Affiliation between Covid-19 Vaccination and Influenza Vaccination Charges


To the Editor:

The polarizing nature of vaccination towards coronavirus illness 2019 (Covid-19) inside america threatens public well being and has contributed to variable statewide vaccine uptake that ranged from 50 to 80% as of January 2022.1 Given the divided nationwide panorama and anecdotal proof from our personal sufferers, we hypothesized that low Covid-19 vaccination charges can be related to decreases in influenza vaccination charges.

Utilizing nationally consultant information from the Facilities for Illness Management and Prevention,2 we calculated modifications in influenza vaccine uptake on the state-population stage through the pandemic after Covid-19 vaccines turned extensively out there (September 2021 by January 2022) relative to earlier than the pandemic (September 2019 by January 2020). To account for pandemic-related components unrelated to Covid-19 vaccines which may have an effect on modifications in influenza vaccine uptake (e.g., worsening inequities in entry to care3,4 or employment), we additionally in contrast September 2020 by January 2021 (the primary influenza season through the pandemic however earlier than widespread Covid-19 vaccine availability) to earlier than the pandemic. We stratified modifications in influenza vaccine uptake in keeping with quartile of state-level cumulative Covid-19 vaccine uptake by January 2022. We used mixed-effects linear regressions (difference-in-differences analyses) to look at whether or not modifications in influenza vaccine uptake throughout influenza seasons earlier than as in contrast with through the pandemic differed between states with excessive as in contrast with low Covid-19 vaccine uptake. Particulars and sensitivity analyses are supplied within the Supplementary Appendix, out there with the complete textual content of this letter at

Tendencies in Influenza Vaccine Uptake Aggregated In response to Quartile of Statewide Covid-19 Vaccine Uptake amongst All Adults, All Kids, and Older Adults.

Every influenza season spans September of the indicated 12 months by January of the next 12 months (e.g., the 2021 influenza season was September 2021 by January 2022). An evidence of the lower in influenza vaccine uptake through the 2017–2018 season, along with additional interpretation of outcomes, is on the market within the Dialogue part within the Supplementary Appendix. Covid-19 denotes coronavirus illness 2019.

Influenza vaccine uptake remained comparatively steady through the first influenza season of the pandemic (Determine 1). In distinction, after Covid-19 vaccines turned extensively out there (2021–2022 season), grownup influenza vaccine uptake decreased inside states within the backside two quartiles of Covid-19 vaccine uptake (quartile 1, from 43.7% [95% confidence interval {CI}, 41.8 to 45.6] to 39.2% [95% CI, 37.0 to 41.5]; quartile 2, from 45.5% [95% CI, 42.8 to 48.2] to 43.5% [95% CI, 40.4 to 46.7]) and elevated inside states within the high two quartiles (quartile 3, from 46.9% [95% CI, 45.1 to 48.8] to 47.7% [95% CI, 45.1 to 50.4]; quartile 4, from 49.0% [95% CI, 46.7 to 51.4] to 52.8% [95% CI, 50.2 to 55.3]) (Desk S1 within the Supplementary Appendix). Variations between every quartile within the 2021–2022 season as in contrast with the 2019–2020 season are proven in Desk S2. The sensitivity evaluation evaluating the 2020–2021 season with the 2019–2020 season confirmed that influenza vaccine uptake was steady earlier than widespread Covid-19 vaccine availability, which means that different pandemic-related results corresponding to modifications in entry to care have been unlikely to have affected influenza vaccine uptake. In the course of the 2020–2021 and 2021–2022 influenza seasons, influenza vaccine uptake decreased uniformly amongst youngsters however remained steady amongst older adults, no matter Covid-19 vaccine uptake.

Though inferences about particular insurance policies and messaging selling Covid-19 vaccination are past the scope of this ecologic examine, our findings recommend that after the widespread availability of Covid-19 vaccines, components related to Covid-19 vaccination charges (e.g., security considerations and distrust of Covid-19 vaccines or authorities5) could have spilled over to have an effect on influenza vaccination charges.

Richard Ok. Leuchter, M.D.
Nicholas J. Jackson, Ph.D., M.P.H.
John N. Mafi, M.D., M.P.H.
Catherine A. Sarkisian, M.D., M.S.H.S.
David Geffen College of Medication at UCLA, Los Angeles, CA
[email protected]

Supported by grants from the Nationwide Institutes of Well being (NIH), Nationwide Coronary heart, Lung, and Blood Institute, Stimulating Entry to Analysis in Residency program at UCLA (5R38HL143614-03, to Dr. Leuchter); the NIH, Nationwide Middle for Advancing Translational Sciences UCLA Scientific and Translational Science Institute (UL1TR001881, to Dr. Sarkisian); the NIH, Nationwide Institute on Growing old (1K76AG064392-01A1, to Dr. Mafi); and the NIH, Nationwide Institute on Growing old Midcareer Award in Affected person-Oriented Growing old Analysis (2K24AG047899-06, to Dr. Sarkisian). Dr. Sarkisian was additionally supported with sources and the usage of services on the Veterans Affairs Higher Los Angeles Healthcare Middle.

Disclosure kinds supplied by the authors can be found with the complete textual content of this letter at

This letter was printed on June 15, 2022, at

  1. 1. Facilities for Illness Management and Prevention. COVID-19 vaccinations in america, county. 2022 (

  2. 2. Facilities for Illness Management and Prevention. FluVaxView: influenza (flu). 2021 (

  3. 3. Leuchter RK, Villaflores CWA, Norris KC, Sorensen A, Vangala S, Sarkisian CA. Racial disparities in probably avoidable hospitalizations through the COVID-19 pandemic. Am J Prev Med 2021;61:235239.

  4. 4. Mafi JN, Craff M, Vangala S, et al. Tendencies in US ambulatory care patterns through the COVID-19 pandemic, 2019–2021. JAMA 2022;327:237247.

  5. 5. Khairat S, Zou B, Adler-Milstein J. Elements and causes related to low COVID-19 vaccine uptake amongst extremely hesitant communities within the US. Am J Infect Management 2022;50:262267.


Supply hyperlink

Be the first to comment

Leave a Reply

Your email address will not be published.