Evaluación de la respuesta serológica a la vacuna contra la hepatitis B en una población laboral hospitalariaThe effectiveness of hepatitis B vaccine was evaluted in 120 employees at the National Children`s Hospital of San José, Costa Rica, who enter voluntarily in the vaccination programme during the 1995-1996 period. The vaccination results were found successful in 99,13% of the persons studied, showing seroprotection response levels of ant-HBs antibodies higher than 10 mUI/ml. It was found that age and sex had a direct influence on the seroconvertion levels reached, observing that young people and women were better responders.