title: Differences in response to a hepatitis B vaccine booster dose among Alaskan children and adolescents vaccinated during infancy.
abstract: BACKGROUND
  The duration of protection provided by hepatitis B vaccination is unknown, but the presence of immune memory can be evaluated indirectly by measuring the immune response to a booster dose of vaccine.
  
  
  METHODS
  Participants included 74 adolescents (aged 11.7-14.9 years) who had received a plasma-derived 3-dose primary vaccine series and 138 adolescents (aged 10.0-14.7 years) and 166 children (aged 5.0-7.0 years) who received a recombinant 3-dose primary vaccine series. All were born to hepatitis B surface antigen-negative mothers and had received the first dose of hepatitis B vaccine within 7 days of birth. The proportion of participants with serologic evidence of protective immunity (antibody to hepatitis B surface antigen > or = 10 mIU/mL) at baseline (prebooster), the proportion who developed an anamnestic response (increase to > or = 10 mIU/mL or at or more than fourfold increase in antibody to hepatitis B surface antigen to > 10 mIU/mL), and the geometric mean concentration by 1, 2, and 4 weeks after a 5-microg recombinant vaccine booster dose were determined.
  
  
  RESULTS
  No participant had evidence of chronic hepatitis B virus infection. Overall, 99% of the group of children who received recombinant hepatitis B vaccine, 83% of the group of adolescents who received recombinant hepatitis B vaccine, and 69% of the group of adolescents who received the plasma-derived vaccine had an anamnestic response to a booster dose; among responders, the geometric mean concentration at 2 weeks postbooster was 3360 and 128 mIU/mL among adolescents who received plasma-derived vaccine with antibodies to hepatitis B surface antigen > or = 10 and < 10 mIU/mL at baseline, respectively, compared with 1283 and 369 mIU/mL among adolescents who received recombinant hepatitis B vaccine and 5091 and 696 mIU/mL for children who received recombinant hepatitis B vaccine. The anamnestic response rate at 2 weeks postbooster among participants with antibodies to hepatitis B surface antigen < 10 mIU/mL at baseline was inversely associated with age; 97% of 5-year-olds responded compared with 60% of 14-year-olds.
  
  
  CONCLUSIONS
  Although most participants responded to a booster dose of hepatitis B vaccine, the significance of the increased proportion of nonresponses among older adolescents might indicate waning immune memory.
authors.affiliation: Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
authors.forename: Taraz
authors.initials: T
authors.lastname: Samandari
authors.forename: Anthony E
authors.initials: AE
authors.lastname: Fiore
authors.forename: Susan
authors.initials: S
authors.lastname: Negus
authors.forename: James L
authors.initials: JL
authors.lastname: Williams
authors.forename: Wendi
authors.initials: W
authors.lastname: Kuhnert
authors.forename: Brian J
authors.initials: BJ
authors.lastname: McMahon
authors.forename: Beth P
authors.initials: BP
authors.lastname: Bell
mesh_terms: D000293:Adolescent; D000413:Alaska / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005500:Follow-Up Studies; D006509:Hepatitis B / Q000453:epidemiology / Q000276:immunology* / Q000517:prevention & control*; D006510:Hepatitis B Antibodies / Q000096:biosynthesis* / Q000097:blood; D006514:Hepatitis B Surface Antigens / Q000008:administration & dosage / Q000276:immunology; D017325:Hepatitis B Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D006515:Hepatitis B virus / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007115:Immunization Schedule; D007117:Immunization, Secondary; D007231:Infant, Newborn
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines