title: Antibody persistence six years after two doses of combined hepatitis A and B vaccine.
abstract: Persistent immunity to hepatitis A and hepatitis B antibodies six years after vaccination of adolescents (aged 12-15 years) with a combined hepatitis A and B (HAB) vaccine following a 0, 6 month or a 0, 12 month schedule was assessed. Yearly (Year-2-6) serum samples were tested for anti-HAV and anti-HBs using EIA. Subjects with anti-HBs concentrations <10 mIU/mL (14/23) at Year-5 or Year-6, received an additional HBV vaccine dose approximately 12 months after Year-6. Blood samples were collected pre-booster and 1 month post-booster to assess booster response. 240 subjects were vaccinated in the study; at Year-6, data were available from 88 subjects. At that time 84.8% (39/46; 0, 6 month) and 92.9% (39/42; 0, 12 month) of subjects had anti-HBs concentrations > or = 10 mIU/mL. All but one of the 14 boosted subjects responded to the additional HBV vaccine dose with anti-HBs concentrations > or = 100 mIU/mL. All seroconverted subjects who returned at Year-6 were seropositive for anti-HAV. Simplification, reduced number of doses and similar long-term persistence of immunity make the 0, 6 month and 0, 12 month schedule preferable for immunization against HAV/HBV in this population.
authors.affiliation: Centre for Immunization Research, The Children's Hospital at Westmead, Cnr Hainsworth Street and Hawkesbury Road, Locked Bag 4001, Westmead, Sydney, NSW 2145, Australia.
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Burgess
authors.affiliation: Centre for Immunization Research, The Children's Hospital at Westmead, Cnr Hainsworth Street and Hawkesbury Road, Locked Bag 4001, Westmead, Sydney, NSW 2145, Australia. Electronic address: peterm@chw.edu.au.
authors.forename: Peter B
authors.initials: PB
authors.lastname: McIntyre
authors.affiliation: Centre for Population Health, Burnet Institute, Commercial Road, Melbourne 3004, Australia.
authors.forename: Margaret
authors.initials: M
authors.lastname: Hellard
authors.affiliation: Nossal Institute for Global Health, University of Melbourne, Victoria 3010 Australia.
authors.forename: Tilman A
authors.initials: TA
authors.lastname: Ruff
authors.affiliation: GlaxoSmithKline, Biologicals, Rixensart, Belgium.
authors.forename: Inge
authors.initials: I
authors.lastname: Lefevre
authors.affiliation: GlaxoSmithKline, Biologicals, Rixensart, Belgium.
authors.forename: Hans L
authors.initials: HL
authors.lastname: Bock
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D035922:Hepatitis A Antibodies / Q000097:blood*; D022362:Hepatitis A Vaccines / Q000276:immunology*; D006510:Hepatitis B Antibodies / Q000097:blood*; D017325:Hepatitis B Vaccines / Q000276:immunology*; D006801:Humans; D007117:Immunization, Secondary / Q000379:methods*; D008297:Male; D013997:Time Factors; D014611:Vaccination / Q000379:methods*; D017778:Vaccines, Combined / Q000276:immunology*; D055815:Young Adult
chemical_list: D035922:Hepatitis A Antibodies; D022362:Hepatitis A Vaccines; D006510:Hepatitis B Antibodies; D017325:Hepatitis B Vaccines; D017778:Vaccines, Combined