Immunogenicity up to age 5 years following a single-dose or two-dose infant primary series of 10-valent or 13-valent pneumococcal conjugate vaccine each followed by a booster dose in South Africa: extended follow-up of a single-centre, open-label, non-inferiority, randomised controlled trial.
BACKGROUND Reduced-dosing pneumococcal conjugate vaccine (PCV) schedules (single primary dose plus booster [1+1]) are being considered and have been deployed in the UK. We aimed to evaluate the persistence of serotype-specific immunity until age 5 years in infants randomly assigned to 1+1 or two primary doses plus boos...