Symptoms of Crypto infection can begin two to ten days after becoming infected with the parasite. Watery diarrhea is the most common symptom. Other symptoms include: stomach cramps or pain, dehydration, nausea, vomiting, fever, and weight loss.
In persons with healthy immune systems, symptoms usually last about one to two weeks. Some people with Crypto will have no symptoms at all. People with weakened immune systems, including those with HIV/ AIDS and transplant recipients, may be very ill for a much longer period of time and can have serious complications.