title: Immunogenicity of a Haemophilus influenzae type b-tetanus conjugate vaccine when administered separately or in combined vaccines for primary immunization in two consecutive national schedules in Turkey.
abstract: BACKGROUND
  In Turkey, the Haemophilus influenzae type b-tetanus toxoid conjugate vaccine (Hib) was replaced by the combined diphtheria-tetanus-acellular pertussis and inactivated polio vaccine (DTaP-IPV/Hib) in 2008. This shift to the new schedule created different cohorts of vaccinated children as a consequence of the different schedules used. We evaluated the immunogenicity of the Hib vaccine in infants vaccinated with these different schedules.
  
  
  METHODS
  Three groups of children were evaluated: group 1 comprised 145 infants vaccinated with diphtheria, tetanus, and whole cell pertussis (DTwP), oral polio vaccine (OPV), and Hib vaccines simultaneously at separate sites; group 2 comprised 204 infants vaccinated with the DTaP-IPV/Hib combined vaccine; group 3 comprised 100 infants vaccinated with a mixed schedule of DTwP, OPV, and Hib for the first one or two doses, followed by DTaP-IPV/Hib vaccine to complete the series.
  
  
  RESULTS
  Anti-polyribosylribitol phosphate (anti-PRP) titers ≥0.15μg/ml were similar in groups 1, 2, and 3. However, in group 1, who received all the vaccines at separate sites, ≥ l.0μg/ml long-lasting antibody titers and anti-PRP geometric mean titers were higher (p=0.001).
  
  
  CONCLUSIONS
  This study showed that even one dose administered in combination with other vaccines in a primary series decreased the level of anti-PRP.
authors.affiliation: Department of Pediatrics, Gazi University Medical Faculty, Ankara, Turkey.
authors.forename: Nurullah
authors.initials: N
authors.lastname: Yüksel
authors.forename: Ufuk
authors.initials: U
authors.lastname: Beyazova
authors.forename: Işil Fidan
authors.initials: IF
authors.lastname: Balci
authors.forename: Fatma Nur
authors.initials: FN
authors.lastname: Aksakal
authors.forename: Aysu Duyan
authors.initials: AD
authors.lastname: Camurdan
authors.forename: Figen
authors.initials: F
authors.lastname: Sahin
authors.forename: Seyyal
authors.initials: S
authors.lastname: Rota
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood; D004168:Diphtheria Toxoid / Q000008:administration & dosage; D006192:Haemophilus Infections / Q000517:prevention & control*; D018073:Haemophilus Vaccines / Q000008:administration & dosage* / Q000276:immunology; D019741:Haemophilus influenzae type b / Q000276:immunology*; D006801:Humans; D007223:Infant; D032541:Mass Vaccination; D010567:Pertussis Vaccine / Q000008:administration & dosage; D011054:Poliovirus Vaccine, Inactivated / Q000008:administration & dosage; D011134:Polysaccharides / Q000276:immunology; D011159:Population Surveillance; D013745:Tetanus Toxoid / Q000008:administration & dosage; D014421:Turkey; D022282:Vaccines, Acellular / Q000008:administration & dosage; D017778:Vaccines, Combined / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D004168:Diphtheria Toxoid; D018073:Haemophilus Vaccines; D010567:Pertussis Vaccine; D011054:Poliovirus Vaccine, Inactivated; D011134:Polysaccharides; D013745:Tetanus Toxoid; D022282:Vaccines, Acellular; D017778:Vaccines, Combined; C008984:polyribitol phosphate