The most common symptom of Cryptosporidium is watery diarrhoea but other symptoms include abdominal pain, loss of appetite, fever, nausea, and vomiting. Symptoms generally begin 2 to 10 days after exposure and usually last about 1 to 2 weeks in immunocompetent people but there may be an occasional reoccurrence of symptoms which may come and go for up to 30 days. Individuals remain infectious for as long as visible oocytes are excreted in stool and certainly while diarrhoea is present. Generally, the infectivity period lasts for between 2 and 4 weeks but shedding may continue for up to 2 months after symptoms subside.