RESUMO
BACKGROUND: Hepatitis B comprises one of the major health problems worldwide. One of the measures for the prevention thereof is the massive vaccination of adolescents. The purpose of our study is that of assessing the degree of coverage of the systematic hepatitis B prevention campaign among the 8th-grade population in the province of Guadalajara in addition to studying the immune response of said population, relating said response to other variables. METHODS: Cross-sectional study. The degree of coverage of the vaccination campaign was studied throughout the entire target population in the province in question. For the study of the immune response, a sample of 338 students was taken by systematic random sampling. The titres of anti-HB's were quantified 6 months following the third dosage, levels of 10 mU/ml or above being considered as being levels providing protection. RESULTS: The percentage of students properly vaccinated totaled 82.7%. The overall serum protection rate was 97.5%, and 46.7% of the sample responded showing titres of over 100 mU/ml. A statistically significant inverse relationship (p < 0.001) existed between the level of anti-HB's and the Quetelet level, we not having found any significant differences between the two sexes on comparing the postvaccination titres of anti-HB's. CONCLUSIONS: We consider the degree of coverage provided to be satisfactory and the immunogenic aspect of the vaccine to be good. Obesity is a factor providing a prior indication of a minor response to the same. This response is not influenced by the subject's sex.
