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Cited by 633SARS-CoV-2 and COVID-19 ResearchCOVID-19 Clinical Research StudiesVaccine Coverage and Hesitancy

Association Between mRNA Vaccination and COVID-19 Hospitalization and Disease Severity

Open access
Tenforde, Mark W., Self, Wesley H., Adams, Katherine, Gaglani, Manjusha, Ginde, Adit A., McNeal, Tresa, Ghamande, Shekhar, Douin, David J. +51 more·2021·JAMA
DOI 10.1001/jama.2021.19499PMC PMC8569602
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Abstract

Importance: A comprehensive understanding of the benefits of COVID-19 vaccination requires consideration of disease attenuation, determined as whether people who develop COVID-19 despite vaccination have lower disease severity than unvaccinated people. Objective: To evaluate the association between vaccination with mRNA COVID-19 vaccines-mRNA-1273 (Moderna) and BNT162b2 (Pfizer-BioNTech)-and COVID-19 hospitalization, and, among patients hospitalized with COVID-19, the association with progression to critical disease. Design, Setting, and Participants: A US 21-site case-control analysis of 4513 adults hospitalized between March 11 and August 15, 2021, with 28-day outcome data on death and mechanical ventilation available for patients enrolled through July 14, 2021. Date of final follow-up was August 8, 2021. Exposures: COVID-19 vaccination. Main Outcomes and Measures: Associations were evaluated between prior vaccination and (1) hospitalization for COVID-19, in which case patients were those hospitalized for COVID-19 and control patients were those hospitalized for an alternative diagnosis; and (2) disease progression among patients hospitalized for COVID-19, in which cases and controls were COVID-19 patients with and without progression to death or mechanical ventilation, respectively. Associations were measured with multivariable logistic regression. Results: Among 4513 patients (median age, 59 years [IQR, 45-69]; 2202 [48.8%] women; 23.0% non-Hispanic Black individuals, 15.9% Hispanic individuals, and 20.1% with an immunocompromising condition), 1983 were case patients with COVID-19 and 2530 were controls without COVID-19. Unvaccinated patients accounted for 84.2% (1669/1983) of COVID-19 hospitalizations. Hospitalization for COVID-19 was significantly associated with decreased likelihood of vaccination (cases, 15.8%; controls, 54.8%; adjusted OR, 0.15; 95% CI, 0.13-0.18), including for sequenced SARS-CoV-2 Alpha (8.7% vs 51.7%; aOR, 0.10; 95% CI, 0.06-0.16) and Delta variants (21.9% vs 61.8%; aOR, 0.14; 95% CI, 0.10-0.21). This association was stronger for immunocompetent patients (11.2% vs 53.5%; aOR, 0.10; 95% CI, 0.09-0.13) than immunocompromised patients (40.1% vs 58.8%; aOR, 0.49; 95% CI, 0.35-0.69) (P < .001) and weaker at more than 120 days since vaccination with BNT162b2 (5.8% vs 11.5%; aOR, 0.36; 95% CI, 0.27-0.49) than with mRNA-1273 (1.9% vs 8.3%; aOR, 0.15; 95% CI, 0.09-0.23) (P < .001). Among 1197 patients hospitalized with COVID-19, death or invasive mechanical ventilation by day 28 was associated with decreased likelihood of vaccination (12.0% vs 24.7%; aOR, 0.33; 95% CI, 0.19-0.58). Conclusions and Relevance: Vaccination with an mRNA COVID-19 vaccine was significantly less likely among patients with COVID-19 hospitalization and disease progression to death or mechanical ventilation. These findings are consistent with risk reduction among vaccine breakthrough infections compared with absence of vaccination.

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Crossref · 10.1001/jama.2021.19499

Cites

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Nothing to recompute.

Claims the paper makes

0 of 16 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Vaccine breakthrough cases less often received ICU-level care than unvaccinated cases (24.6% vs 40.1%; absolute difference, -15.5%; 95% CI, -23.1% to -7.8%; P<.001).

