Invasive Pneumococcal Disease in UK Children <1 Year of Age in the Post–13-Valent Pneumococcal Conjugate Vaccine Era: What Are the Risks Now?

Abstract Background Invasive pneumococcal disease (IPD) has declined significantly since the introduction of pneumococcal conjugate vaccines (PCVs). It is not known whether certain infant populations remain at higher risk of IPD in countries with established 13-valent PCV (PCV13) programs. We aimed to describe the epidemiology, clinical characteristics, serotype distribution, and outcomes of IPD in infants, and to estimate the relative risk of PCV13-type, non-PCV13-type, and overall IPD in premature infants compared to term infants during a 4-year period after the PCV13 program was established. Methods This was a prospective, enhanced national surveillance of laboratory-confirmed IPD in England in infants aged