Use of pneumococcal vaccine in adults.

Abstract

of the Clinical Problem Streptococcus pneumoniae is a commoncauseof upper respiratory tract infection and community-acquired pneumonia (CAP). It also causes invasivepneumococcaldisease(IPD)suchasbacteremia,bacterialmeningitis, endocarditis, andosteomyelitis. In2012, therewere anestimated31 600casesofpneumococcal infectionand3300related deaths in theUnited States. The highest rates of infection are among children and adults aged 65 years or older.1 PPSV23was licensed in theUnitedStates in 1983.According to a 2013meta-analysis, this vaccine is associated with prevention of IPD, but there is no consistent evidence that it is associatedwith reduced rates of all-cause pneumonia or all-causemortality.2 The addition of a 7-valent PCV (PCV7) in 2000 to the pediatric vaccine schedule was associated with decreases in both pediatric and adult IPD.3PCV13 isanotherconjugated vaccine that contains capsular polysaccharide antigens from 13 strains of S pneumoniae (includingthe6Astrain,astrainnot included inPPSV23)conjugated to inactivated diphtheria-tetanus toxoid. The conjugated vaccine formulation is thought to elicit a more robust T cell– dependent immune response than PPSV23, which is processed through a T cell–independent pathway.4