Long-term Immunogenicity and Immune Memory After Two Doses of the Adult Formulation of a Combined Hepatitis A and B Vaccine in Children 1 to 11 Years of Age

Abstract

Long-term persistence of antibodies against hepatitis A and B (anti-HAV and anti-HBs) were evaluated in 1- to 11-year-old children following 2 doses (0, 6 months) of hepatitis A and B vaccine. Ten years postvaccination, all subjects were anti-HAV seropositive (≥15 mIU/mL), 81.7% had anti-HBs antibody concentrations ≥10 mIU/mL. All subjects with anti-HBs concentrations <10 mIU/mL, mounted a vigorous anamnestic response to an HBV vaccine challenge dose indicating the presence of immunologic memory against hepatitis B.