Past Seasons Estimated Influenza Disease Burden Averted by Vaccination

This web page provides estimates on the burden of seasonal influenza and of the impact of annual influenza vaccination in the United States for the 2014–2015 through the 2021-2022 influenza seasons.

Table 1: Estimated Number of Influenza Illnesses, Medical Visits, Hospitalizations, and Deaths Averted by Vaccination, by Age Group, 2010-11 through 2021-22 Influenza Seasons
Averted Symptomatic Illnesses Averted Medical Visits Averted Hospitalizations Averted Deaths
Season Estimate 95% UI Estimate 95% UI Estimate 95% UI Estimate 95% UI
2010-2011 5,600,000 (3,100,000, 14,000,000) 2,800,000 (1,700,000, 6,900,000) 80,000 (19,000, 380,000) 9,800 (1,300, 58,000)
2011-2012 2,200,000 (830,000, 12,000,000) 1,100,000 (410,000, 5,400,000) 44,000 (4,900, 320,000) 4,200 (320, 41,000)
2012-2013 5,500,000 (3,700,000, 11,000,000) 2,700,000 (1,900,000, 5,300,000) 60,000 (23,000, 290,000) 3,700 (850, 25,000)
2013-2014 7,500,000 (4,300,000, 12,000,000) 3,500,000 (2,000,000, 5,500,000) 100,000 (35,000, 250,000) 12,000 (2,300, 41,000)
2014-2015 1,400,000 (8,300, 4,200,000) 700,000 (4,200, 2,100,000) 39,000 (160, 190,000) 3,700 (13, 20,000)
2015-2016 5,300,000 (2,500,000, 9,200,000) 2,700,000 (1,300,000, 4,500,000) 70,000 (15,000, 170,000) 5,900 (510, 20,000)
2016-2017 5,300,000 (2,400,000, 11,000,000) 2,700,000 (1,300,000, 5,400,000) 72,000 (13,000, 190,000) 5,200 (360, 16,000)
2017-2018 5,900,000 (4,700,000, 7,400,000) 3,100,000 (2,400,000, 3,900,000) 82,000 (40,000, 100,000) 4,800 (1,000, 14,000)
2018-2019 3,100,000 (2,400,000, 4,700,000) 1,600,000 (1,200,000, 2,400,000)) 43,000 (30,000, 160,000) 2,800 (700, 16,000))
2019-2020 7,000,000 (5,400,000, 8,900,000) 3,400,000 (2,600,000, 4,300,000) 100,000 (52,000, 153,000) 7,100 (2,000, 27,000)
2021-2022 1,800,000 (1,000,000, 2,800,000) 1,000,000 (500,000, 1,400,000) 22,000 (6,000, 60,000) 1,000 (0, 7,000)

*Estimates are not available for the 2020-2021 flu season due to minimal influenza activity.