    “Compared with unvaccinated cases, vaccine breakthrough cases less commonly received ICU-level care (24.6% vs 40.1%; absolute difference, -15.5%; 95% CI, -23.1% to -7.8%; P < .001)”
    Quote in the paperSubstantial claim
  • Findingown data

    Vaccine breakthrough cases less often received invasive mechanical ventilation than unvaccinated cases (7.7% vs 23.0%; absolute difference, -15.3%; 95% CI, -20.4% to -10.2%; P<.001).

    “and invasive mechanical ventilation (7.7% vs 23.0%; absolute difference, -15.3%; 95% CI, -20.4% to -10.2%; P < .001)”
    Quote in the paperSubstantial claim
  • Findingown data

    Unvaccinated patients made up 93.9% of those whose COVID-19 progressed to death or invasive mechanical ventilation.

    “Unvaccinated patients accounted for 93.9% (261/278) of cases with disease progression to death or invasive mechani-cal ventilation.”
    Quote in the paperSubstantial claim
  • Findingown data

    Hospitalization for COVID-19 was linked to a lower odds of being fully vaccinated with an mRNA vaccine, with 15.8% of cases versus 54.8% of controls vaccinated and an adjusted odds ratio of 0.15 (95% CI, 0.13-0.18).

    “Hospitalization for COVID-19 was significantly associated with decreased likelihood of vaccination (cases, 15.8%; controls, 54.8%; adjusted OR, 0.15; 95% CI, 0.13-0.18)”
    • Also stated in: § Association Between COVID-19 Hospitalizations and mRNA Vaccination · boosted
      “Overall, COVID-19 hospitalization was strongly associated with a lower likelihood of vaccination, with an aOR of 0.15 (95% CI, 0.13-0.18)(Figure 2).”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The multivariable models removed confounding well enough for the reported vaccination–hospitalization and vaccination–progression associations to be valid.
  • Findingown data

    Receipt of at least one COVID-19-related therapeutic during hospitalization was associated with lower odds of vaccination, adjusted odds ratio 0.32 (95% CI, 0.20-0.52).

    “Receipt of 1 or more COVID-19-related therapeutics during hospitalization was also associated with a lower likelihood of vaccination (aOR, 0.32; 95% CI, 0.20-0.52)(eTable 7 in the Supplement).”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The multivariable models removed confounding well enough for the reported vaccination–hospitalization and vaccination–progression associations to be valid.
  • May combine two claims. 12
  • The quote only partly states this claim. 1
  • Classified as probably not a substantial claim. 9

  • May combine two claims.

    Findingown data

    The analytic sample comprised 4513 hospitalized adults, of whom 1983 were COVID-19 cases and 2530 were controls without COVID-19.

    “The analytic population included 4513 patients (median age, 59 years [IQR, 45-69]; 2202 [48.8%] women; 23.0% non-Hispanic Black individuals, 15.9% Hispanic individuals, and 20.1% with an immunocompromising condition), including 1983 cases with COVID-19 and 2530 controls without it (1359 test-negative controls and 1171 syndrome-negative controls).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Vaccine breakthrough cases were older and had more chronic medical conditions than unvaccinated cases.

    “Compared with unvaccinated cases, vaccine breakthrough cases were older and had more chronic medical conditions (Table).”
    Quote in the paperNot a substantial claim

  • The quote only partly states this claim.

    Findingown data

    The association between mRNA vaccination and reduced risk of COVID-19 hospitalization was substantially weaker in immunocompromised patients than in immunocompetent patients.

    “population than the immunocompetent one, supporting recent recommendations for additional vaccine doses among immunocompromised persons.33”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Death occurred in 6.3% of vaccine breakthrough cases and 8.6% of unvaccinated patients with COVID-19.

    “Death occurred in 9 of 142 (6.3%) vaccine breakthrough cases and 91 of 1055 (8.6%) unvaccinated patients with COVID-19.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    During Delta variant circulation, the association between mRNA vaccination and reduced risk for COVID-19 hospitalization was high for illness onset within 120 days of vaccination and lower for illness onset after that period.

    “The association between mRNA vaccination and reduced risk for COVID-19 hospitalization observed during the Delta variant circulation was high for participants with illness onset within 120 days of vaccination and lower for participants with illness onset after that period.”
    • Also stated in: § Discussion · plain
      “July-August 2021 overall (Delta period) -39.5 (-43.9 to -35.1) 0.16 (0.13 to 0.21) 64/730 (8.8) 285/584 (48.8) 14-120 Days since vaccination -40.0 (-44.6 to -35.5) 0.10 (0.07 to 0.14) 127/793 (16.0) 198/497 (39.8) >120 Days since vaccination -23.8 (-28.8 to -18.8) 0.27 (0.20 to 0.37)”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductreasoning

    Because multiple comparisons could inflate type I error, secondary end point analyses should be considered exploratory.

    “Because of the potential for type I error owing to multiple comparisons, findings for analyses of secondary end points should be interpreted as exploratory.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

    Interpretationnone given

    Differences in the population vaccinated with mRNA-1273 and BNT162b2 could also contribute to observed differences in vaccine breakthrough.

    “However, differences in the population vaccinated with the mRNA-1273 and BNT162b2 vaccines could also contribute to observed differences in vaccine breakthrough.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Premisecitation

    The adjusted odds ratio was used to estimate vaccine effectiveness for preventing COVID-19 hospitalization with the formula VE = (1 - aOR) × 100%.

    “The aOR was used to estimate vaccine effectiveness for the prevention of COVID-19 hospitalizations via the following equation: vaccine effectiveness = (1 -aOR) × 100%.4,26”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [4]

      Not checked in the free run.

    • cites [26] source

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    The product-specific differences may be related to higher antigen content in mRNA-1273, a longer recommended interval between doses, or both.

    “These differences may be related to higher antigen content in the mRNA-1273 vaccine, a longer recommended interval between vaccine doses (4 weeks for mRNA-1273 and 3 weeks for BNT162b2), or both.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductreasoning

    The measures of progression to high severity (death, organ failures, oxygen use, duration of hospitalization) capture life-threatening complications of COVID-19, though they do not comprehensively characterize disease severity.

    “Second, progression of COVID-19 to high severity was measured with multiple outcomes that considered death, organ failures, oxygen use, and duration of hospitalization.Although these measures do not comprehensively characterize disease severity, they capture life-threatening complications of COVID-19.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Premisecitation

    mRNA COVID-19 vaccines, including mRNA-1273 and BNT162b2, are highly effective at preventing SARS-CoV-2 infection and COVID-19 hospitalization.

    “The messenger RNA (mRNA) COVID-19 vaccines, including mRNA-1273 (Moderna) and BNT162b2 (Pfizer-BioNTech), are highly effective for preventing SARS-CoV-2 infections and COVID-19 hospitalizations.[2][3][4][5]”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [2][3][4][5]

      Not checked in the free run.

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    If vaccine breakthrough cases were systematically more likely to be hospitalized for COVID-19 of lesser severity than unvaccinated patients, the analyses of the association between vaccination and severe disease could be confounded by admission bias.

    “Fourth, if vaccine breakthrough cases were systematically more likely to be hospitalized for COVID-19 of lesser severity than unvaccinated patients, our analyses of the association between vaccination and severe disease could be confounded by an admission bias.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductown data

    The study used a test-negative case-control design to assess the association between COVID-19 hospitalization and prior mRNA vaccination.

    “We used a test-negative case-control design to assess the association between hospitalization for COVID-19 and prior vaccination with an mRNA COVID-19 vaccine.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [17][18][19]

      Not checked in the free run.

  • May combine two claims.

    Interpretationown data

    COVID-19 mRNA vaccines may attenuate disease severity among patients who develop COVID-19 despite vaccination, consistent with risk reduction of severe COVID-19 among breakthrough infections.

    “These data suggest that the COVID-19 mRNA vaccines may attenuate disease severity among patients who develop COVID-19 despite vaccination, and the total benefits of vaccination exceed those estimated from the prevention of hospitalization alone.”
    • Also stated in: § Conclusions · plain
      “These findings are consistent with risk reduction of developing severe COVID-19 among vaccine breakthrough infections compared with absence of vaccination.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    Vaccination status information was not collected until after patients were enrolled.

    “Information on vaccination status was not collected until after patients were enrolled.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    This analysis included only hospitalized patients and cannot inform whether vaccination attenuates COVID-19 severity among outpatients.

    “Third, this analysis included only hospitalized patients and cannot inform whether vaccination attenuates COVID-19 severity among outpatients.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductnone given

    The study followed STROBE reporting guidelines.

    “STROBE guidelines for reporting were followed.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Study design and conductown data

    Among fully vaccinated patients, 98.0% had source documentation of vaccine doses and 2.0% had only plausible self-report.

    “1666 (98.0%) vaccinated patients had source documentation of vaccine doses and 34 (2.0%) had plausible self-report only.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationown data

    The study population represented typical hospitalized patients in the US, including high prevalence of medical comorbidities and multimorbidity.

    “Moreover, disease progression to critical illness after hospital admission was associated with a lower likelihood of vaccination among a population representing typical hospitalized patients in the US, which included high prevalence of medical comorbidities and multimorbidity.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationown data

    Vaccination with an mRNA COVID-19 vaccine was significantly less likely among patients hospitalized with COVID-19 and among those whose disease progressed to death or mechanical ventilation.

    “Vaccination with an mRNA COVID-19 vaccine was significantly less likely among patients with COVID-19 hospitalization and disease progression to death or mechanical ventilation.”
    • Also stated in: § Discussion · plain
      “vaccination with an mRNA COVID-19 vaccine was significantly less likely among patients with COVID-19 than other conditions and among those with COVID-19 who progressed to death or mechanical ventilation than those with COVID-19 who did not have disease progression.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The multivariable models removed confounding well enough for the reported vaccination–hospitalization and vaccination–progression associations to be valid.
20 of 20

  • The paper relies on this without support.

    Before this study, it was unclear how prior vaccination related to worsening COVID-19 after hospitalization.

    “However, the association between prior vaccination and disease progression to the most severe forms of COVID-19 is not well understood.”

  • The paper relies on this without support.

    The multivariable models removed confounding well enough for the reported vaccination–hospitalization and vaccination–progression associations to be valid.

    “A mixed-effects logistic regression model was generated, treating enrolling site as a random effect and with the following covariables: admission date (biweekly intervals), age, sex, and race and ethnicity.”

  • The paper relies on this without support.

    The Alpha variant preceded Delta circulation, so patients infected with Delta were more likely to have been vaccinated longer ago.

    “These issues are epidemiologically challenging to disentangle with certainty because the Alpha variant preceded Delta circulation, and thus patients infected with the Delta variant also were more likely to have been vaccinated longer ago.”

  • The paper relies on this without support.

    The Delta variant predominated during July-August 2021.

    “between March and June when the Alpha variant circulated vs July and August when the Delta variant predominated.”

  • The paper relies on this without support.

    The Alpha variant circulated during March-June 2021.

    “between March and June when the Alpha variant circulated vs July and August when the Delta variant predominated.”
5 of 5

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References 36 · Cited by 633

