Public health impact of pneumococcal conjugate vaccine infant immunization programs: assessment of invasive pneumococcal disease burden and serotype distribution.

After introduction of pediatric PCV programs, the residual overall IPD burden in children was low and in a narrow range across countries with high vaccination coverage, irrespective of differences in PCV programs and pneumococcal epidemiology. Effects on overall IPD were more variable in the elderly. Whereas IPD was mainly due to VTs before PCV introduction, NVTs are the major contributor today in children and adults.