How many global influenza cases result in death each year?

Global Influenza Mortality Estimates

Seasonal influenza causes approximately 290,000 to 650,000 respiratory deaths globally each year, with the most recent high-quality modeling studies converging on this range. 1, 2

Annual Global Death Burden

The best available evidence from large-scale modeling studies provides the following estimates:

• 389,000 respiratory deaths annually (uncertainty range: 294,000-518,000) based on data from 31 countries representing 57% of the global population during 2002-2011 1

• 291,000 to 645,000 seasonal influenza-associated respiratory deaths (4.0-8.8 per 100,000 individuals) occur annually based on country-specific excess mortality data from 33 countries during 1999-2015 2

• These contemporary estimates are substantially higher than the outdated WHO estimate of 250,000-500,000 deaths that was previously cited 1, 2

Age Distribution of Deaths

More than 90% of influenza deaths occur in adults aged ≥65 years, making this the highest-risk population for mortality 3

• 67% of all respiratory deaths from influenza occur in people aged 65 years and older 1

• During 1990-1999 in the United States, estimated average rates of influenza-associated pulmonary and circulatory deaths per 100,000 persons were:

  • 0.4-0.6 among persons aged 0-49 years 3
  • 7.5 among persons aged 50-64 years 3
  • 98.3 among persons aged ≥65 years 3

Geographic Variation

Mortality rates vary substantially by region, with the highest burden in resource-limited settings:

• Sub-Saharan Africa: 2.8-16.5 deaths per 100,000 individuals 2
• Southeast Asia: 3.5-9.2 deaths per 100,000 individuals 2
• These regions experience higher mortality due to lower baseline health care access and higher respiratory infection mortality rates 1

Pediatric Mortality

Among children younger than 5 years, an estimated 9,000-106,000 influenza-associated respiratory deaths occur annually in 92 countries with high respiratory infection mortality rates 2

United States-Specific Data

In the United States alone, seasonal influenza causes substantial mortality:

• 17,000 to 51,000 deaths per epidemic during the 1990-91 through 1998-99 seasons (mean: 36,000 deaths) 3

• During severe epidemic years, more than 40,000 influenza-associated deaths were estimated in 6 of 11 epidemics between 1972-1995 3

• More than 35,000 deaths and 200,000 hospitalizations occur annually in the United States 4

Important Caveats

The variation in mortality estimates reflects several factors:

• Influenza A(H3N2) seasons cause higher mortality than H1N1 seasons, with H3N2 predominating in 90% of seasons during 1990-1999 compared to 57% during 1976-1990 3

• Non-respiratory causes of death (cardiac complications, exacerbations of chronic diseases) are not fully captured in respiratory-focused estimates, suggesting the true burden may be even higher 2

• Lower baseline respiratory mortality and better health care access are associated with lower influenza mortality in persons <65 years, indicating that health care improvements in low- and middle-income countries could substantially reduce the global burden 1