{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T11:22:05Z","timestamp":1793013725251,"version":"4.5.0"},"reference-count":26,"publisher":"Oxford University Press (OUP)","issue":"4","funder":[{"DOI":"10.13039\/100000030","name":"US Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["1U01 IP001180-01"],"award-info":[{"award-number":["1U01 IP001180-01"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000030","name":"US Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["1U01 IP001181-01"],"award-info":[{"award-number":["1U01 IP001181-01"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000030","name":"US Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["1U01 IP001182-01"],"award-info":[{"award-number":["1U01 IP001182-01"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000030","name":"US Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["1U01 IP001184-01"],"award-info":[{"award-number":["1U01 IP001184-01"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000030","name":"US Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["1U01 IP001189-01"],"award-info":[{"award-number":["1U01 IP001189-01"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000030","name":"US Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["1U01 IP001191-01"],"award-info":[{"award-number":["1U01 IP001191-01"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000030","name":"US Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["1U01 IP001193-01"],"award-info":[{"award-number":["1U01 IP001193-01"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000030","name":"US Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["1U01 IP001194-01"],"award-info":[{"award-number":["1U01 IP001194-01"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["UL1TR001857"],"award-info":[{"award-number":["UL1TR001857"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,11,6]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The 2023\u20132024 US influenza season was characterized by a predominance of A(H1N1)pdm09 virus circulation with cocirculation of A(H3N2) and B\/Victoria viruses. We estimated vaccine effectiveness (VE) in the United States against mild-to-moderate medically attended influenza illness in the 2023\u20132024 season.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We enrolled outpatients aged \u22658 months with acute respiratory illness in 7 states. Respiratory specimens were tested for influenza type\/subtype by reverse-transcriptase polymerase chain reaction. Influenza VE was estimated with a test-negative design comparing odds of testing positive for influenza among vaccinated versus unvaccinated participants. We estimated VE by virus subtype\/lineage and A(H1N1)pdm09 genetic subclades.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among 6629 enrolled patients, 1780 (27%) tested positive for influenza, including 806 with A(H1N1)pdm09, 567 with B\/Victoria, and 328 with A(H3N2). VE against any influenza illness was 44% (95% confidence interval, 36%\u201351%): 29% (15%\u201341%) against influenza A(H1N1)pdm09, 74% (65%\u201381%) against B\/Victoria, and 30% (8%\u201347%) against A(H3N2). Statistically significant protection against any influenza was found for all age groups except adults aged 50\u201364 years. Lack of protection in this age group was specific to influenza A\u2013associated illness. We observed differences in VE by birth cohort and A(H1N1)pdm09 virus genetic subclade.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Vaccination reduced outpatient medically attended influenza overall by 44% and provided protection overall against circulating influenza A and B viruses. Serologic studies would help inform differences observed by age groups.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/cid\/ciae658","type":"journal-article","created":{"date-parts":[[2025,1,2]],"date-time":"2025-01-02T15:20:20Z","timestamp":1735831220000},"page":"e184-e191","source":"Crossref","is-referenced-by-count":37,"title":["Influenza Vaccine Effectiveness Against Medically Attended Outpatients Illness, United States, 2023\u20132024 Season"],"prefix":"10.1093","volume":"81","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5205-966X","authenticated-orcid":false,"given":"Jessie R","family":"Chung","sequence":"first","affiliation":[{"name":"Influenza Division, US Centers for Disease Control and Prevention , Atlanta, Georgia ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ashley M","family":"Price","sequence":"additional","affiliation":[{"name":"Influenza Division, US Centers for Disease Control and Prevention , Atlanta, Georgia ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5941-6092","authenticated-orcid":false,"given":"Richard K","family":"Zimmerman","sequence":"additional","affiliation":[{"name":"Department of Family Medicine, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2103-4096","authenticated-orcid":false,"given":"Krissy","family":"Moehling Geffel","sequence":"additional","affiliation":[{"name":"Department of Family Medicine, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stacey L","family":"House","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Washington University School of Medicine in St Louis , St Louis, Missouri ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tara","family":"Curley","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Washington University School of Medicine in St Louis , St Louis, Missouri ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7945-0327","authenticated-orcid":false,"given":"Karen J","family":"Wernli","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Washington Health Research Institute , Seattle, Washington ,","place":["USA"]},{"name":"Department of Health System Science, Kaiser Permanente Bernard J. Tyson School of Medicine , Pasadena, California ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C Hallie","family":"Phillips","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Washington Health Research Institute , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emily T","family":"Martin","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, University of Michigan School of Public Health , Ann Arbor, Michigan ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7201-0289","authenticated-orcid":false,"given":"Ivana A","family":"Vaughn","sequence":"additional","affiliation":[{"name":"Department of Public Health Sciences, Henry Ford Health , Detroit, Michigan ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7368-7742","authenticated-orcid":false,"given":"Vel","family":"Murugan","sequence":"additional","affiliation":[{"name":"Biodesign Center for Personalized Diagnostics and College of Health Solutions, Arizona State University , Tempe, Arizona ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5100-9724","authenticated-orcid":false,"given":"Matthew","family":"Scotch","sequence":"additional","affiliation":[{"name":"Biodesign Center for Personalized Diagnostics and College of Health Solutions, Arizona State University , Tempe, Arizona ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2514-3820","authenticated-orcid":false,"given":"Elie A","family":"Saade","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases and HIV Medicine and Department of Emergency Medicine, University Hospitals of Cleveland , Cleveland, Ohio ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8466-9796","authenticated-orcid":false,"given":"Kiran A","family":"Faryar","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases and HIV Medicine and Department of Emergency Medicine, University Hospitals of Cleveland , Cleveland, Ohio ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3952-9230","authenticated-orcid":false,"given":"Manjusha","family":"Gaglani","sequence":"additional","affiliation":[{"name":"Center for Research in Vaccines and Infections, Baylor Scott & White Health , Temple, Texas ,","place":["USA"]},{"name":"Department of Pediatrics and Department of Family Medicine, Baylor College of Medicine , Temple, Texas ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jason D","family":"Ramm","sequence":"additional","affiliation":[{"name":"Center for Research in Vaccines and Infections, Baylor Scott & White Health , Temple, Texas ,","place":["USA"]},{"name":"Department of Pediatrics and Department of Family Medicine, Baylor College of Medicine , Temple, Texas ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olivia L","family":"Williams","sequence":"additional","affiliation":[{"name":"Duke Human Vaccine Institute, Duke University School of Medicine , Durham, North Carolina ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emmanuel B","family":"Walter","sequence":"additional","affiliation":[{"name":"Duke Human Vaccine Institute, Duke University School of Medicine , Durham, North Carolina ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0859-9604","authenticated-orcid":false,"given":"Marie K","family":"Kirby","sequence":"additional","affiliation":[{"name":"Influenza Division, US Centers for Disease Control and Prevention , Atlanta, Georgia ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8211-659X","authenticated-orcid":false,"given":"Lisa M","family":"Keong","sequence":"additional","affiliation":[{"name":"Influenza Division, US Centers for Disease Control and Prevention , Atlanta, Georgia ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rebecca","family":"Kondor","sequence":"additional","affiliation":[{"name":"Influenza Division, US Centers for Disease Control and Prevention , Atlanta, Georgia 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