Corresponding Author: Mark W. Tenforde, MD, PhD, Centers for Disease Control and Prevention, 1600 Clifton Rd, Mailstop 24/7, Atlanta, GA 30329 (mtenforde@cdc.gov).
Accepted for Publication: October 13, 2021.
Published Online: November 4, 2021. doi:10.1001/jama.2021.19499
Author Contributions: Dr Tenforde had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Drs Tenforde and Self and Ms Adams contributed equally to this work as lead authors.
Concept and design: Tenforde, Self, Adams, Ginde, Talbot, Hager, Exline, Gong, Peltan, Brown, Busse, Qadir, Grijalva, Rice, Kobayashi, Verani, Patel.
Acquisition, analysis, or interpretation of data: Tenforde, Self, Adams, Gaglani, Ginde, McNeal, Ghamande, Douin, Talbot, Casey, Mohr, Zepeski, Shapiro, Gibbs, Files, Hager, Shehu, Prekker, Erickson, Exline, Gong, Mohamed, Henning, Steingrub, Peltan, Brown, Martin, Monto, Khan, Hough, Busse, ten Lohuis, Duggal, Wilson, Gordon, Qadir, Chang, Mallow, Rivas, Babcock, Kwon, Halasa, Chappell, Lauring, Grijalva, Rice, Jones, Stubblefield, Baughman, Womack, Rhoads, Lindsell, Hart, Zhu, Olson, Patel.
Drafting of the manuscript: Tenforde, Self, Adams, Mohamed, Khan, Mallow, Patel.
Critical revision of the manuscript for important intellectual content: Tenforde, Self, Adams, Gaglani, Ginde, McNeal, Ghamande, Douin, Talbot, Casey, Mohr, Zepeski, Shapiro, Gibbs, Files, Hager, Shehu, Prekker, Erickson, Exline, Gong, Henning, Steingrub, Peltan, Brown, Martin, Monto, Khan, Hough, Busse, ten Lohuis, Duggal, Wilson, Gordon, Qadir, Chang, Mallow, Rivas, Babcock, Kwon, Halasa, Chappell, Lauring, Grijalva, Rice, Jones, Stubblefield, Baughman, Womack, Rhoads, Lindsell, Hart, Zhu, Olson, Kobayashi, Verani, Patel.
Statistical analysis: Tenforde, Adams, Talbot, Casey, Monto, Grijalva, Lindsell, Zhu, Olson.
Obtained funding: Self, Steingrub, Verani, Patel.
Administrative, technical, or material support: Self, Mohr, Files, Hager, Exline, Gong, Khan, ten Lohuis, Duggal, Wilson, Gordon, Qadir, Mallow, Babcock, Jones, Baughman, Womack, Rhoads, Lindsell, Hart, Kobayashi, Verani, Patel.
Supervision: Self, Mohr, Shapiro, Exline, Henning, Martin, Monto, Khan, ten Lohuis, Wilson, Gordon, Halasa, Chappell, Grijalva, Hart, Patel.
Operational support for enrollment: McNeal.
Data cleaning, data management: Olson.
Supervision of staff at study site: Kwon.
