Effectiveness of mRNA vaccines in preventing COVID-19 hospitalization by age and burden of chronic medical conditions among immunocompetent US adults, March-August 2021. The Journal of infectious diseases Lewis, N. M., Naioti, E. A., Self, W. H., Ginde, A. A., Douin, D. J., Talbot, H. K., Casey, J. D., Mohr, N. M., Zepeski, A., Gaglani, M., Ghamande, S. A., McNeal, T. A., Shapiro, N. I., Gibbs, K. W., Files, D. C., Hager, D. N., Shehu, A., Prekker, M. E., Erickson, H. L., Gong, M. N., Mohamed, A., Henning, D. J., Steingrub, J. S., Peltan, I. D., Brown, S. M., Martin, E. T., Hubel, K., 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., Exline, M. C., Halasa, N., Chappell, J. D., Lauring, A. S., Grijalva, C. G., Rice, T. W., Rhoads, J. P., Stubblefield, W. B., Baughman, A., Womack, K. N., Lindsell, C. J., Hart, K. W., Zhu, Y., Schrag, S. J., Kobayashi, M., Verani, J. R., Patel, M. M., Tenforde, M. W. 1800


In a multi-state network, vaccine effectiveness (VE) against COVID-19 hospitalizations was evaluated among immunocompetent adults (=18-years) during March-August 2021 using a case-control design. Among 1669 hospitalized COVID-19 cases (11% fully vaccinated) and 1950 RT-PCR-negative controls (54% fully vaccinated), VE was higher at 96% (95% CI: 93-98%) among patients with no chronic medical conditions than patients with =3 categories of conditions (83% [95% CI: 76-88%]). VE was similar between those aged 18-64 years vs =65 years (p>0.05). Vaccine effectiveness against severe COVID-19 was very high among adults without chronic conditions and lessened with increasing burden of comorbidities.

View details for DOI 10.1093/infdis/jiab619

View details for PubMedID 34932114