Five viruses have now been identified that each cause a different type of hepatitis, A through E. 2. The majority of people with viral hepatitis recover uneventfully; however, in some persons with HBV and HCV, a chronic carrier state develops that may persist for a lifetime. 3. Operating room nurses are at greatest risk for HBV if they are not immunized; they can prevent HBV by obtaining hepatitis B vaccine and adhering to standard OR practices plus using eye protection.