[Intradermal hepatitis B vaccination in workers not responsive to intramuscular vaccination]

Health care workers are at continuous risk of hepatitis B infection. Currently recommended intramuscular vaccination confers immunity in only 85-90%. We examined the immunogenicity and safety of intradermal vaccination of hepatitis B vaccine in nonresponders. 400 hospital employees who had been immunized as recommended were screened for anti-HBs antibodies and 50 were found seronegative. Each received an intramuscular booster injection and antibody level was measured a month later. Excluded were 33 employees, including 24 late responders, 2 HbsAg carriers and 7 uncooperative employees. 17 employees (mean age 47.1 yrs) then received a series of 3 intradermal injections of Energix B, 0.25 ml in the forearm, 2-3 weeks apart. The mean number of previous intramuscular injections was 4.6 +/- 1.4. A month later there was a mean titer of 315.4 +/- 347.0 miu/ml of antibody in 16/17 workers. Side effects were minimal. Intradermal injection of hepatitis B vaccine for nonresponders seems effective for inducing seroconversion. Its cost-effectiveness for the health care system warrants assessment.