Hepatitis B immunity in hospital staff targeted for vaccination. Role of screening tests in immunization programs

To estimate how many hospital workers might be exempted from immunization with newly available but expensive hepatitis B vaccine, baseline serum samples were analyzed to determine prevalence and titer of hepatitis B (HB) surface antibody (anti-HBs) and prevalence of core antibody (anti-HBc). Among 1,370 persons tested, anti-HBs was present in 279 (20.4%), including 192 (14.0%) with titers of 10 ratio units or greater. In a subset of 746 subjects who denied recent exposures, and who were tested for anti-HBc and anti-HBs, at least one of the two antibodies was found in 172 (23.1%). There were 47 (6.3%) who had anti-HBs alone and 27 (3.6%) with anti-HBc alone. Prevalence was related more closely to clinical service (eg, renal dialysis or surgery) than to title (eg, physician or technician).