Pneumococcal vaccine in the elderly: a useful but forgotten vaccine.

Pneumococcal disease in the elderly is a major concern emphasizing the need for prevention. The review focuses on a literature-based analysis of the efficacy ("does the vaccine works?") and/or the effectiveness ("does vaccination help older population?") of pneumococcal vaccines 14- or 23-valent (PPV23) in the elderly. In the setting of Streptococcus pneumoniae pneumonia, there is still no conclusive evidence decisively confirming the efficacy of pneumococcal vaccine against pneumococcal pneumonia in the elderly populations. However, the efficacy of pneumococcal vaccination has been demonstrated in the prevention of invasive pneumococcal disease (IPD) such as bacteremia, which is the main complication of pneumonia. In the setting of IPD in the elderly, analysis of the current literature provides evidence for both the efficacy and effectiveness of PPV23, but most of the clinical studies failed to demonstrate a substantial reduction in all-cause mortality rate. The community-acquired pneumonia guidelines in the industrialized countries include recommendations for pneumococcal vaccine by PPV23 for adults aged 65 years and over. Taking into account the preventive effect of PPV23 on IPD and the threat of a pandemic flu, the increase of PPV23 vaccination coverage in elderly patients should be strongly considered.