Vaccine Effectiveness Against Influenza A(H3N2)-Associated Hospitalized Illness: United States, 2022.

ABSTRACT:

Background

The COVID-19 pandemic was associated with historically low influenza circulation during the 2020-2021 season, followed by an increase in influenza circulation during the 2021-2022 US season. The 2a.2 subgroup of the influenza A(H3N2) 3C.2a1b subclade that predominated was antigenically different from the vaccine strain.

Methods

To understand the effectiveness of the 2021-2022 vaccine against hospitalized influenza illness, a multistate sentinel surveillance network enrolled adults aged ≥18 years hospitalized with acute respiratory illness and tested for influenza by a molecular assay. Using the test-negative design, vaccine effectiveness (VE) was measured by comparing the odds of current-season influenza vaccination in influenza-positive case-patients and influenz

SUBMITTER: Tenforde MW 

PROVIDER: S-EPMC10226741 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature