The epidemiology of hepatitis B infection in housestaff.

Ninety-nine medical and surgical house officers were prospectively evaluated during internship and residency for the development of hepatitis B virus (HBV) infection. The overall incidence of hepatitis B was 10.2% per year. Eighty-six percent of episodes were subclinical. The greatest risk factor appeared to be frequent hand-to-mouth activity such as smoking or licking requisition labels. The presence of a hemodialysis or transplantation unit may be an additional institutional risk factor. HBV infection was not associated with a history of needle-sticks or contact with known antigen-positive patients. Educational efforts to minimize HBV infection should concentrate on handwashing techniques and discouragement of hand-to-mouth activity in patient care areas.