Etiology:  Reovirus is a nonenveloped RNA virus of the family Reoviridiae.

Incidence:  The incidence of infection is rare in laboratory mice.

Transmission:  Transmission occurs through the oral-fecal route, direct contact, contact with fomites and aerosol routes.

Clinical Signs:  Mice naturally infected with REO-3 do not usually display clinical signs.

Diagnosis:  Diagnosis with REO-3 is usually made by serology (MFI, IFA) or PCR.