Cryptosporidiosis is a disease caused by a parasite called Cryptosporidium parvum . Cryptosporidiosis was responsible for a large drinking water outbreak of diarrheal disease in Milwaukee, Wisconsin in 1993. Anyone, but it may be more common in persons with impaired immune systems and in children in daycare centers. Cryptosporidium is found in the digestive systems of infected animals and humans. Any pet, farm animal or wild animal, including birds, fish, and reptiles, can become infected.
Calves are the most likely animals to be infected.
People or animals become infected by swallowing the oocysts. This can occur after touching stools from infected humans or animals or after handling objects contaminated with infected stool material. Unwashed hands can then transfer the oocysts to the mouth. Persons and animals can also become infected by drinking water or eating raw or undercooked food contaminated with stool material from infected animals or humans. Some people have become sick after swimming in public pools contaminated with stools from infected persons.