Efficacy of 23-valent pneumococcal polysaccharide vaccine in preventing community-acquired pneumonia among immunocompetent adults: A systematic review and meta-analysis of randomized trials.

Data on the efficacy of the 23-valent pneumococcal polysaccharide vaccine (PPV-23) in preventing adult community-acquired pneumonia (CAP) among the target population of individuals aged over 65 years and high-risk individuals aged 19-64 years are conflicting. As the Advisory Committee on Immunization Practices (ACIP) has recently demonstrated PPV-23 is likely beneficial to immunocompromised adults by the Grading, Assessment, Development, and Evaluation (GRADE) framework, we conducted meta-analysis to examine its efficacy in an immunocompetent population.