Intradermal hepatitis B vaccination in health care workers. Response rate and experiences from vaccination in clinical practise

Health care workers at risk for hepatitis B virus infection are recommended for vaccination. Low-dose intradermal (i.d.) administration of vaccine has been suggested as a Less expensive alternative to intramuscular (i.m.) ino culation. To evaluate the i.d, vaccination route, health care workers were included in a prospective study. The subjects were vaccinated with 0.1 mi ( =2 mu g) recombinant vaccine (Engerix B, SmithKline Beecham) i.d. at 0, 1 a nd 6 months. Two months after the third vaccination, measurement of the ant i-HBs level was conducted. An anti-HBs level greater than or equal to 10 IU /I was considered protective. Those with an anti-HBs level < 10 IU/l were g iven a fourth dose with new serological control after another 2 months. The results are based on the 1406 subjects that it was possible to evaluate. T he seroconversion rate to protective anti-HBs level after 3 doses was 68% a nd after 3 or 4 doses 89%. Factors associated with a lower response rate we re increasing age (p < 0.05) and smoking (p< 0.001). Sex or body mass index had no influence on the results. Vaccination technique seems to be of utmo st importance when the i.d. route is used. Well instructed and experienced nurses are required and quality control with follow-up of overall seroconve rsion rate within each centre is needed.