{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,12]],"date-time":"2026-11-12T12:40:18Z","timestamp":1794487218407,"version":"4.9.1"},"reference-count":19,"publisher":"American Medical Association (AMA)","issue":"6","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JAMA Netw Open"],"abstract":"\n Importance<\/jats:title>\n The 2025-2026 COVID-19 vaccine, targeting JN.1 and JN.1-derived sublineages, became available in the US in September 2025.<\/jats:p>\n <\/jats:sec>\n \n Objective<\/jats:title>\n To assess the estimated interim effectiveness of 2025-2026 COVID-19 vaccines against medically attended COVID-19 among immunocompetent adults aged 18 years or older in the US.<\/jats:p>\n <\/jats:sec>\n \n Design, Setting, and Participants<\/jats:title>\n This case-control study used a test-negative design to investigate patient encounters captured in the Virtual SARS-CoV-2, Influenza, and Other Respiratory Viruses Network, an electronic medical record\u2013based network of health care systems (253 emergency departments\/urgent cares [ED\/UCs] and 179 hospitals in 7 states) from September 3, 2025, to December 31, 2025. Patient encounters with COVID-19\u2013like illness and a molecular or antigen SARS-CoV-2 test 10 days before to 3 days after the encounter date were included.<\/jats:p>\n <\/jats:sec>\n \n Exposure<\/jats:title>\n 2025-2026 COVID-19 vaccination regardless of prior COVID-19 vaccination.<\/jats:p>\n <\/jats:sec>\n \n Main Outcomes and Measures<\/jats:title>\n The main outcomes were COVID-19\u2013associated ED\/UC encounters and COVID-19\u2013associated hospitalizations. Cases were defined as encounters with a positive molecular or antigen SARS-CoV-2 test and controls as encounters with a negative molecular SARS-CoV-2 test. The odds of 2025-2026 COVID-19 vaccination among cases and controls, adjusting for confounders, were compared and used to estimate vaccine effectiveness (VE) as (1\u2009\u2212\u2009adjusted odds ratio)\u2009\u00d7\u2009100%.<\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n In 85\u202f725 ED\/UC encounters among adults aged 18 years and older (51\u202f841 [60%] aged 18-64 years; 51\u202f775 female [60%]), 206 of 3941 cases (5%) and 9453 of 81\u202f784 controls (12%) received a 2025-2026 COVID-19 vaccination. Estimated VE against COVID-19\u2013associated ED\/UC encounters was 50% (95% CI, 42%-57%; median [IQR] time since 2025-2026 COVID-19 vaccine dose receipt, 47 [27-69] days). In 26\u202f073 hospitalizations with a COVID-19\u2013like illness (17\u202f530 [67%] aged \u226565 years; 13\u202f985 female [54%]), 60 of 1022 cases (6%) received a 2025-2026 COVID-19 vaccination compared with 3080 of 25\u202f051 controls (12%). Estimated VE against COVID-19\u2013associated hospitalization was 55% (95% CI, 41%-66%; median [IQR] time since 2025-2026 COVID-19 vaccine dose receipt, 46 [26-68] days). Among patients aged 65 years or older, estimated VE against ED\/UC encounters was 48% (95% CI, 37%-56%; median [IQR] time since dose receipt, 48 [27-69] days; 33\u202f884 encounters) and against hospitalization was 53% (95% CI, 37%-65%; median [IQR] time since dose receipt, 46 [26-69] days; 17\u202f530 hospitalizations).<\/jats:p>\n <\/jats:sec>\n \n Conclusions and Relevance<\/jats:title>\n In this study, receipt of 2025-2026 COVID-19 vaccination was associated with additional protection beyond existing immunity in adults against medically attended COVID-19, including ED\/UC encounters and hospitalizations, compared with no receipt of a 2025-2026 vaccine dose. These findings suggest that adults can reduce their likelihood of severe COVID-19\u2013associated outcomes by obtaining a 2025-2026 COVID-19 vaccination.<\/jats:p>\n <\/jats:sec>","DOI":"10.1001\/jamanetworkopen.2026.25152","type":"journal-article","created":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T16:30:23Z","timestamp":1782232223000},"page":"e2625152","source":"Crossref","is-referenced-by-count":8,"title":["Interim Estimated Effectiveness of 2025-2026 COVID-19 Vaccines in Adults Using a Test-Negative Design"],"prefix":"10.1001","volume":"9","author":[{"given":"Ryan E.","family":"Wiegand","sequence":"first","affiliation":[{"name":"National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sean","family":"Chickery","sequence":"additional","affiliation":[{"name":"Westat, Bethesda, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Duck-Hye","family":"Yang","sequence":"additional","affiliation":[{"name":"Westat, Bethesda, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah W.","family":"Ball","sequence":"additional","affiliation":[{"name":"Westat, Bethesda, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Malini B.","family":"DeSilva","sequence":"additional","affiliation":[{"name":"HealthPartners Institute, Minneapolis, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristin","family":"Dascomb","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases and Clinical Epidemiology, Intermountain Health, Salt Lake City, Utah"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephanie A.","family":"Irving","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Center for Health Research, Portland, Oregon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karthik","family":"Natarajan","sequence":"additional","affiliation":[{"name":"Department of Biomedical Informatics, Columbia University Irving Medical Center, New York, New York"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicola P.","family":"Klein","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California Division of Research, Oakland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaun J.","family":"Grannis","sequence":"additional","affiliation":[{"name":"Center for Biomedical Informatics, Regenstrief Institute, Indianapolis, Indiana"},{"name":"Department of Family Medicine, School of Medicine, Indiana University, Indianapolis"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Toan C.","family":"Ong","sequence":"additional","affiliation":[{"name":"School of Medicine, University of Colorado Anschutz Medical Campus, Aurora"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth A. K.","family":"Rowley","sequence":"additional","affiliation":[{"name":"Westat, Bethesda, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adam","family":"Yates","sequence":"additional","affiliation":[{"name":"Westat, Bethesda, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Zhuang","sequence":"additional","affiliation":[{"name":"Westat, Bethesda, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Wilson","sequence":"additional","affiliation":[{"name":"Westat, Bethesda, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charlene E.","family":"McEvoy","sequence":"additional","affiliation":[{"name":"HealthPartners Institute, Minneapolis, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Inih J.","family":"Essien","sequence":"additional","affiliation":[{"name":"HealthPartners Institute, Minneapolis, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Omobosola O.","family":"Akinsete","sequence":"additional","affiliation":[{"name":"HealthPartners Institute, Minneapolis, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Allison L.","family":"Naleway","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Center for Health Research, Portland, Oregon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Padma","family":"Koppolu","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Center for Health Research, Portland, Oregon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ousseny","family":"Zerbo","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California Division of Research, Oakland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John R.","family":"Hansen","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California Division of Research, Oakland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen B.","family":"Jacobson","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California Division of Research, Oakland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lawrence","family":"Block","sequence":"additional","affiliation":[{"name":"Kaiser Permanente Vaccine Study Center, Kaiser Permanente Northern California Division of Research, Oakland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brian E.","family":"Dixon","sequence":"additional","affiliation":[{"name":"Center for Biomedical Informatics, Regenstrief Institute, Indianapolis, Indiana"},{"name":"Department of Health Policy and Management, Richard M. Fairbanks School of Public Health, Indiana University, Indianapolis"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Duszynski","sequence":"additional","affiliation":[{"name":"Center for Biomedical Informatics, Regenstrief Institute, Indianapolis, Indiana"},{"name":"Department of Epidemiology, Richard M. Fairbanks School of Public Health, Indiana University, Indianapolis"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Colin","family":"Rogerson","sequence":"additional","affiliation":[{"name":"Center for Biomedical Informatics, Regenstrief Institute, Indianapolis, Indiana"},{"name":"Department of Pediatrics, School of Medicine, Indiana University, Indianapolis"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michelle A.","family":"Barron","sequence":"additional","affiliation":[{"name":"School of Medicine, University of Colorado Anschutz Medical Campus, Aurora"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catia","family":"Chavez","sequence":"additional","affiliation":[{"name":"School of Medicine, University of Colorado Anschutz Medical Campus, Aurora"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Josephine","family":"Mak","sequence":"additional","affiliation":[{"name":"National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Allison Avrich","family":"Ciesla","sequence":"additional","affiliation":[{"name":"National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia"},{"name":"Eagle Health Analytics, San Antonio, Texas"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monica","family":"Godfrey","sequence":"additional","affiliation":[{"name":"National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amber","family":"Kautz","sequence":"additional","affiliation":[{"name":"National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia"},{"name":"General Dynamics Information Technology, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Morgan","family":"Najdowski","sequence":"additional","affiliation":[{"name":"National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia"},{"name":"Eagle Health Analytics, San Antonio, Texas"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ruth","family":"Link-Gelles","sequence":"additional","affiliation":[{"name":"National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia"},{"name":"US Public Health Service Commissioned Corps, Rockville, Maryland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jennifer","family":"DeCuir","sequence":"additional","affiliation":[{"name":"National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amanda B.","family":"Payne","sequence":"additional","affiliation":[{"name":"National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"10","published-online":{"date-parts":[[2026,6,23]]},"reference":[{"issue":"15","key":"zoi260704r7","doi-asserted-by":"publisher","first-page":"1355","DOI":"10.1056\/NEJMoa2110362","article-title":"Effectiveness of COVID-19 vaccines in ambulatory and inpatient care settings.","volume":"385","author":"Thompson","year":"2021","journal-title":"N Engl J Med"},{"issue":"51","key":"zoi260704r8","doi-asserted-by":"publisher","first-page":"7581","DOI":"10.1016\/j.vaccine.2023.11.025","article-title":"Impact of accounting for correlation between COVID-19 and influenza vaccination in a COVID-19 vaccine effectiveness evaluation using a test-negative design.","volume":"41","author":"Payne","year":"2023","journal-title":"Vaccine"},{"issue":"9596","key":"zoi260704r9","doi-asserted-by":"publisher","first-page":"1453","DOI":"10.1016\/S0140-6736(07)61602-X","article-title":"The strengthening the reporting of observational studies in epidemiology (STROBE) statement: guidelines for reporting observational studies.","volume":"370","author":"von Elm","year":"2007","journal-title":"Lancet"},{"issue":"6","key":"zoi260704r10","doi-asserted-by":"publisher","DOI":"10.1001\/jamanetworkopen.2025.17402","article-title":"Estimated 2023-2024 COVID-19 vaccine effectiveness in adults.","volume":"8","author":"Link-Gelles","year":"2025","journal-title":"JAMA Netw Open"},{"issue":"22","key":"zoi260704r11","doi-asserted-by":"publisher","first-page":"2221","DOI":"10.1056\/NEJMsa2514268","article-title":"Updated evidence for COVID-19, RSV, and influenza vaccines for 2025-2026.","volume":"393","author":"Scott","year":"2025","journal-title":"N Engl J Med"},{"issue":"2","key":"zoi260704r12","doi-asserted-by":"publisher","DOI":"10.1001\/jamanetworkopen.2025.57415","article-title":"Estimated effectiveness of 2024-2025 COVID-19 vaccination against severe COVID-19.","volume":"9","author":"Ma","year":"2026","journal-title":"JAMA Netw Open"},{"issue":"2","key":"zoi260704r13","doi-asserted-by":"publisher","first-page":"163","DOI":"10.1001\/jama.2024.5633","article-title":"Test-negative study designs for evaluating vaccine effectiveness.","volume":"332","author":"Dean","year":"2024","journal-title":"JAMA"},{"issue":"7","key":"zoi260704r15","doi-asserted-by":"publisher","first-page":"e374","DOI":"10.1016\/S1473-3099(25)00308-1","article-title":"Antigenic and virological characteristics of SARS-CoV-2 variants BA.3.2, XFG, and NB.1.8.1.","volume":"25","author":"Guo","year":"2025","journal-title":"Lancet Infect Dis"},{"issue":"10","key":"zoi260704r16","doi-asserted-by":"publisher","first-page":"130","DOI":"10.15585\/mmwr.mm7510a1","article-title":"Early detection and surveillance of the SARS-CoV-2 variant BA.3.2\u2014worldwide, November 2024-February 2026.","volume":"75","author":"Shakya","year":"2026","journal-title":"MMWR Morb Mortal Wkly Rep"},{"issue":"1","key":"zoi260704r17","doi-asserted-by":"publisher","first-page":"1008","DOI":"10.1038\/s41467-024-44973-1","article-title":"Risk of SARS-CoV-2 reinfection during multiple Omicron variant waves in the UK general population.","volume":"15","author":"Wei","year":"2024","journal-title":"Nat Commun"},{"key":"zoi260704r1","unstructured":"Centers for Disease Control and Prevention. Preliminary estimates of COVID-19 burden. Published February 6, 2026. Accessed March 13, 2026. https:\/\/www.cdc.gov\/covid\/php\/surveillance\/burden-estimates.html"},{"key":"zoi260704r2","unstructured":"Centers for Disease Control and Prevention. Coronavirus disease 2019 (COVID-19) hospitalization surveillance network (COVID-NET). Published January 30, 2026. Accessed March 13, 2026. https:\/\/www.cdc.gov\/covid\/php\/covid-net\/index.html"},{"key":"zoi260704r3","unstructured":"US Food and Drug Administration. COVID-19 vaccines (2025-2026 formula) for use in the United States beginning in fall 2025. Updated May 22, 2025. Accessed March 13, 2026. https:\/\/www.fda.gov\/vaccines-blood-biologics\/industry-biologics\/covid-19-vaccines-2025-2026-formula-use-united-states-beginning-fall-2025"},{"key":"zoi260704r4","unstructured":"Center for Biologics Evaluation and Research. Supplement approval: STN BL 125752\/305. US Food and Drug Administration. Published August 27, 2025. Accessed June 3, 2026. https:\/\/www.fda.gov\/media\/188448\/download?attachment"},{"key":"zoi260704r5","unstructured":"Center for Biologics Evaluation and Research. Supplement approval PMR fulfilled: STN BL 125742\/656. U.S. Food and Drug Administration. Published August 27, 2025. Accessed June 3, 2026. https:\/\/www.fda.gov\/media\/188439\/download?attachment"},{"key":"zoi260704r6","unstructured":"Center for Biologics Evaluation and Research. Supplement approval STN BL 125817\/6. US Food and Drug Administration. Published August 27, 2025. Accessed June 3, 2026. https:\/\/www.fda.gov\/media\/188446\/download?attachment"},{"key":"zoi260704r14","unstructured":"Centers for Disease Control and Prevention. Variants and genomic surveillance. Published August 28, 2025. Accessed March 13, 2026. https:\/\/www.cdc.gov\/covid\/php\/variants\/variants-and-genomic-surveillance.html"},{"key":"zoi260704r18","unstructured":"Centers for Disease Control and Prevention. COVID-19 national wastewater data. Updated May 29, 2026. Accessed June 3, 2026. https:\/\/www.cdc.gov\/nwss\/rv\/COVID19-national-data.html"},{"key":"zoi260704r19","unstructured":"Centers for Disease Control and Prevention. COVID-19 vaccination coverage and intent for vaccination, adults 18 years and older, United States. Published March 4, 2026. Accessed March 13, 2026. https:\/\/www.cdc.gov\/covidvaxview\/weekly-dashboard\/adult-vaccination-coverage.html"}],"container-title":["JAMA Network Open"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/jamanetwork.com\/journals\/jamanetworkopen\/articlepdf\/2850668\/wiegand_2026_oi_260704_1781565298.92194.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T16:30:41Z","timestamp":1782232241000},"score":1,"resource":{"primary":{"URL":"https:\/\/jamanetwork.com\/journals\/jamanetworkopen\/fullarticle\/2850668"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,23]]},"references-count":19,"journal-issue":{"issue":"6","published-print":{"date-parts":[[2026,6,1]]}},"URL":"https:\/\/doi.org\/10.1001\/jamanetworkopen.2026.25152","relation":{},"ISSN":["2574-3805"],"issn-type":[{"value":"2574-3805","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,23]]}}}