Vaccination Does Not Prevent Pneumonia In Older People
New England Journal of Medicine (NEJM)
By Anne MacLennan
Pneumococcal polysaccharide vaccination helps to
guard older people against life-threatening bacteraemia but offers them
little if any protection against pneumonia.
This finding was reporting following a retrospective study of 47,000
people aged 65 years or more.
Streptococcus pneumoniae is the chief cause of pneumonia in older
adults. Until now, it has been unclear whether the pneumococcal vaccine
alters the overall risk of the acquiring the disease in the community.
Dr Lisa A. Jackson from the Center for Health Studies, Group Health
Cooperative, and the University of Washington, Seattle, United States,
led this 3-year follow-up investigation of the effectiveness of the
Primary outcomes were hospitalisation because of community- acquired
pneumonia, pneumonia in patients who were not hospitalised ("outpatient
pneumonia") and pneumococcal bacteraemia.
Over the 3-year study period, 1,428 of the total of 47,365 participants
were hospitalised with community- acquired pneumonia. Of these, 3,061
were diagnosed with outpatient pneumonia and 61 with pneumococcal
Investigators evaluated the link between pneumococcal vaccination and
risk of each outcome via multivariate Cox proportional-hazards models,
taking into account a range of factors. These included age, sex,
nursing-home residence or non-residence, smoking status, medical
conditions and receipt or non-receipt of influenza vaccine.
The pneumococcal vaccination was linked with a significant reduction in
risk of pneumococcal bacteraemia. However, over the 3 years of
follow-up, there was no reduction in risk of community-acquired
Thus, the findings support the effectiveness of the pneumococcal
polysaccharide vaccine for preventing bacteraemia. However, they also
point to the need for strategies to prevent non-bacteraemic pneumonia, a
more common manifestation of pneumococcal infection in older people, the
Other contributors to this study were from the Veterans Affairs Puget
Sound Health Care System, also in Seattle, and the Centers for Disease
Control and Prevention, Atlanta, Georgia.
N Engl J Med 2003;348:1747-1755.