Immunoresponse to routine hepatitis B vaccination in pre-adolescents in the province of Guadalajara, Spain

Background: Although hepatitis B vaccine has been available in Spain since 1986, acute and chronic hepatitis B virus infection remains a public health problem. The comprehensive national strategy to prevent hepatitis B virus transmission includes hepatitis B vaccination of pre-adolescents. Our objective was to investigate the immuno-response to routine hepatitis B vaccination in pre-adolescents in the province of Guadalajara and to study the relationship between the immunoresponse and other variables such as height, weight, Quetelet index, sex and home environment (rural or urban). Methods: We considered a cross-sectional descriptive study in the school population of eighth year primary education. Hepatitis B recombinant vaccine immunoresponsiveness was studied in 338 students vaccinated with a 0, 1 and 6 months vaccination schedule. Anti-hepatitis B post-vaccination titres were quantified considering levels of protection ≥10 UI I−1. Results: The seroprotection rate was 97, 6%. The response of more than 46% of the children was very satisfactory and their anti-hepatitis B post-vaccination titres exceeded 1000 UI I−1. No statistically significant differences could be found between sexes. The relation study between anti-hepatitis B post-vaccination levels and Quetelet index showed a statistically significant inverse correlation (p