Research works printed but not linked: 20

  1. Morin, 2021, Four-month clinical status of a cohort of patients after hospitalization for COVID-19., JAMA, 325, 1525, 10.1001/jama.2021.3331 · DOI
  2. Tenforde, 2021, Effectiveness of SARS-CoV-2 mRNA vaccines for preventing Covid-19 hospitalizations in the United States., Clin Infect Dis
  3. Goldshtein, 2021, Association between BNT162b2 vaccination and incidence of SARS-CoV-2 infection in pregnant women., JAMA, 326, 728, 10.1001/jama.2021.11035 · DOI
  4. Halloran, 1999, Design and interpretation of vaccine field studies., Epidemiol Rev, 21, 73, 10.1093/oxfordjournals.epirev.a017990 · DOI
  5. WHO Working Group on the Clinical Characterisation and Management of COVID-19 infection, 2020, A minimal common outcome measure set for COVID-19 clinical research., Lancet Infect Dis, 20, e192, 10.1016/S1473-3099(20)30483-7 · DOI
  6. Sheikh, 2021, SARS-CoV-2 Delta VOC in Scotland: demographics, risk of hospital admission, and vaccine effectiveness., Lancet, 397, 2461, 10.1016/S0140-6736(21)01358-1 · DOI · Paper page
  7. Thompson, 2021, Prevention and attenuation of Covid-19 with the BNT162b2 and mRNA-1273 vaccines., N Engl J Med, 385, 320, 10.1056/NEJMoa2107058 · DOI
  8. Cromer, 2021, Prospects for durable immune control of SARS-CoV-2 and prevention of reinfection., Nat Rev Immunol, 21, 395, 10.1038/s41577-021-00550-x · DOI · Paper page
  9. Patel, 2020, Change in antibodies to SARS-CoV-2 over 60 days among health care personnel in Nashville, Tennessee., JAMA, 324, 1781, 10.1001/jama.2020.18796 · DOI
  10. Self, 2021, Comparative effectiveness of Moderna, Pfizer-BioNTech, and Janssen (Johnson & Johnson) vaccines in preventing COVID-19 hospitalizations among adults without immunocompromising conditions—United States, March-August 2021., MMWR Morb Mortal Wkly Rep, 70, 1337, 10.15585/mmwr.mm7038e1 · DOI · Paper page
  11. Grijalva, 2021, Influenza vaccine effectiveness for prevention of severe influenza-associated illness among adults in the United States, 2019-2020: a test-negative study., Clin Infect Dis
  12. Tenforde, 2021, Influenza vaccine effectiveness against hospitalization in the United States, 2019-2020., J Infect Dis., 224, 813, 10.1093/infdis/jiaa800 · DOI
  13. Grijalva, 2015, Association between hospitalization with community-acquired laboratory-confirmed influenza pneumonia and prior receipt of influenza vaccination., JAMA, 314, 1488, 10.1001/jama.2015.12160 · DOI
  14. Lewnard, 2021, Theoretical framework for retrospective studies of the effectiveness of SARS-CoV-2 vaccines., Epidemiology, 32, 508, 10.1097/EDE.0000000000001366 · DOI · Paper page
  15. Foppa, 2013, The case test-negative design for studies of the effectiveness of influenza vaccine., Vaccine, 31, 3104, 10.1016/j.vaccine.2013.04.026 · DOI
  16. Nanduri, 2021, Effectiveness of Pfizer-BioNTech and Moderna vaccines in preventing SARS-CoV-2 infection among nursing home residents before and during widespread circulation of the SARS-CoV-2 B.1.617.2 (Delta) variant—National Healthcare Safety Network, March 1–August 1, 2021., MMWR Morb Mortal Wkly Rep, 70, 1163, 10.15585/mmwr.mm7034e3 · DOI
  17. Grannis, 2021, Interim estimates of COVID-19 vaccine effectiveness against COVID-19–associated emergency department or urgent care clinic encounters and hospitalizations among adults during SARS-CoV-2 B.1.617.2 (Delta) variant predominance—nine states, June-August 2021., MMWR Morb Mortal Wkly Rep, 70, 1291, 10.15585/mmwr.mm7037e2 · DOI
  18. Steensels, 2021, Comparison of SARS-CoV-2 antibody response following vaccination with BNT162b2 and mRNA-1273., JAMA, 10.1001/jama.2021.15125 · DOI · Paper page
  19. Flannery, 2020, Spread of antigenically drifted influenza A(H3N2) viruses and vaccine effectiveness in the United States during the 2018-2019 season., J Infect Dis, 221, 8, 10.1093/infdis/jiz543 · DOI
  20. Quick? J. nCoV2-2019 sequencing protocol v3 (LoCost) V.3. protocols.io. Accessed May 26, 2021. https://www.protocols.io/view/ncov-2019-sequencing-protocol-%20v3-locost-bh42j8ye · DOI

