Long-term persistence of immunity after vaccination of pre-adolescents with low doses of a recombinant hepatitis B vaccine

Abstract

Background and aims: Recent studies have shown no detectable antibodies and no response to a challenge dose of vaccine 10–20 y after receiving low doses (2.5–5 µg) of recombinant hepatitis B vaccine during first months of life. Little information is available on long-term persistence of immunity after vaccinating pre-adolescents with low doses of hepatitis B vaccine.

Materials and Methods: This randomized trial was initiated in 1996 with the main objective to assess the persistence of antibodies and immune memory 5, 10 and 15 y after vaccinating 8–10 y-old children with three doses of Recombivax 2.5 µg, as well as the short and long-term effect of a booster dose given at different intervals.

Results: The results of 560 subjects were included in this analysis. All subjects had a seroprotective antibody titer (≥ 10 IU/L) one month post-primary vaccination; 5, 10 and 15 y post-vaccination 95%, 95% and 87% had detectable antibodies, and 82%, 86%, and 68% had a seroprotective antibody titer; GMTs were 73 IU/L, 89 IU/L, and 28 IU/L, respectively. More than 99.4% of subjects had an anamnestic response to a challenge dose of vaccine given 5, 10, or 15 y post-vaccination. Five and ten years post-booster dose 97% and 95% of subjects still have a seroprotective anti-HBs titer with GMTs 16–18-fold higher when compared with those observed 5–10 y post-primary vaccination.

Conclusions: Virtually all children vaccinated at the age of 8–10 y with low doses of hepatitis B vaccine still have an excellent immune memory up to age of 25 y. The results of this study do not support the use of booster doses.

Keywords: :

• hepatitis B
• immunity
• long term
• persistence
• vaccination

Disclosure of Potential Conflicts of Interest

No potential conflicts of interest were disclosed.

Acknowledgments

This study was initiated by Dr. Bernard Duval who prematurely passed away. The study was financially supported by Quebec Ministry of Health and Social Services. We are grateful to all study participants, to our research coordinators and research nurses, as well as to France Lavoie and Colette Couture for their dedication to this study realization.