title: [Vaccination against viral hepatitis A and B in adults aged over 40 years--antibody persistence and immune memory].
abstract: OBJECTIVE
  Primary vaccination with combined vaccine against viral hepatitis A (VHA) and viral hepatitis B (VHB) induces higher anti-hepatitis B surface (anti-HBs) antibody responses and similar anti-hepatitis A virus (anti-HAV) antibody responses in adults aged over 40 years in comparison with concomitant monovalent vaccines against VHA and VHB. Th e objectives were to assess, in a clinical study, persistence of anti-HAV and anti-HBs antibodies in adults aged over 40 years four years after primary VHA/VHB vaccination and antibody response following a booster dose of the vaccine.
  
  
  METHODS
  Five hundred and ninety-six subjects aged > 40 years were vaccinated with three doses of the combined VHA/VHB vaccine at Months 0, 1, 6 (HAB group) or with concomitant VHA and VHB vaccines at Months 0, 6 and 0, 1, 6 (ENG+HAV and HBVX+VAQ, respectively). Blood samples were collected one month following primary vaccination (Month 7) and then at one-year intervals for four years after the booster dose with the same vaccine as used for the primary vaccination. The anti-HBs and anti-HAV antibody levels were determined prior to the booster dose and at days 14 and 30 after the booster dose.
  
  
  RESULTS
  At Month 7, > 97% of study subjects were seropositive for anti-HAV antibodies in all groups analyzed. Four years after primary vaccination, anti-HAV antibody seropositivity persisted in > 93% of study subjects, increasing to > 99% after the booster dose. At Month 7, the highest proportion of study subjects with anti-HBs antibody levels > or = 10 mIU/ml was found in the HAB group (91.7% versus 79.7% in the ENG+HAV group versus 71.0% in the HBVX+VAQ group). Four years after vaccination, anti-HBs antibody levels of 10 mIU/ml persisted in 57.1% of the HAB study subjects in comparison with 40.1% and 26.6% of the study subjects in the ENG+HAV and HBVX+VAQ groups, respectively. One month after the booster dose, anti-HBs antibody levels increased and antibody levels > or = 10 mIU/ml was achived in 95.2% of study subjects in the HAB group, 90.5% in the ENG+HAV group and 85.3% in the HBVX+VAQ group.
  
  
  CONCLUSIONS
  In the adults aged over 40 years, an adequate anti-HAV antibody response persisted for at least four years after vaccination and was higher and more sustained in those who received the combined HAB vaccine. A strong antibody response to the booster dose indicative ofthe presence of immune memory was seen in all study groups.
authors: Katedra epidemiologie, Fakulta vojenského zdravotnictví Univerzity obrany, Hradec Králové. chlibek@pmfhk.cz
authors: R
authors: R
authors: Chlibek
authors: J
authors: J
authors: Smetana
authors: V
authors: V
authors: Bostíková
authors: M
authors: M
authors: Splino
mesh_terms: D000328:Adult; D005260:Female; D006506:Hepatitis A / Q000276:immunology* / Q000517:prevention & control; D035922:Hepatitis A Antibodies / Q000097:blood*; D006509:Hepatitis B / Q000276:immunology* / Q000517:prevention & control; D006510:Hepatitis B Antibodies / Q000097:blood*; D006801:Humans; D007117:Immunization, Secondary; D008297:Male; D008875:Middle Aged; D014611:Vaccination; D017778:Vaccines, Combined / Q000276:immunology; D014761:Viral Hepatitis Vaccines / Q000276:immunology*
chemical_list: D035922:Hepatitis A Antibodies; D006510:Hepatitis B Antibodies; D017778:Vaccines, Combined; D014761:Viral Hepatitis Vaccines