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Effectiveness of SARS-CoV-2 mRNA Vaccines for Preventing Covid-19 Hospitalizations in the United States. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America Tenforde, M. W., Patel, M. M., Ginde, A. A., Douin, D. J., Talbot, H. K., Casey, J. D., Mohr, N. M., Zepeski, A., Gaglani, M., McNeal, T., Ghamande, S., 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., Peltan, I. D., Brown, S. M., Martin, E. T., Monto, A. S., Khan, A., Hough, C. T., Busse, L., Ten Lohuis, C. C., Duggal, A., Wilson, J. G., Gordon, A. J., Qadir, N., Chang, S. Y., Mallow, C., Gershengorn, H. B., 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., Lindsell, C. J., Hart, K. W., Zhu, Y., Olson, S. M., Stephenson, M., Schrag, S. J., Kobayashi, M., Verani, J. R., Self, W. H., Influenza and Other Viruses in the Acutely Ill (IVY) Network 2021

Abstract

BACKGROUND: As SARS-CoV-2 vaccination coverage increases in the United States (US), there is a need to understand the real-world effectiveness against severe Covid-19 and among people at increased risk for poor outcomes.METHODS: In a multicenter case-control analysis of US adults hospitalized March 11-May 5, 2021, we evaluated vaccine effectiveness to prevent Covid-19 hospitalizations by comparing odds of prior vaccination with an mRNA vaccine (Pfizer-BioNTech or Moderna) between cases hospitalized with Covid-19 and hospital-based controls who tested negative for SARS-CoV-2.RESULTS: Among 1212 participants, including 593 cases and 619 controls, median age was 58 years, 22.8% were Black, 13.9% were Hispanic, and 21.0% had immunosuppression. SARS-CoV-2 lineage B.1.1.7 (Alpha) was the most common variant (67.9% of viruses with lineage determined). Full vaccination (receipt of two vaccine doses =14 days before illness onset) had been received by 8.2% of cases and 36.4% of controls. Overall vaccine effectiveness was 87.1% (95% CI: 80.7 to 91.3%). Vaccine effectiveness was similar for Pfizer-BioNTech and Moderna vaccines, and highest in adults aged 18-49 years (97.4%; 95% CI: 79.3 to 99.7%). Among 45 patients with vaccine-breakthrough Covid hospitalizations, 44 (97.8%) were =50 years old and 20 (44.4%) had immunosuppression. Vaccine effectiveness was lower among patients with immunosuppression (62.9%; 95% CI: 20.8 to 82.6%) than without immunosuppression (91.3%; 95% CI: 85.6 to 94.8%).CONCLUSION: During March-May 2021, SARS-CoV-2 mRNA vaccines were highly effective for preventing Covid-19 hospitalizations among US adults. SARS-CoV-2 vaccination was beneficial for patients with immunosuppression, but effectiveness was lower in the immunosuppressed population.

View details for DOI 10.1093/cid/ciab687

View details for PubMedID 34358310