Early Estimates of Bivalent mRNA Vaccine Effectiveness in Preventing COVID-19–Associated Emergency Department or Urgent Care Encounters and Hospitalizations Among Immunocompetent Adults — VISION Network, Nine States, September–November 2022
Mark W. Tenforde, Zachary A. Weber, Karthik Natarajan, Nicola P. Klein, Anupam B. Kharbanda, Edward Stenehjem, Peter J. Embí, Sarah E. Reese, Allison L. Naleway, Shaun J. Grannis, Malini B. DeSilva, Toan C. Ong, Manjusha Gaglani, Jungmi Han, Monica Dickerson, Bruce Fireman, Kristin Dascomb, Stephanie A. Irving, Gabriela Vazquez‐Benitez, Suchitra Rao, Deepika Konatham, Palak Patel, Kristin E. Schrader, Ned Lewis, Nancy Grisel, Charlene McEvoy, Kempapura Murthy, Eric P. Griggs, Elizabeth Rowley, Ousseny Zerbo, Julie Arndorfer, Margaret M. Dunne, Kristin Goddard, Caitlin Ray, Yan Zhuang, Julius Timbol, Morgan Najdowski, Duck‐Hye Yang, John Hansen, Sarah W. Ball, Ruth Link‐Gelles
Abstract
VE of a bivalent booster dose (after 2, 3, or 4 monovalent doses) against COVID-19-associated ED/UC encounters was 56% compared with no vaccination, 31% compared with monovalent vaccination only with last dose 2-4 months earlier, and 50% compared with monovalent vaccination only with last dose ≥11 months earlier. VE of a bivalent booster dose (after 2, 3, or 4 monovalent doses) against COVID-19-associated hospitalizations was 57% compared with no vaccination, 38% compared with monovalent vaccination only with last dose 5-7 months earlier, and 45% compared with monovalent vaccination only with last dose ≥11 months earlier. Bivalent vaccines administered after 2, 3, or 4 monovalent doses were effective in preventing medically attended COVID-19 compared with no vaccination and provided additional protection compared with past monovalent vaccination only, with relative protection increasing with time since receipt of the last monovalent dose. All eligible persons should stay up to date with recommended COVID-19 vaccinations, including receiving a bivalent booster dose. Persons should also consider taking additional precautions to avoid respiratory illness this winter season, such as masking in public indoor spaces, especially in areas where COVID-19 community levels are high.