Progress toward the elimination of hepatitis B virus transmission among health care workers in the United States.
BACKGROUND: Hepatitis B virus (HBV) infection is a well-recognized occupational risk for health care workers (HCWs). Vaccination coverage, disease trends, and the need for booster doses after hepatitis B vaccination of adults have been the subject of intense study during the 15 years of the vaccine's availability. METHODS: Vaccination coverage of HCWs was determined from a review of medical records on a sample of employees from 113 randomly selected hospitals. The number of HBV infections among HCWs and the general US population for 1983 through 1995 was estimated from national surveillance data. Studies on long-term protection after hepatitis B vaccination of adults were reviewed. RESULTS: A total of 2837 employee medical records were reviewed; 2532 employees (90%) were eligible to receive hepatitis B vaccine, and 66.5% of them (95% confidence interval, 61.9%-70.9%) had received 3 doses of hepatitis B vaccine. Vaccination coverage was highest (75%) for personnel with frequent exposure to infectious body fluids (phlebotomists, laboratory personnel, and nursing staff) and lowest (45%) for employees at low risk for exposure (dietary and clerical staff). The number of HBV infections among HCWs declined from 17,000 in 1983 to 400 in 1995. The 95% decline in incidence observed among HCWs is 1.5-fold greater than the reduction in incidence in the general US population. Studies on long-term protection demonstrate that vaccine-induced protection persists at least 11 years even when titers of antibody to hepatitis B surface antigen decline below detectable levels. CONCLUSIONS: Although a high percentage of HCWs have been fully vaccinated with hepatitis B vaccine, efforts need to be made to improve this coverage. There has been a dramatic decrease in the number of HBV infections among HCWs who are now at lower risk of HBV infection than the general US population. Vaccine-induced protection persists at least 11 years and booster doses are not needed at this time for adults who have responded to vaccination.