IMMUNOGENICITY OF LOW-DOSE INTRADERMAL RECOMBINANT-DNA HEPATITIS-B VACCINE

Low-dose intradermal vaccination with plasma-derived hepatitis B vaccine has been shown to give high rates of seroconversion at greatly reduced vaccine cost. We report a study comparing two groups given lower doses (1.0 or 1.5-mu-g) of recombinant-derived vaccine intradermally with a control group given the standard intramuscular dose. Of the 132 randomized medical students and hospital employees, 95 completed the study. Rates of seroconversion and peak antibody titers were comparable, though antibody rose more slowly and fell somewhat faster in the intradermal groups. Increasing the intradermal dose did not improve response. Most intradermal vaccinees (80%) developed small (average 2 to 3 mm) areas of local induration, which faded slowly. Low-dose intradermal vaccination with recombinant hepatitis B vaccine results in high rates of seroconversion (> 90% in each protocol) at a cost that will allow individual practitioners and program with limited budgets to offer vaccination.