Sarcocystis
[sahr″ko-sis´tis] a genus of coccidian protozoa parasitic in birds, reptiles, and mammals, including humans, cattle, horses, sheep, swine, and rabbits and other rodents, occurring as elongated cylindrical bodies (sarcocysts) in the host's muscles. They have an obligatory two-host life cycle, involving sexual reproduction in the definitive host (a carnivore) and asexual reproduction, including schizogony and sarcocyst formation, which occurs in the intermediate host. Infection is transmitted by ingestion of the sporocysts in the feces passed by infected animals. See also
sarcocystosis.
Sarcocystis boviho´minis a species for which cattle are the specific intermediate hosts and humans the definitive hosts; it causes intestinal
sarcocystosis in humans. It was formerly considered to be combined with
S. suihominis in a single species,
S. hominis (
Isospora hominis).
Sarcocystis lindeman´ni a species causing human infection, most cases of which are asymptomatic, although it may cause polymyositis sometimes associated with eosinophilia.
Sarcocystis suiho´minis a species for which swine are the specific intermediate hosts and humans the definitive hosts; it causes intestinal
sarcocystosis in humans. It was formerly considered to form a single species with
S. bovihominis, called
S. hominis (
Isospora hominis).
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.