Conflict of Interest Disclosures: Dr Self reported receiving grants from the Centers for Disease Control and Prevention (CDC) (principal investigator of the primary funding contract from CDC for this work) during the conduct of the study. Dr Gaglani reported receiving grants from CDC, Vanderbilt University Medical Center, Baylor Scott & White Health (BSWH), and the IVY study during the conduct of the study; grants from CDC–BSWH HAIVEN influenza/COVID-19 vaccine effectiveness study, CDC–BSWH ambulatory US influenza/COVID-19 vaccine effectiveness study, CDC–Abt Associates BSWH RECOVER COVID-19/influenza study, and CDC–Westat BSWH VISION COVID-19/influenza study outside the submitted work; and Pfizer BSWH Independent Grants for Learning & Change for meningococcal vaccination of adolescents and an institutional contract with Janssen (BSWH Observational RSV Study in infants). Dr Ginde reported receiving grants from CDC during the conduct of the study; and grants from the National Institutes of Health (NIH), Department of Defense, and AbbVie outside the submitted work. Dr McNeal reported receiving grants from the CDC HAIVEN study group that become the IVY-3 study group during the conduct of the study. Dr Talbot reported receiving grants from CDC during the conduct of the study. Dr Casey reported receiving grants from NIH K23HL153584 outside the submitted work. Dr Mohr reported receiving grants from CDC during the conduct of the study. Dr Shapiro reported receiving grants from CDC during the conduct of the study. Dr Files reported receiving grants from CDC during the conduct of the study and personal fees from Cytovale and Medpace outside the submitted work. Dr Prekker reported receiving grants from CDC during the conduct of the study. Dr Exline reported receiving a speaking honorarium from Abbott Laboratories outside the submitted work. Dr Gong reported receiving grants from CDC during the conduct of the study; grants from NIH to conduct clinical trials on COVID-19 and non–COVID-19 outside the submitted work; and data and safety monitoring board fees for participating in Regeneron trials outside the submitted work. Dr Henning reported receiving grants from CDC during the conduct of the study. Dr Peltan reported receiving grants from CDC during the conduct of the study; grants from NIH, Intermountain Research and Medical Foundation, and Janssen Pharmaceuticals outside the submitted work; and payment to Intermountain Medical Center for subject enrollment from Regeneron and Asahi Kasei Pharma outside the submitted work. Dr Brown reported receiving grants from CDC during the conduct of the study. Dr Martin reported receiving grants from CDC during the conduct of the study and personal fees from Pfizer outside the submitted work. Dr Khan reported receiving grants from United Therapeutics, Actelion Pharmaceuticals, Eli Lilly, Johnson & Johnson, Regeneron Pharmaceuticals, and Gilead Sciences outside the submitted work. Dr Hough reported receiving grants from CDC during the conduct of the study and grants from NIH outside the submitted work. Dr Wilson reported receiving grants from CDC/Vanderbilt during the conduct of the study. Dr Chang reported receiving personal fees from La Jolla Pharmaceuticals and PureTech Health outside the submitted work. Dr Babcock reported receiving grants from CDC during the conduct of the study. Dr Kwon reported receiving grants from NIH National Institute of Allergy and Infectious Diseases (award 1K23 AI137321-01A1) outside the submitted work. Dr Halasa reported receiving grants from CDC during the conduct of the study; grants from Sanofi outside the submitted work; and hemagglutination inhibition and microneutralization testing, vaccine donation, and grants from Quidel outside the submitted work. Dr Chappell reported receiving grants from CDC during the conduct of the study. Dr Lauring reported receiving consulting fees from Sanofi for an influenza antiviral and fees from Roche as a member of an influenza antiviral trial steering committee outside the submitted work. Dr Grijalva reported receiving a contract from CDC during the conduct of the study; consulting fees from Pfizer, Merck, and Sanofi; a contract from CDC, Campbell Alliance, and the Food and Drug Administration outside the submitted work; and grants from NIH and the Agency for Healthcare Research and Quality outside the submitted work. Dr Rice reported receiving grants from CDC during the conduct of the study and personal fees from Cumberland Pharmaceuticals, Sanofi, and Cytovale outside the submitted work. Dr Lindsell reported receiving grants from CDC to Vanderbilt University during the conduct of the study; grants from NIH to institution, grants from Department of Defense to institution, contracts to Vanderbilt University for research services from bioMérieux, Endpoint Health, and Entegrion. In addition, he had a patent for risk stratification in sepsis and septic shock, issued to Cincinnati Children's Hospital Medical Center. Dr Zhu reported receiving grants from CDC during the conduct of the study. No other disclosures were reported.
Funding/Support: Primary funding for this study was provided by the CDC (75D30121F00002).
Role of the Funder/Sponsor: Investigators from CDC were involved in all aspects of the study, including the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. The CDC had the right to control decisions about publication via the CDC publication clearance process.
Group Information: A full list of investigators and collaborators in the Influenza and Other Viruses in the Acutely Ill (IVY) Network is available in eAppendix 1 in the Supplement.
Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the CDC.
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