Sarcocystis nesbitti
![Sarcocysts isolated from persons infected with Sacrocystis nesbetti, Pangkor Island, Malaysia, 2012. A- Intact human sarcocyst (length 190 µm) with thin cyst wall (arrow) from homogenized temporalis tissue inoculated into a U937 monocytic cell culture (original magnification ×200, scale bar = 20 µm). B- Intramuscular sarcocyst enclosed by a thin smooth cyst wall (arrow) without any protrusions. Maximum cyst wall thickness is ≈0.5 µm (hematoxylin and eosin stained, original magnification ×40, scale bar = 10 µm).](/Images/godic/202502/09/Sacrocystis_nesbetti_sarcocysts4249.jpg")
Sarcocystis nesbitti is a species of protozoon.
An outbreak investigation was conducted on 93 symptomatic persons from Malaysia following a college retreat on January 17–19, 2012, on Pangkor Island. Predominant manifestations were fever (relapsing in ≈50% of patients), myalgia, headache, and cough. Although only 2 patients were confirmed to be acutely infected with S. nesbitti, it was likely that the remaining students and teachers in the group had the same infection because nearly all had similar signs and symptoms with onset of illness within days of each other. In addition, 9 patients had a distinctive facial myositis, but sarcocysts could not be verified in all of them because only 3 patients agreed to provide a muscle biopsy specimen.