Encephalomyocarditis (EMC) virus infection in the common vole, Microtus arvalis

Encephalomyocarditis (EMC) virus infection in the common vole was examined for the first time. Sixteen 8-week-old males inoculated intraperitoneally with 105plaque-forming units (pfu)/animal of the D variant of EMC virus were killed 3 and 7 days after inoculation (3 and 7 DAI). Viral replication was detected in the brain (105pfu/g), heart (104pfu/g) and pancreas (107pfu/g) of all 8 animals at 3DAI. It was found in the pancreas (103pfu/g) of all 8 animals and in the brain (104pfu/g) of 2 of 8 animals at 7 DAI. Histopathological changes were observed in the brain (mild mononuclear cell infiltration around capillaries and sporadic pyknosis of neurons), heart (minimal myocardial necrosis) and pancreas (prominent acinar cell necrosis with inflammatory exudation) at 3DAI. At 7 DAI, replacement of necrotic tissues by mesenchymal cells and regeneration of acinar cells were conspicuous in the pancreas. Throughout the experimental period, no evidence for diabetogenic effect was found.