Influenza-Related Deaths Are Underestimated

Seasonal-influenza-related respiratory mortality rates are higher than previously thought, according to the results of a recent study.

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Previous estimates of 250,000 to 500,000 annual influenza-related deaths are now outdated. In order to update these numbers, researchers estimated country-specific influenza-associated respiratory excess mortality rates (EMR) for 33 countries using death records and influenza surveillance data. For countries without EMR data, WHO Global Health Estimate respiratory infection mortality rates were used. EMR-contributing countries represented 57% of the global population.

Overall, the estimated mean annual influenza-associated respiratory EMR ranged from 0.1 to 6.4 per 100,000 individuals younger than 65 years, 2.9 to 44.0 per 100,000 individuals between the ages of 65 and 74 years, and 17.9 to 223.5 per 100,000 individuals older than 75 years. The researchers estimated that 291,243 to 645,832 seasonal influenza-associated respiratory deaths occur annually.

“These global influenza-associated respiratory mortality estimates are higher than previously reported, suggesting that previous estimates might have underestimated disease burden. The contribution of non-respiratory causes of death to global influenza-associated mortality should be investigated.”

—Michael Potts


Luliano AD, Roguski KM, Change HH, et al. Estimates of global seasonal influenza-associated respiratory mortality: a modelling study [published online December 13, 2017]. Lancet. doi: