High-Dose Influenza Vaccine Is Associated With Reduced Mortality Among Older Adults With Breakthrough Influenza Even When There Is Poor Vaccine-Strain Match

© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America..

BACKGROUND: High-dose (HD) influenza vaccine offers improved protection from influenza virus infection among older adults compared with standard-dose (SD) vaccine. Here, we explored whether HD vaccine attenuates disease severity among older adults with breakthrough influenza.

METHODS: This was a retrospective cohort study of US claims data for influenza seasons 2016-2017, 2017-2018, and 2018-2019, defined as 1 October through 30 April, among adults aged ≥65 years. After adjusting the different cohorts for the probability of vaccination conditional on patients' characteristics, we compared 30-day mortality rate post-influenza among older adults who experienced breakthrough infection after receipt of HD or SD influenza vaccines and among those not vaccinated (NV).

RESULTS: We evaluated 44 456 influenza cases: 23 109 (52%) were unvaccinated, 15 037 (33.8%) received HD vaccine, and 6310 (14.2%) received SD vaccine. Significant reductions in mortality rates among breakthrough cases were observed across all 3 seasons for HD vs NV, ranging from 17% to 29% reductions. A significant mortality reduction of 25% was associated with SD vaccination vs NV in the 2016-2017 season when there was a good match between circulating influenza viruses and selected vaccine strains. When comparing HD vs SD cohorts, mortality reductions were higher among those who received HD in the last 2 seasons when mismatch between vaccine strains and circulating H3N2 viruses was documented, albeit not significant.

CONCLUSIONS: HD vaccination was associated with lower post-influenza mortality among older adults with breakthrough influenza, even during seasons when antigenically drifted H3N2 circulated. Improved understanding of the impact of different vaccines on attenuating disease severity is warranted when assessing vaccine policy recommendations.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:77

Enthalten in:

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America - 77(2023), 7 vom: 05. Okt., Seite 1032-1042

Sprache:

Englisch

Beteiligte Personen:

Chaves, Sandra S [VerfasserIn]
Naeger, Sarah [VerfasserIn]
Lounaci, Kahina [VerfasserIn]
Zuo, Yue [VerfasserIn]
Loiacono, Matthew M [VerfasserIn]
Pilard, Quentin [VerfasserIn]
Nealon, Joshua [VerfasserIn]
Genin, Marie [VerfasserIn]
Mahe, Cedric [VerfasserIn]

Links:

Volltext

Themen:

Breakthrough influenza
Disease attenuation
High-dose influenza vaccine
Influenza
Influenza Vaccines
Journal Article
Research Support, Non-U.S. Gov't
Severe influenza

Anmerkungen:

Date Completed 23.10.2023

Date Revised 06.11.2023

published: Print

Citation Status MEDLINE

doi:

10.1093/cid/ciad322

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM35749508X