Absolute and Relative Vaccine Effectiveness of Primary and Booster Series of COVID-19 Vaccines (mRNA and Adenovirus Vector) Against COVID-19 Hospitalizations in the United States, December 2021–April 2022. (31st December 2022)

• Record Type: Journal Article
• Authors: Lewis, Nathaniel M; Murray, Nancy; Adams, Katherine; Surie, Diya; Gaglani, Manjusha; Ginde, Adit A; McNeal, Tresa; Ghamande, Shekhar; Douin, David J; Talbot, H Keipp; Casey, Jonathan D; Mohr, Nicholas M; Zepeski, Anne; Shapiro, Nathan I; Gibbs, Kevin W; Files, D Clark; Hager, David N; Ali, Harith; Prekker, Matthew E; Frosch, Anne E; Exline, Matthew C; Gong, Michelle N; Mohamed, Amira; Johnson, Nicholas J; Srinivasan, Vasisht; Steingrub, Jay S; Peltan, Ithan D; Brown, Samuel M; Martin, Emily T; Monto, Arnold S; Lauring, Adam S; Khan, Akram; Hough, Catherine L; Busse, Laurence W; Bender, William; Duggal, Abhijit; Wilson, Jennifer G; Gordon, Alexandra June; Qadir, Nida; Chang, Steven Y; Mallow, Christopher; Rivas, Carolina; Babcock, Hilary M; Kwon, Jennie H; Chappell, James D; Halasa, Natasha; Grijalva, Carlos G; Rice, Todd W; Stubblefield, William B; Baughman, Adrienne; Lindsell, Christopher J; Hart, Kimberly W; Rhoads, Jillian P; McMorrow, Meredith L; Tenforde, Mark W; Self, Wesley H; Patel, Manish M;
• Is Part Of: Open forum infectious diseases. Volume 10:Number 1(2023)
• Publication Date: 2022-12-31
• Subjects: absolute vaccine effectiveness -- booster vaccine series -- COVID-19 -- primary vaccine series -- relative vaccine effectiveness; Communicable diseases -- Periodicals; Medical microbiology -- Periodicals; Infection -- Periodicals; 616.9
• DOI: 10.1093/ofid/ofac698
• Languages: English
• ISSNs: 2328-8957

Abstract

Abstract: Background: Coronavirus disease 2019 (COVID-19) vaccine effectiveness (VE) studies are increasingly reporting relative VE (rVE) comparing a primary series plus booster doses with a primary series only. Interpretation of rVE differs from traditional studies measuring absolute VE (aVE) of a vaccine regimen against an unvaccinated referent group. We estimated aVE and rVE against COVID-19 hospitalization in primary-series plus first-booster recipients of COVID-19 vaccines. Methods: Booster-eligible immunocompetent adults hospitalized at 21 medical centers in the United States during December 25, 2021–April 4, 2022 were included. In a test-negative design, logistic regression with case status as the outcome and completion of primary vaccine series or primary series plus 1 booster dose as the predictors, adjusted for potential confounders, were used to estimate aVE and rVE. Results: A total of 2060 patients were analyzed, including 1104 COVID-19 cases and 956 controls. Relative VE against COVID-19 hospitalization in boosted mRNA vaccine recipients versus primary series only was 66% (95% confidence interval [CI], 55%–74%); aVE was 81% (95% CI, 75%–86%) for boosted versus 46% (95% CI, 30%–58%) for primary. For boosted Janssen vaccine recipients versus primary series, rVE was 49% (95% CI, −9% to 76%); aVE was 62% (95% CI, 33%–79%) for boosted versus 36% (95% CI, −4% to 60%) for primary. Conclusions: Vaccine booster doses increased protection against COVID-19 hospitalization compared with a primary series. Comparing rVE measures across studies can lead to flawed interpretations of the added value of a new vaccination regimen, whereas difference in aVE, when available, may be a more useful metric. Abstract : Although relative vaccine effectiveness can be a useful measure to understand incremental benefit of a vaccine booster regimen compared with a primary series alone, absolute vaccine effectiveness estimates are needed to fully understand their benefit.