title: Recurrence of extensive injection site reactions following DTPa or dTpa vaccine in children 4-6 years old.
abstract: OBJECTIVE
  The aim of this study was to compare the immunogenicity and reactogenicity of a lower dose diphtheria, tetanus and pertussis vaccine (dTpa) with the recommended vaccine (DTPa) given as a fifth dose to 4-6-year old children who previously experienced an extensive injection site reaction (ISR).
  
  
  METHODS
  Children aged 4-6 years who had experienced an extensive ISR following a 4th dose of DTPa were recruited and randomly assigned to receive either the recommended DTPa or the lower dose dTpa vaccine. Parents recorded local reactions and systemic events for 15 days following vaccination. Immunogenicity was assessed pre and post vaccination by ELISA for diphtheria (D), tetanus (T), pertussis toxin (PT), filamentous haemagglutinin (FHA), and pertactin (PRN).
  
  
  RESULTS
  A total of 53 participants were vaccinated. There was a 72% recurrence rate of ISR, with a trend (p=0.055) towards fewer ISR in the dTpa (61.5%) compared with the DTPa group (85.2%). There was no difference in reports of pain or irritability between groups. All participants had seroprotective levels of antibody to D and T and seroresponse to each of the 3 pertussis antigens following vaccination with higher GMCs in DTPa vs dTpa group. There was no increase in antibody avidity observed post vaccination, regardless of vaccine given.
  
  
  CONCLUSIONS
  Recurrence of ISR with the 5th dose of diphtheria, tetanus and pertussis vaccination in children who have previously experienced an extensive ISR is high. Vaccination with a dTpa vaccine may reduce the risk of fifth dose ISR.
authors.affiliation: Discipline of Paediatrics, Women's and Children's Hospital, Part of the Children, Youth and Women's Health Service, South Australia, Australia.
authors.forename: Patrick
authors.initials: P
authors.lastname: Quinn
authors.forename: Michael
authors.initials: M
authors.lastname: Gold
authors.forename: Jenny
authors.initials: J
authors.lastname: Royle
authors.forename: Jim
authors.initials: J
authors.lastname: Buttery
authors.forename: Peter
authors.initials: P
authors.lastname: Richmond
authors.forename: Peter
authors.initials: P
authors.lastname: McIntyre
authors.forename: Nick
authors.initials: N
authors.lastname: Wood
authors.forename: Su-San
authors.initials: SS
authors.lastname: Lee
authors.forename: Helen
authors.initials: H
authors.lastname: Marshall
mesh_terms: D002648:Child; D002675:Child, Preschool; D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D005260:Female; D006801:Humans; D007117:Immunization, Secondary / Q000009:adverse effects* / Q000379:methods; D008297:Male; D012008:Recurrence; D012871:Skin Diseases / Q000139:chemically induced* / Q000453:epidemiology*; D014611:Vaccination / Q000009:adverse effects* / Q000379:methods
chemical_list: D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines