title: Comparison of a fifth dose of a five-component acellular or a whole cell pertussis vaccine in children four to six years of age.
abstract: OBJECTIVE
  Acellular pertussis vaccines are now preferred for all five childhood immunization doses; however, there are few data on the safety and immunogenicity of five consecutive doses. This study compared a fifth dose of an acellular and a whole cell pertussis vaccine in 4- to 6-year-old children previously immunized with four doses of acellular or whole cell pertussis vaccine.
  
  
  METHODS
  In a double blind, multicenter study, 366 healthy children were randomly allocated to receive a single injection of a 5-component acellular or a whole cell pertussis vaccine, each combined with diphtheria and tetanus toxoids and inactivated poliovirus vaccine.
  
  
  RESULTS
  Although injection site redness > or =50 mm and swelling > or =50 mm were common in children who had received five doses of acellular (50% and 48.1%, respectively) or whole cell (66.2% and 59.7%) pertussis vaccine, limb soreness and limitation of motion were less frequently reported after acellular (1.9% and 0%) than after whole cell (49.2% and 36.3%; P < 0.0001) pertussis vaccine. Pre-fifth dose antipertussis antibody titers were higher in children who previously had received four doses of acellular pertussis vaccine. Postimmunization antibody titers against pertussis toxin, filamentous hemagglutinin, pertactin and tetanus toxin were higher in recipients of five doses of acellular pertussis vaccine, whereas antibody titers to diphtheria toxin, pertussis fimbriae and poliovirus serotypes were higher in recipients of five doses of the whole cell pertussis vaccine (P < 0.05 for all comparisons).
  
  
  CONCLUSIONS
  A regimen consisting of five doses of a five-component acellular pertussis combination vaccine is safe and immunogenic in pre-school children. Local adverse reactions are common but are less painful and activity-limiting than a regimen of five doses of a whole cell pertussis vaccine.
authors.affiliation: Dalhousie University, Halifax, Canada. shalperin@iwkgrace.ns.ca
authors.forename: S A
authors.initials: SA
authors.lastname: Halperin
authors.forename: D
authors.initials: D
authors.lastname: Scheifele
authors.forename: L
authors.initials: L
authors.lastname: Barreto
authors.forename: C
authors.initials: C
authors.lastname: Pim
authors.forename: R
authors.initials: R
authors.lastname: Guasparini
authors.forename: L
authors.initials: L
authors.lastname: Medd
authors.forename: W
authors.initials: W
authors.lastname: Meekison
authors.forename: B J
authors.initials: BJ
authors.lastname: Eastwood
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D000914:Antibodies, Viral / Q000097:blood; D001886:Bordetella pertussis / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines; D004311:Double-Blind Method; D006801:Humans; D007115:Immunization Schedule; D007117:Immunization, Secondary; D010567:Pertussis Vaccine / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D011054:Poliovirus Vaccine, Inactivated / Q000008:administration & dosage / Q000276:immunology; D014611:Vaccination / Q000009:adverse effects; D017778:Vaccines, Combined / Q000276:immunology; D018074:Vaccines, Conjugate / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology*; D014917:Whooping Cough / Q000517:prevention & control
chemical_list: D000907:Antibodies, Bacterial; D000914:Antibodies, Viral; D015721:Diphtheria-Tetanus-Pertussis Vaccine; D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines; D010567:Pertussis Vaccine; D011054:Poliovirus Vaccine, Inactivated; D017778:Vaccines, Combined; D018074:Vaccines, Conjugate