Persistence of the D variant of encephalomyocarditis virus in the ICR-Swiss mouse.

The D variant of encephalomyocarditis virus (EMCV-D) is used in the murine model to study virus-induced, acute-onset diabetes mellitus (IDDM) and myocarditis. In this model, viral replication and disease occur within seven days post infection (p.i.), and by Day 10 p.i., no infectious virus is detectable. The present study examined the possibility that EMCV-D persists in ICR-Swiss mice after the acute infection is resolved. The data show that viral antigen is detected at 28 days p.i. within the pancreatic islets of 8/10 males and 13/14 females, and within the heart valves of all animals tested. Histologic examination of the organs at 28 days p.i. suggests the development of chronic obstructive pancreatitis, and shows almost fully healed lesions in the myocardium. These observations indicate that the murine model for the study of EMCV-D induced IDDM may be extended to investigate chronic pancreatitis and heart-valve disease.