Human and animal sarcocystosis in Malaysia: A review

Sarcocystosis is a zoonotic disease caused by a coccidian intracellular protozoan parasite of the genus Sarcocystis. More than 200 Sarcocystis species have been recorded and the parasites are found in mammals, birds and reptiles. They require two hosts to complete their life cycle. In Malaysia, sarcocystosis was reported as a potential emerging food and water-borne disease after a series of large outbreak of human infections. There was not enough attention given before even though it was reported in both humans and animals. The first human case of invasive muscular sarcocystosis among local Malaysian was reported in 1975. Besides, a retrospective autopsy examination on 100 tongues revealed 21% positive cases. On top of that, a sero-epidemiological survey conducted in 243 subjects in West Malaysia showed that 19.7% had Sarcocystis antibodies. The clinical symptoms of muscular sarcocystosis were first described comprehensively in 1999. Meanwhile, many types of animals including livestock were found harbor the sarcocysts in their tissue. The first case of human intestinal sarcocystosis was reported in 2014. This review indicates that human sarcocystosis is currently endemic in Malaysia and parallel to that reported in animals. However, more studies and investigations need to be conducted since the source of human infection remains unknown.