Infection of mice with the murine coronavirus mouse hepatitis virus (MHV) provides a model for studying acute virus-induced neurological disease as well as providing a model for chronic demyelinating diseases, such as multiple sclerosis. Following intracranial (i.c.) inoculation, MHV-A59 replicates in the central nervous system (CNS) and causes acute encephalitis, which peaks at about 7 days postinfection (12); virus is cleared from the CNS by 7 to 14 days postinfection (27). Following clearance, surviving mice develop an immune-mediated demyelinating disease (12), which peaks at about 30 days postinfection