To the Editor.
—It is widely held that there is an increased incidence of hepatitis B among house-staff members. Lewis et al1 have demonstrated a significantly elevated rate of hepatitis B antibody (anti-HBs) in medical personnel as compared to controls (matched for several factors) chosen from among National Institutes of Health and other government employees. We attempted to determine if patient-physician contact was the route for acquisition of anti-HBs. A sample group of freshman and sophomore medical students (virtually no patient contact) was compared to junior and senior medical students and then to house officers and medical faculty (progressively increasing patient contact), to determine the pattern of anti-HBs acquisition.Blood samples were drawn from 497 individuals. No surgical residents or their faculty were included. The sera were tested by solid phase radioimmunoassay for the presence of hepatitis B antigen (HBsAg)2 and by passive