, people may experience a recurrence of symptoms after a brief period of recovery before the illness ends. Symptoms can come and go for up to 30 days.

While the small intestine is the site most commonly affected, in immunocompromised persons Cryptosporidium infections could possibly affect other areas of the digestive tract or the respiratory tract.

People with weakened immune systems may develop serious, chronic, and sometimes fatal illness. Examples of people with weakened immune systems include:

  • people with HIV/AIDS;
  • those with inherited diseases that affect the immune system; and
  • cancer and transplant patients who are taking certain immunosuppressive drugs.

The risk of developing severe disease may differ depending on each person’s degree of immune suppression.