Intradermal hepatitis B virus vaccine: immunogenicity and side-effects in adults.

Fourteen adult volunteers were given a series of three 0.1 ml (2.0 micrograms of antigen protein) intradermal doses of hepatitis B virus vaccine (Merck). An antibody (anti-HBs) response was induced in 10 of 12 (83%) who were antibody negative at the start of the study. Two participants who had anti-HBs before vaccination had a significant increase in serum antibody. The two participants with no antibody response were the oldest members of the study group. Side-effects of the vaccine were limited to local reactions at the site of administration.