title: Effect of needle size on immunogenicity and reactogenicity of vaccines in infants: randomised controlled trial.
abstract: OBJECTIVE
  To assess the immunogenicity of vaccines for infants and to investigate whether the incidence of reactogenicity is reduced after each immunisation dose using needles of varying lengths and gauges.
  
  
  METHODS
  Randomised controlled trial.
  
  
  METHODS
  18 general practices within two UK primary care trusts.
  
  
  METHODS
  696 healthy infants vaccinated at 2, 3, and 4 months of age, with follow-up to 5 months of age.
  
  
  METHODS
  Combined diphtheria, tetanus, whole cell pertussis, and Haemophilus influenzae type b vaccine and a serogroup C meningococcal glycoconjugate vaccine administered using either a wide, long needle (23 gauge/0.6 mm diameter, 25 mm), a narrow, short needle (25 gauge/0.5 mm diameter, 16 mm), or a narrow, long needle (25 gauge, 25 mm).
  
  
  METHODS
  Local and general reactions recorded by parents for three days after each dose; and diphtheria, tetanus, and H influenzae type b antibody concentrations and functional antibody against serogroup C Neisseria meningitidis 28-42 days after the third dose.
  
  
  RESULTS
  Local reactions to diphtheria, tetanus, whole cell pertussis, H influenzae type b vaccinations decreased significantly with wide, long needles compared with narrow, short needles. At all three doses one less infant experienced local reactions at days 1, 2, or 3 for every six to eight vaccinated. Significantly fewer infants vaccinated with the long needle experienced severe local reactions. Non-inferiority of the immune response was shown using a wide, long needle rather than a narrow, short needle for serogroup C meningococcal glycoconjugate vaccine and for diphtheria but not for H influenzae type b or tetanus, although no evidence was found of a decrease. Little difference was found between needles of the same length but different gauges in local reaction or immune response.
  
  
  CONCLUSIONS
  Long (25 mm) needles for infant immunisations can significantly reduce vaccine reactogenicity at each dose while achieving comparable immunogenicity to that of short (16 mm) needles. Trial registration Current Controlled Trials ISRCTN62032215 [controlled-trials.com].
authors.affiliation: Oxford Vaccine Group, Centre for Clinical Vaccinology and Tropical Medicine, Department of Paediatrics, University of Oxford, Churchill Hospital, Oxford OX3 7LJ. linda.diggle@paediatrics.ox.ac.uk
authors.forename: Linda
authors.initials: L
authors.lastname: Diggle
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Deeks
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Pollard
mesh_terms: D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000009:adverse effects* / Q000276:immunology; D003875:Drug Eruptions / Q000209:etiology* / Q000276:immunology; D004867:Equipment Design; D018073:Haemophilus Vaccines / Q000009:adverse effects* / Q000276:immunology; D006801:Humans; D007223:Infant; D009339:Needles; D014611:Vaccination / Q000009:adverse effects / Q000295:instrumentation*; D017778:Vaccines, Combined
chemical_list: D015721:Diphtheria-Tetanus-Pertussis Vaccine; D018073:Haemophilus Vaccines; D017778:Vaccines, Combined