Pneumococcal vaccine is an immunization against Streptococcus pneumoniae, a bacterium that frequently causes meningitis and pneumonia in the elderly, and people with chronic illnesses. Pneumococcal pneumonia accounts for 10% to 25% of all pneumonias.
Review Date 7/25/2022
Updated by: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.