HEPATITIS-B VACCINE IMMUNORESPONSIVENESS IN ADOLESCENTS - A REVACCINATION PROPOSAL AFTER PRIMARY VACCINATION

Hepatitis B recombinant vaccine immunoresponsiveness was studied in 42 7 preadolescents vaccinated with a 0, 1 and 6 months vaccination sched ule. AntiHBs postvaccination titres (measured one month after the last dose) were related to the following variables: sex, weight, height, a nd Quetelet index. The antiHBs postvaccination titres were used to pre dict the length of protection induced by the vaccine. AN preadolescent s developed antiHBs titres 10 IU l(-1) and no statistically significan t differences could be found between sexes. The relation study between antiHBs postvaccination levels and Quetelet index showed a statistica lly significant inverse correlation According to the antiHBs postvacci nation titres, the central 50% of the sample distribution would be pro tected during a period between 7.5 and 10.5 years. In pre-teenagers, t he hepatitis B recombinant vaccine has proven to be highly immunogenic , obesity is a predictor of poor immunoresponse and this response is n ot influenced by sex. According to our. results, we would propose the administration of a single booster dose 10 years after primary vaccina tion and thus protect these subjects during the period of greatest ris k.