Protozoa: Cystoisospora belli (Syn. Isospora belli)

Cystoisospora belli is a coccidian protozoan parasite belonging to the phylum Apicomplexa. Many species of the genus infect a variety of animals such as dogs, cats, pigs, and nonhuman primates. Pathogenicity in man appears to be restricted to C. belli because many human infections that were in the past attributed to Isospora hominis are now thought to have been caused by Sarcocystis hominis or Sarcocystis suihominis, through the accidental ingestion of raw beef or pork, respectively. Cystoisospora belli has a cosmopolitan distribution, but is more common in the tropics. This parasite usually affect immunocompromised persons (e.g., acquired immunodeficiency syndrome patients), and the infection causes severe symptoms chronic cholera-like diarrhea. In the current article parasitological, clinical, and epidemiological aspects as well as the implications for food safety are discussed.