A family outbreak of cryptosporidiosis: Probable nosocomial infection and person-to-person transmission.

Cryptosporidium is an important cause of community gastroenteritis, usually associated with drinking contaminated water, visits to swimming pools or animal exposure. In immunocompetent patients, cryptosporidiosis is usually a self-limiting disease but it can be devastating illness in immunocompromised persons. This report presents a family outbreak of cryptosporidiosis and describes a probable nosocomial infection with Cryptosporidium in one patient and subsequent spread of the parasite among members of his family. The index patient, a 72-year-old man with hemiparesis after his third stroke, died after 28 days of persistent diarrhea. Control measures must be undertaken to prevent nosocomial transmission of cryptosporidial oocysts.