Immune response to recombinant b vaccine in school aged children under field conditions

The immunogenicity and reactogenicity of a recombinant hepatitis B vaccine was evaluated in 792 healthy 12 years olds. Three doses were administered (time 0,1,6 months); blood samples and self administered questionaries on reactogenicity were collected in a 9 month period. At the time of the first vaccine injection anti-HBc was detected in only three (0.37%) of the subjects. A protective antibody titer (>10mIU/ml) was present in 781 (98.6%) at 9 months (Geometric Mean Titer, GMT, 2951mIU/ml). Only mild local reactions and rare general symptoms were noted. These data confirme the safety and efficacy of this vaccination in Italian adolescents.