The aetiology of MSGS has not been fully elucidated, although multiple
infectious agents have been observed in several organs by histopathology,
transmission electron microscopy (TEM), and
polymerase chain reaction (PCR) methods (Chayaburakul et al.,
2004; Anantasomboon et al., 2006). Most significantly, multiple
spheroids were observed in the lymphoid organs and shown to
contain several viruses of known and unknown types (Anantasomboon
et al., 2006; Sritunyalucksana et al., 2006).