Retail flu vaccinations in the U.S. by flu season
Flu shots—which take one to two weeks to be fully effective—were lagging through September compared with recent years.
July-August
September
October
November
December
January-February
10.9 M
11.9 M
22.9 M
12.5 M
36.8 M
50.1 M
42.7 M
2019-2020
2020-2021
2021-2022
2022-2023
