U.S. Flu Vaccine Effectiveness (VE) Data for 2021-2022

At a glance

Everything you need to know about the flu illness, including symptoms, treatment and prevention.

Patients

Description of patients enrolled in the US Flu VE Network, 2021-2022

Total respondents: 4,312*

Age Number % Total
6 months-8 years 724 17
9-17 years 620 14
18-49 years 1,863 43
50-64 years 669 16
65 years and older 436 10

*Note: 1,932 people who were positive for the virus that causes COVID-19 (SARS-CoV-2) were excluded.

Influenza A and A(H3N2)

Vaccine effectiveness against medically attended influenza A and A(H3N2), 2021–2022

Flu type Flu-positive Flu-negative Adjusted Interim VE*
Total Vaccinated no.
(%)
Total Vaccinated no.
(%)
% Confidence Interval
Flu A
Overall 468 198 (42%) 3,844 2,265 (59%) 36 (21–48)
Flu A (H3N2)
Overall 440 182 (41%) 3,844 2,265 (59%) 36 (20–49)

Influenza A(H3N2) by Age Group

Vaccine effectiveness against medically attended influenza A(H3N2), 2021–22

Flu type Flu-positive Flu-negativeB Adjusted Interim VEC
Total Vaccinated no.
(%)
Total Vaccinated no.
(%)
% Confidence Interval
Influenza A(H3N2)
Overall 440 182 (41%) 3,844 2,265 (59%) 36 (21–48)
6 mos – 8 years 95 33 (35%) 622 356 (57%) 51 (19–70)
9 – 17 years 117 39 (33%) 499 214 (43%) 34 (-7–59)
18 – 49 years 165 68 (41%) 1,685 935 (55%) 32 (3–52)
50 years and older 63 42 (67%) 1,039 760 (73%) 10 (-60-49)
  • Price, et al, 2022
  • VE = vaccine effectiveness
  • Persons testing negative for both influenza virus and SARS-CoV-2 using molecular assays.
  • Multivariable logistic regression models adjusted for site, age, month of onset, self-rated general health status, and race/ethnicity.