Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2022 Mar 8;15(3):322.
doi: 10.3390/ph15030322.

COVID-19 and Seasonal Influenza Vaccination: Cross-Protection, Co-Administration, Combination Vaccines, and Hesitancy

Alexander Domnich  1 , Andrea Orsi  1   2 , Carlo-Simone Trombetta  2 , Giulia Guarona  1 , Donatella Panatto  2 , Giancarlo Icardi  1   2
Affiliations
Review

COVID-19 and Seasonal Influenza Vaccination: Cross-Protection, Co-Administration, Combination Vaccines, and Hesitancy

Alexander Domnich et al. Pharmaceuticals (Basel). .

Abstract

SARS-CoV-2 and influenza are the main respiratory viruses for which effective vaccines are currently available. Strategies in which COVID-19 and influenza vaccines are administered simultaneously or combined into a single preparation are advantageous and may increase vaccination uptake. Here, we comprehensively review the available evidence on COVID-19/influenza vaccine co-administration and combination vaccine candidates from the standpoints of safety, immunogenicity, efficacy, policy and public acceptance. While several observational studies have shown that the trained immunity induced by influenza vaccines can protect against some COVID-19-related endpoints, it is not yet understood whether co-administration or combination vaccines can exert additive effects on relevant outcomes. In randomized controlled trials, co-administration has proved safe, with a reactogenicity profile similar to that of either vaccine administered alone. From the immunogenicity standpoint, the immune response towards four influenza strains and the SARS-CoV-2 spike protein in co-administration groups is generally non-inferior to that seen in groups receiving either vaccine alone. Several public health authorities have advocated co-administration. Different combination vaccine candidates are in (pre)-clinical development. The hesitancy towards vaccine co-administration or combination vaccines is a multifaceted phenomenon and may be higher than the acceptance of either vaccine administered separately. Public health implications are discussed.

Keywords: COVID-19; combination vaccines; influenza; vaccination; vaccine co-administration.

PubMed Disclaimer

Conflict of interest statement

All authors declare no conflict of interest regarding this publication.

References

    1. Schaffer DeRoo S., Pudalov N.J., Fu L.Y. Planning for a COVID-19 Vaccination Program. JAMA. 2020;323:2458–2459. doi: 10.1001/jama.2020.8711. - DOI - PubMed
    1. World Health Organization (WHO) Vaccines against influenza WHO position paper—November 2012. Wkly. Epidemiol. Rec. 2012;87:461–476. - PubMed
    1. Paget J., Spreeuwenberg P., Charu V., Taylor R.J., Iuliano A.D., Bresee J., Simonsen L., Viboud C. Global Seasonal Influenza-associated Mortality Collaborator Network and GLaMOR Collaborating Teams. Global mortality associated with seasonal influenza epidemics: New burden estimates and predictors from the GLaMOR Project. J. Glob. Health. 2019;9:020421. doi: 10.7189/jogh.09.020421. - DOI - PMC - PubMed
    1. World Health Organization (WHO) FluNet. [(accessed on 7 February 2022)]. Available online: https://www.who.int/tools/flunet.
    1. Fast H.E., Zell E., Murthy B.P., Murthy N., Meng L., Scharf L.G., Black C.L., Shaw L., Chorba T., Harris L.Q. Booster and additional primary dose COVID-19 vaccinations among adults aged ≥65 years—United States, August 13, 2021–November 19, 2021. MMWR Morb. Mortal. Wkly. Rep. 2021;70:1735–1739. doi: 10.15585/mmwr.mm7050e2. - DOI - PMC - PubMed

LinkOut - more resources