Community-acquired pneumonia: pneumococcal vaccine
Community-acquired pneumonia is an important threat to the health of older people, as well as others with high-risk conditions. Streptococcus pneumoniae, or pneumococcus, is a major cause of pneumonia.
Focus of the review
Summarising the evidence to help prevent community-acquired pneumonia is relevant clinically and for public health. Vaccination is a potentially important strategy to prevent pneumonia and, therefore, summarising the evidence in support of this intervention is worthwhile.
Comments on evidence
Evidence from clinical trials helps to inform policy as it pertains to vaccination for prevention of pneumonia.
Search and appraisal summary
The update literature search for this overview was carried out from the date of the last search, January 2010, to April 2014. For more information on the electronic databases searched and criteria applied during assessment of studies for potential relevance to the overview, please see the Methods section. Searching of electronic databases retrieved 651 studies. After deduplication and removal of conference abstracts, 403 records were screened for inclusion in the overview. Appraisal of titles and abstracts led to the exclusion of 348 studies and the further review of 55 full publications. Of the 55 full articles evaluated, eight systematic reviews and one RCT were added at this update. In addition, one RCT was added to the Comment section.
An influential RCT was published in 2015, the CAPITA trial, in adults aged 65 years and older. As this was after the search date of this overview, it has been included in the relevant Comment section. This RCT demonstrated benefit of a conjugate pneumococcal vaccine in preventing community-acquired pneumonia due to vaccine strains of pneumococcus.
Substantive changes at this update
INTRODUCTION: In the Northern Hemisphere about 12/1000 people per year (on average) contract pneumonia while living in the community, with most cases caused by Streptococcus pneumoniae. Mortality ranges from about 5% to 35% depending on severity of disease, with a worse prognosis in older people, men, and people with chronic diseases. METHODS AND OUTCOMES: We conducted a systematic overview, aiming to answer the following clinical question: What are the effects of pneumococcal vaccine to prevent community-acquired pneumonia? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2014 (BMJ Clinical Evidence overviews are updated periodically; please check our website for the most up-to-date version of this overview). RESULTS: At this update, searching of electronic databases retrieved 651 studies. After deduplication and removal of conference abstracts, 403 records were screened for inclusion in the overview. Appraisal of titles and abstracts led to the exclusion of 348 studies and the further review of 55 full publications. Of the 55 full articles evaluated, eight systematic reviews and one RCT were added at this update. In addition, one RCT was added to the Comment section. We performed a GRADE evaluation for five PICO combinations. CONCLUSIONS: In this systematic overview, we categorised the efficacy for two intervention based on information about the effectiveness and safety of conjugated vaccine and polysaccharide vaccine.