title: Greater antibody responses to an eleven valent mixed carrier diphtheria- or tetanus-conjugated pneumococcal vaccine in Filipino than in Finnish or Israeli infants.
abstract: BACKGROUND
  Antibody responses to pneumococcal conjugate vaccines may vary when administered in different populations or epidemiologic settings. Understanding the causes and significance of this variation could help to determine the number of doses and timing required for protection against pneumococcal diseases in each country.
  
  
  METHODS
  This report compares antibody responses to aluminum-adjuvanted and nonadjuvanted mixed carrier 11-valent diphtheria- or tetanus-conjugated pneumococcal vaccine (11-PncTD) formulations when given at 6, 10 and 14 weeks and 9 months of age to Filipino infants (n = 51) and at 2, 4, 6 and 12 months of age to Finnish (n = 127) and Israeli (n = 124) infants. The study populations differ in their natural exposure to pneumococcus and risk factors for pneumococcal carriage and disease.
  
  
  RESULTS
  Filipino and Israeli infants had slightly but significantly higher prevaccination geometric mean concentration (GMC) of antibodies than did the Finnish infants. After three doses of aluminum-adjuvanted 11-PncTD vaccine, the Filipino infants had 1.8 to 6.7 and 1.5 to 5.0 times higher GMC than the Finnish and Israeli infants, respectively, against pneumococcal serotypes conjugated to tetanus protein. The GMC of serotypes conjugated to diphtheria toxoid was 1.3 to 3.0 and 0.7 to 2.0 times the GMC in Finnish and Israeli infants, respectively. The nonadjuvanted vaccine formulation induced generally lower GMCs.
  
  
  CONCLUSIONS
  The antibody responses to the tetanus-conjugated polysaccharides were considerably higher in the Filipino than in the Finnish or Israeli infants. This may be a result of several factors including the priming effect of tetanus toxoid given to pregnant women, early pneumococcal nasopharyngeal acquisition and genetic differences among populations.
authors.affiliation: Department of Vaccinology, National Public Health Institute, Helsinki, Finland. taneli.puumalainen@ktl.fi
authors.forename: Taneli
authors.initials: T
authors.lastname: Puumalainen
authors.forename: Ron
authors.initials: R
authors.lastname: Dagan
authors.forename: Tomi
authors.initials: T
authors.lastname: Wuorimaa
authors.forename: Rose
authors.initials: R
authors.lastname: Zeta-Capeding
authors.forename: Marilla
authors.initials: M
authors.lastname: Lucero
authors.forename: Jukka
authors.initials: J
authors.lastname: Ollgren
authors.forename: Helena
authors.initials: H
authors.lastname: Käyhty
authors.forename: Hanna
authors.initials: H
authors.lastname: Nohynek
mesh_terms: D000907:Antibodies, Bacterial / Q000276:immunology*; D000917:Antibody Formation / Q000276:immunology; D002353:Carrier State / Q000276:immunology*; D004165:Diphtheria / Q000276:immunology* / Q000517:prevention & control; D022422:Diphtheria-Tetanus Vaccine / Q000008:administration & dosage / Q000276:immunology*; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005387:Finland; D006801:Humans; D007115:Immunization Schedule; D007223:Infant; D007557:Israel; D008297:Male; D010679:Philippines; D011008:Pneumococcal Infections / Q000276:immunology* / Q000517:prevention & control; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000276:immunology*; D012680:Sensitivity and Specificity; D013742:Tetanus / Q000276:immunology* / Q000517:prevention & control; D014611:Vaccination / Q000379:methods; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D022422:Diphtheria-Tetanus Vaccine; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate