What is it?
Cryptosporidium parvum, also known as crypto, is a microscopic protozoa that can cause a parasitic disease in the intestines of mammals, including humans. It is considered the most significant waterborne pathogen in developed countries. In fact, it sickened 403,000 people in Milwaukee, Wisconsin in 1993. The protozoa itself is protected by a thick outer shell that keeps it alive outside the body for long periods; it is also chlorine resistant.
How is it spread?
Cryptosporidium is typically spread by drinking contaminated water, eating infected food, or being contaminated by feces. It only takes two to ten cryptosporidium parasites to cause infection.
Typical Symptoms
Symptoms include acute, non-bloody diarrhea, nausea, vomiting, abdominal pain, fatigue, and loss of appetite.
Most at risk
Young children, pregnant women, the elderly, and immunocompromised persons are most at risk, but given the right conditions, anyone can suffer this illness.
For more information, see:
http://en.wikipedia.org/wiki/Cryptosporidium_parvum
http://www.cdc.gov/parasites/crypto/
http://www.foodborneillness.com/cryptosporidium_food_poisoning/