Interim Estimates of 2024–2025 Seasonal Influenza Vaccine Effectiveness — Four Vaccine Effectiveness Networks, United States, October 2024–February 2025
Authors: Aaron M. Frutos, Seana Cleary, Emily L. Reeves, Haris M. Ahmad, Ashley M. Price, Wesley H. Self, Yuwei Zhu, Basmah Safdar, Ithan D. Peltan, Kevin W. Gibbs, Matthew C. Exline, Adam S. Lauring, Sarah W. Ball, Malini DeSilva, Sara Y. Tartof, Kristin Dascomb, Stephanie A. Irving, Nicola P. Klein, Brian E. Dixon, Toan C. Ong, Ivana A. Vaughn, Stacey L. House, Kiran A. Faryar, Mary Patricia Nowalk, Manjusha Gaglani, Karen J. Wernli, Vel Murugan, Olivia L. Williams, Rangaraj Selvarangan, Geoffrey A. Weinberg, Mary A. Staat, Natasha B. Halasa, Leila C. Sahni, Marian G. Michaels, Janet A. Englund, Marie K. Kirby, Diya Surie, Fatimah S. Dawood, Benjamin R. Clopper, Heidi L. Moline, Ruth Link-Gelles, Amanda B. Payne, Elizabeth Harker, Kristina Wielgosz, Zachary A. Weber, Duck-Hye Yang, Nathaniel M. Lewis, Jennifer DeCuir, Samantha M. Olson, Jessie R. Chung, Brendan Flannery, Lisa A. Grohskopf, Carrie Reed, Shikha Garg, Sascha Ellington, Laurence W. Busse, Cristie Columbus, Abhijit Duggal, Adit A. Ginde, Michelle N. Gong, David N. Hager, Estelle Harris, Cassandra Johnson, Nicholas J. Johnson, Akram Khan, Jennie H. Kwon, Christopher Mallow, Nicholas M. Mohr, Jarrod M. Mosier, Matthew E. Prekker, Nida Qadir, Colleen Ratcliff, Nathan I. Shapiro, Jay S. Steingrub, Jennifer G. Wilson, Omobosola Akinsete, Michelle Barron, Daniel Bride, Tom Duszynski, Shaun Grannis, John Hansen, Padma Koppolu, David Mayer, Charlene McEvoy, Allison L. Naleway, S. Bianca Salas, Tamara Sheffield, Lina S. Sy, Ousseny Zerbo, Julie A. Boom, Megan Freeman, Eileen J. Klein, Mary E. Moffatt, Daniel C. Payne, Pedro A. Piedra, Elizabeth P. Schlaudecker, Jennifer E. Schuster, Laura S. Stewart, Peter G. Szilagyi, John V. Williams, Danielle M. Zerr, G.K. Balasubramani, Natalie A. B. Bontrager, Tara Curley, Curtis Donskey, Juliana DaSilva, Britan Fairall, Krissy Moehling Geffel, Claudia Hoyen, Lisa M. Keong, Erika Kiniry, Aleda M. Leis, Emily T. Martin, Jamie Mills, Lora Nordstrom, Leah Odame-Bamfo, C. Hallie Phillips, Emmanuel B. Walter, Karen Yeager
Journal: MMWR Morbidity and Mortality Weekly Report (2025)

Annual influenza vaccination is recommended for all persons aged ≥6 months in the United States. Interim influenza vaccine effectiveness (VE) was calculated among patients with acute respiratory illness-associated outpatient visits and hospitalizations from four VE networks during the 2024-25 influenza season (October 2024-February 2025). Among children and adolescents aged <18 years, VE against any influenza was 32%, 59%, and 60% in the outpatient setting in three networks, and against influenza-associated hospitalization was 63% and 78% in two networks. Among adults aged ≥18 years, VE in the outpatient setting was 36% and 54% in two networks and was 41% and 55% against hospitalization in two networks. Preliminary estimates indicate that receipt of the 2024-2025 influenza vaccine reduced the likelihood of medically attended influenza and influenza-associated hospitalization. CDC recommends annual receipt of an age-appropriate influenza vaccine by all eligible persons aged ≥6 months as long as influenza viruses continue to circulate locally.