Could a Flu Shot Lower the Risk of Pneumonia?

The risk of acquiring influenza-related pneumonia is significantly less in patients who receive the seasonal flu vaccine, according to a recent study.

While pneumonia is a common and serious complication of influenza, few studies have examined the effects of the influenza vaccine on the risk of developing pneumonia.

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To further assess this relationship, researchers conducted a prospective observational multicernter study of 2767 patients hospitalized for pneumonia between 2010 and 2012.

Of the 2767 patients, 162 had lab-confirmed influenza.

Overall, 17% of those with lab-confirmed flu-associated pneumonia had been vaccinated, while 29% of patients with flu-negative pneumonia had been vaccinated. The adjusted odds ratio of prior influenza vaccination between flu-associated and flu-negative pneumonia was 0.43.

“Among children and adults hospitalized with community-acquired pneumonia, those with laboratory-confirmed influenza-associated pneumonia, compared with those with pneumonia not associated with influenza, had lower odds of having received influenza vaccination,” they concluded.

—Michael Potts


Grijalva CG, Zhu Y, Williams DJ, et al. Association between hospitalization with community-acquired laboratory-confirmed influenza pneumonia and prior receipt of influenza vaccination. JAMA. October 5, 2015 [epub ahead of print]. doi:10.1001/jama.2015.12160.