[Measurement of anti-HBs antibodies in a population of 18-year-olds 6 years after the primary vaccination series]. / Valutazione degli anticorpi anti-HBs in un campione di diciottenni a 6 anni dal ciclo vaccinale primario.

We have analized the persistence of vaccine-induced antibodies to hepatitis B surface antigen, in a cohort of 445 eighteen-year-old males, who had been immunized against hepatitis B six years earlier (when they were 12 years old, according to the Italian law). These young men were about to begin their military service and were going through the routine check-up. They came from two different towns Reggio Emilia and Mantova, in the north of Italy, and were divided into two groups (group A no 258 men, group B no 187 men) depending on where they had been vaccinated. The serologic results showed that 97% of subjects had anti-HBs and 94% anti-HBs protective levels (> or = 10 mIU/ml). Moreover 81% of responder subjects showed titles > or = 100 mIU/ml, and 25% showed titles even > or = 1000 mIU/ml. Anti-HBs GMT of the total responders was 367.1. Differences have been found in the anti-HBs levels of men vaccinated in the two different towns.