Cryptosporidium muris oocysts found in human feces.
Classification and external resources
Cryptosporidiosis, also known as crypto,
is a parasitic disease caused by Cryptospor-
idium, a protozoan parasite in the phylum
Apicomplexa. It affects the intestines of mam-
mals and is typically an acute short-term in-
fection. It is spread through the fecal-oral
route, often through contaminated water;
the main symptom is self-limiting diarrhea in
people with intact immune systems. In im-
munocompromised individuals, such as AIDS
the symptoms are particularly
severe and often fatal. Cryptosporidium is
the organism most commonly isolated in HIV
positive patients presenting with diarrhea.
Treatment is symptomatic, with fluid rehyd-
ration, electrolyte correction and manage-
ment of any pain. Despite not being identified
until 1976, it is one of the most common wa-
terborne diseases and is found worldwide.
The parasite is transmitted by environment-
ally hardy cysts (oocysts) that, once ingested,
excyst in the small intestine and result in an
infection of intestinal epithelial tissue.
Cryptosporidium is a protozoan pathogen of
the Phylum Apicomplexa and causes a
diarrheal illness called cryptosporidiosis.
Other apicomplexan pathogens include the
malaria parasite Plasmodium, and Toxo-
plasma, the causativ