Epidemiology of Invasive Pneumococcal Disease among Adult Patients in Barcelona Before and After Pediatric 7‐Valent Pneumococcal Conjugate Vaccine Introduction, 1997–2007

Abstract

Rates of IPD among adults increased in Barcelona in the late PCV7 period, coinciding with a clonal expansion of non-PCV7 serotypes. In contrast, rates of IPD caused by PCV7 serotypes decreased among people aged > or = 65 years, which suggests the development of a herd immunity.