Longer Needle Length Reduces Frequency and Severity of Local Vaccine Reactions

Researchers from the UK assessed the influence of needle size on vaccine immunogenicity and reactogenicity. This randomized controlled trial included 696 healthy infants from 18 general practices. Exclusion criteria included less than 37 weeks’ gestation or birth weight less than 2500 grams. Routine vaccines were given at 2, 3, and 4 months of age (according to the UK schedule, which differs from the US), with a follow-up visit at 5 months. The immunizations administered included a combined diphtheria, tetanus, whole cell pertussis, Haemophilus influenzae type b vaccine and a serogroup C meningococcal glycoconjugate vaccine. Using the technique advocated by the WHO, the vaccines were administered into the anterolateral thigh utilizing 1 of 3 needle types of varying diameter and length: a wide, long needle (23 gauge, 25 mm); a narrow, short needle (25 gauge, 16 mm); or a narrow, long needle (25 gauge, 25 mm). Of the 696 infants enrolled, 240 were randomized to the wide, long …