Authors
Tenforde, M. W., Self, W. H., Adams, K., Gaglani, M., Ginde, A. A., McNeal, T., Ghamande, S., Douin, D. J., Talbot, H. K., Casey, J. D., Mohr, N. M., Zepeski, A., Shapiro, N. I., Gibbs, K. W., Files, D. C., Hager, D. N., Shehu, A., Prekker, M. E., Erickson, H. L., Exline, M. C., Gong, M. N., Mohamed, A., Henning, D. J., Steingrub, J. S., Peltan, I. D., Brown, S. M., Martin, E. T., Monto, A. S., Khan, A., Hough, C. L., Busse, L. W., ten Lohuis, C. C., Duggal, A., Wilson, J. G., Gordon, A. J., Qadir, N., Chang, S. Y., Mallow, C., Rivas, C., Babcock, H. M., Kwon, J. H., Halasa, N., Chappell, J. D., Lauring, A. S., Grijalva, C. G., Rice, T. W., Jones, I. D., Stubblefield, W. B., Baughman, A., Womack, K. N., Rhoads, J. P., Lindsell, C. J., Hart, K. W., Zhu, Y., Olson, S. M., Kobayashi, M., Verani, J. R., Patel, M. M., & Influenza and Other Viruses in the Acutely Ill (IVY) Network
Affiliations
  • Centers for Disease Control and Prevention (US)
  • Vanderbilt University (US)
  • Baylor Scott & White Medical Center - Temple (US)
  • University of Colorado Anschutz (US)
  • Vanderbilt University Medical Center (US)
  • University of Iowa (US)
  • Beth Israel Deaconess Medical Center (US)
  • Wake Forest University Health Sciences (US)
  • Johns Hopkins University (US)
  • Hennepin County Medical Center (US)
  • The Ohio State University (US)
  • Albert Einstein College of Medicine (US)
  • University of Washington (US)
  • Baystate Medical Center (US)
  • University of Utah (US)
  • University of Michigan (US)
  • Oregon Health & Science University (US)
  • Emory University (US)
  • Emory Critical Care Center, Emory Healthcare, Atlanta, Georgia
  • Cleveland Clinic (US)
  • Stanford Medicine (US)
  • University of California, Los Angeles (US)
  • University of Miami (US)
  • Washington University in St. Louis (US)
Corresponding author
Tenforde, Mark W.
ORCID
Venue
JAMA
Publisher
American Medical Association (AMA)
Published
2021-11-23
Volume
326
Issue
20
Pages
2043
ISSN
  • 0002-9955 (ISSN-L)
  • 0098-7484
DOI
10.1001/jama.2021.19499
PMC
PMC8569602
OpenAlex
W3208400521
Cited by
633
References
36
Citations by year
2026: 15 · 2025: 66 · 2024: 109 · 2023: 197 · 2022: 231 · 2021: 15
FWCI
44.26
Type
journal article
Language
en
Open access
Locations
  • JAMA (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Heart, Lung, and Blood Institute (T32HL087738)
  • National Institute of General Medical Sciences (K23GM129661, T32GM135169)
  • National Institute of Allergy and Infectious Diseases (K24AI148459)
Topics
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
  • Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
  • Social Sciences › Health › Vaccine Coverage and Hesitancy
Keywords
COVID-19 mRNA vaccine, COVID-19 hospitalization, disease severity, breakthrough infection, Moderna mRNA-1273, BNT162b2, SARS-CoV-2 Alpha variant, mechanical ventilation, COVID-19 mortality, hospitalized patients, vaccine effectiveness, immunocompromised patients, racial disparities in vaccination
MeSH terms
COVID-19, SARS-CoV-2, COVID-19 Vaccines, BNT162 Vaccine, 2019-nCoV Vaccine mRNA-1273, Breakthrough Infections, Adult, Aged, Female, Hospitalization, Humans, Male, Middle Aged, Respiration, Artificial, Severity of Illness Index, Vaccination, Case-Control Studies, Disease Progression

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