Sustained Effectiveness of Pfizer-BioNTech and Moderna Vaccines Against COVID-19 Associated Hospitalizations Among Adults — United States, March–July 2021
Authors: Mark W. Tenforde, Wesley H. Self, Eric A. Naioti, Adit A. Ginde, David J. Douin, Samantha M. Olson, H. Keipp Talbot, Jonathan D. Casey, Nicholas M. Mohr, Anne Zepeski, Manjusha Gaglani, Tresa McNeal, Shekhar Ghamande, Nathan I. Shapiro, Kevin W. Gibbs, D. Clark Files, David N. Hager, Arber Shehu, Matthew E. Prekker, Heidi L. Erickson, Michelle N. Gong, Amira Mohamed, Daniel J. Henning, Jay S. Steingrub, Ithan D. Peltan, Samuel M. Brown, Emily T. Martin, Arnold S. Monto, Akram Khan, Catherine L. Hough, Laurence W. Busse, Caitlin C. ten Lohuis, Abhijit Duggal, Jennifer G. Wilson, Alexandra June Gordon, Nida Qadir, Steven Y. Chang, Christopher Mallow, Carolina Rivas, Hilary M. Babcock, Jennie H. Kwon, Matthew C. Exline, Natasha Halasa, James D. Chappell, Adam S. Lauring, Carlos G. Grijalva, Todd W. Rice, Ian D. Jones, William B. Stubblefield, Adrienne Baughman, Kelsey N. Womack, Christopher J. Lindsell, Kimberly W. Hart, Yuwei Zhu, Meagan Stephenson, Stephanie J. Schrag, Miwako Kobayashi, Jennifer R. Verani, Manish M. Patel, Nicole Calhoun, Kempapura Murthy, Judy Herrick, Amanda McKillop, Eric Hoffman, Martha Zayed, Michael Smith, Natalie Settele, Jason Ettlinger, Elisa Priest, Jennifer Thomas, Alejandro Arroliga, Madhava Beeram, Ryan Kindle, Lori-Ann Kozikowski, Lesley De Souza, Scott Ouellette, Sherell Thornton-Thompson, Patrick Tyler, Omar Mehkri, Kiran Ashok, Susan Gole, Alexander King, Bryan Poynter, Nicholas Stanley, Audrey Hendrickson, Ellen Maruggi, Tyler Scharber, Jeffrey Jorgensen, Robert Bowers, Jennifer King, Valerie Aston, Brent Armbruster, Richard E. Rothman, Rahul Nair, Jen-Ting (Tina) Chen, Sarah Karow, Emily Robart, Paulo Nunes Maldonado, Maryiam Khan, Preston So, Joe Levitt, Cynthia Perez, Anita Visweswaran, Jonasel Roque, Adreanne Rivera, Trevor Frankel, Michelle Howell, Jennifer Friedel, Jennifer Goff, David Huynh, Michael Tozier, Conner Driver, Michael Carricato, Alexandra Foster, Paul Nassar, Lori Stout, Zita Sibenaller, Alicia Walter, Jasmine Mares, Logan Olson, Bradley Clinansmith, Carolina Rivas, Hayley Gershengorn, EJ McSpadden, Rachel Truscon, Anne Kaniclides, Lara Thomas, Ramsay Bielak, Weronika Damek Valvano, Rebecca Fong, William J. Fitzsimmons, Christopher Blair, Andrew L. Valesano, Julie Gilbert, Christine D. Crider, Kyle A. Steinbock, Thomas C. Paulson, Layla A. Anderson, Christy Kampe, Jakea Johnson, Rendie McHenry, Marcia Blair, Douglas Conway, Mary LaRose, Leigha Landreth, Madeline Hicks, Lisa Parks, Jahnavi Bongu, David McDonald, Candice Cass, Sondra Seiler, David Park, Tiffany Hink, Meghan Wallace, Carey-Ann Burnham, Olivia G. Arter
Journal: MMWR Morbidity and Mortality Weekly Report (2021)

Real-world evaluations have demonstrated high effectiveness of vaccines against COVID-19-associated hospitalizations (1-4) measured shortly after vaccination; longer follow-up is needed to assess durability of protection. In an evaluation at 21 hospitals in 18 states, the duration of mRNA vaccine (Pfizer-BioNTech or Moderna) effectiveness (VE) against COVID-19-associated hospitalizations was assessed among adults aged ≥18 years. Among 3,089 hospitalized adults (including 1,194 COVID-19 case-patients and 1,895 non-COVID-19 control-patients), the median age was 59 years, 48.7% were female, and 21.1% had an immunocompromising condition. Overall, 141 (11.8%) case-patients and 988 (52.1%) controls were fully vaccinated (defined as receipt of the second dose of Pfizer-BioNTech or Moderna mRNA COVID-19 vaccines ≥14 days before illness onset), with a median interval of 65 days (range = 14-166 days) after receipt of second dose. VE against COVID-19-associated hospitalization during the full surveillance period was 86% (95% confidence interval [CI] = 82%-88%) overall and 90% (95% CI = 87%-92%) among adults without immunocompromising conditions. VE against COVID-19- associated hospitalization was 86% (95% CI = 82%-90%) 2-12 weeks and 84% (95% CI = 77%-90%) 13-24 weeks from receipt of the second vaccine dose, with no significant change between these periods (p = 0.854). Whole genome sequencing of 454 case-patient specimens found that 242 (53.3%) belonged to the B.1.1.7 (Alpha) lineage and 74 (16.3%) to the B.1.617.2 (Delta) lineage. Effectiveness of mRNA vaccines against COVID-19-associated hospitalization was sustained over a 24-week period, including among groups at higher risk for severe COVID-19; ongoing monitoring is needed as new SARS-CoV-2 variants emerge. To reduce their risk for hospitalization, all eligible persons should be offered COVID-19 vaccination.