Sustained Effectiveness of Pfizer-BioNTech and Moderna Vaccines Against COVID-19 Associated Hospitalizations Among Adults — United States, March–July 2021

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

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.