Cryptosporidiosis

Cryptosporidiosis
Micrograph showing cryptosporidiosis. The cryptosporidium are the small, round bodies in apical vacuoles on the surface of the epithelium. H&E stain. Colonic biopsy.
Specialty	Infectious disease
Symptoms	Watery diarrhea, nausea, abdominal pain, fever
Causes	Cryptosporidium infection
Risk factors	Immunocompromisation
Prevention	Avoid contaminated water
Treatment	Nitazoxanide

Cryptosporidiosis, sometimes informally called crypto,^[1] is a parasitic disease caused by Cryptosporidium, a genus of protozoan parasites in the phylum Apicomplexa. It affects the distal small intestine and can affect the respiratory tract in both immunocompetent (i.e., individuals with a normal functioning immune system) and immunocompromised (e.g., persons with HIV/AIDS or autoimmune disorders) individuals, resulting in watery diarrhea with or without an unexplained cough.^[2] In immunosuppressed individuals, the symptoms are particularly severe and can be fatal. It is primarily spread through the fecal-oral route, often through contaminated water;^[2][3] recent evidence suggests that it can also be transmitted via fomites contaminated with respiratory secretions.^[2]

Cryptosporidium is commonly isolated in HIV-positive patients presenting with diarrhea.^[4][5] Despite not being identified until 1976, it is one of the most common waterborne diseases and is found worldwide. The infection begins when a human consumes food or water containing cysts of the Cryptosporidium organism.^{[citation needed]}