Immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine administered to older infants and children naïve to pneumococcal vaccination.

•Some children may not receive pneumococcal conjugate vaccine (PCV) as infants.•PCV13 was evaluated in pneumococcal vaccine-naïve children aged 7 months to 5 years.•Age-specific “catch-up” vaccination schedules were evaluated.•The proportion of immunological responders ranged from 88% to 100% for all 13 serotypes.•PCV13 was generally well-tolerated; trend for greater tenderness in older subjects.