ARCHIVED - Measuring Long-Term Immunity After Hepatitis B Vaccination in Pre-Teens

Category: Viral Vaccines or Infections

Duval B, Gilca V, Boulianne N, De Serres G, DeWals P, Massé R,
Trudeau G

Background

A few years after immunization, anti-HBs titres disappear in many subjects. Immune memory usually persists, but a booster dose may be needed at some point. The long-term effect of a booster dose on hepatitis B immunity is unknown. We have studied the kinetics of antibodies 1 month and 5 years after the primary vaccination, and 1 month and 1 year after a booster dose.

Methods

Anti-HBc and anti-HBs were measured in 560 subjects 1 month and 5 years after vaccination at age 9 with Engerix-B (EB) 10 µg or Recombivax-HB (RB) 2.5 µg (schedule 0, 1, 6 months). A booster was given at age 14 and anti-HBs measured 1 month and 1 year later.

Results

All subjects were seprotected 1 month after the primary vaccination with three doses of vaccine. Titres decreased after 5 years to < 10 mIU/mL in 12.6% of EB and 18.4% of RB subjects. One month after the booster, titre of = 10 mIU/mL was present in > 99% of subjects. One year later, this proportion dropped to 98.5%; the GMTs were 14,028 in EB and 3,437 mUI/mL in RB groups. These GMTs were twice higher in EB group and similar in RB group when compared to those obtained 1 month after the primary vaccination.

Conclusion

Five years after vaccination, almost all teenagers were protected against hepatitis B despite the loss of antibodies. The booster dose was well tolerated and substantially increased the proportion of subjects with high titres. In most subjects the titres remained very high 1 year after the booster.