{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T14:37:06Z","timestamp":1787582226307,"version":"build-2736575974"},"reference-count":39,"publisher":"Oxford University Press (OUP)","issue":"8","funder":[{"DOI":"10.13039\/100000738","name":"US Department of Veterans Affairs","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100000738","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100011556","name":"CSP","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100011556","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100012737","name":"Department of Health and Human Services","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100012737","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100024247","name":"DHHS","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100024247","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100012399","name":"Biomedical Advanced Research and Development Authority","doi-asserted-by":"publisher","award":["AAI21050"],"award-info":[{"award-number":["AAI21050"]}],"id":[{"id":"10.13039\/100012399","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000038","name":"US Food and Drug Administration","doi-asserted-by":"publisher","award":["75F40121S30013"],"award-info":[{"award-number":["75F40121S30013"]}],"id":[{"id":"10.13039\/100000038","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The effectiveness of oseltamivir for the treatment of nonsevere influenza in preventing progression to severe illness is uncertain.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In a target trial emulation of veterans who presented to emergency departments in the Veterans Health Administration (VHA) and tested positive for influenza between 1 October 2022\u201331 January 2023, or 1 December 2023\u201331 March 2024, we compared treatment with oseltamivir versus no antiviral treatment within 6\u2005hours of a positive influenza test. Following inverse probability of treatment weighting, we calculated cumulative incidence, risk differences (RDs), and risk ratios (RR) for hospitalization and intensive care unit (ICU) admission at 10 days and death at 30 days.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among 28 920 veterans, 25 025 (87%) were male with median age 61 (45\u201372) years. Oseltamivir-treated patients had a lower risk of hospitalization (3.81% vs 6.96%; RD, \u22123.15% [95% confidence interval {CI}, \u22123.70% to \u22122.60%]; RR, 0.55 [CI, .49\u2013.61]) and ICU admission (0.65% vs 1.38%; RD, \u22120.73% [CI, \u2212.98% to \u2212.48%]; RR, 0.47 [CI, .35\u2013.62]) than untreated persons. The largest absolute risk reductions in hospitalization occurred in patients \u226565 years (RD, \u22125.21% [CI, \u22126.39% to \u22124.04%]) and among those prescribed treatment within 3\u2005hours of testing positive (RD, \u22125.77% [CI, \u22126.54% to \u22125.00%]). Overall incidence of death was similar between groups (RD, 0.10% [CI \u2212.07%\u2013.27%]).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Oseltamivir reduced the risk of hospitalization and ICU admission but not death. Substantial reductions in hospitalization risk were observed in older adults and patients prescribed treatment within 3\u2005hours of diagnosis.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ofid\/ofag464","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T11:38:21Z","timestamp":1785843501000},"source":"Crossref","is-referenced-by-count":0,"title":["Oseltamivir for Treatment of Influenza Among Outpatient Veterans: Target Trial Emulation"],"prefix":"10.1093","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4779-2688","authenticated-orcid":false,"given":"Lei","family":"Yan","sequence":"first","affiliation":[{"name":"Veterans Affairs Cooperative Studies Program Clinical Epidemiology Research Center, Veterans Affairs Connecticut Health Care System , West Haven, Connecticut ,","place":["USA"]},{"name":"Department of Biostatistics, Yale School of Public Health , New Haven, Connecticut ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuli","family":"Li","sequence":"additional","affiliation":[{"name":"Veterans Affairs Cooperative Studies Program Clinical Epidemiology Research Center, Veterans Affairs Connecticut Health Care System , West Haven, Connecticut ,","place":["USA"]},{"name":"Biomedical Informatics and Data Science, Yale School of Medicine , New Haven, Connecticut ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Vergun","sequence":"additional","affiliation":[{"name":"Veterans Affairs Portland Health Care System , Portland, Oregon ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2045-0872","authenticated-orcid":false,"given":"Nallakkandi","family":"Rajeevan","sequence":"additional","affiliation":[{"name":"Veterans Affairs Cooperative Studies Program Clinical Epidemiology Research Center, Veterans Affairs Connecticut Health Care System , West Haven, Connecticut ,","place":["USA"]},{"name":"Biomedical Informatics and Data Science, Yale School of Medicine , New Haven, Connecticut ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-7372-7727","authenticated-orcid":false,"given":"Kristin","family":"Berry","sequence":"additional","affiliation":[{"name":"Research and Development, Veterans Affairs Puget Sound Health Care System , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-4573-4617","authenticated-orcid":false,"given":"Pradeep","family":"Mutalik","sequence":"additional","affiliation":[{"name":"Veterans Affairs Cooperative Studies Program Clinical Epidemiology Research Center, Veterans Affairs Connecticut Health Care System , West Haven, Connecticut ,","place":["USA"]},{"name":"Biomedical Informatics and Data Science, Yale School of Medicine , New Haven, Connecticut ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen","family":"Anderson","sequence":"additional","affiliation":[{"name":"Veterans Affairs Cooperative Studies Program Clinical Epidemiology Research Center, Veterans Affairs Connecticut Health Care System , West Haven, Connecticut ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeanpaul","family":"Vales","sequence":"additional","affiliation":[{"name":"Veterans Affairs Cooperative Studies Program Clinical Epidemiology Research Center, Veterans Affairs Connecticut Health Care System , West Haven, Connecticut ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Denise M","family":"Hynes","sequence":"additional","affiliation":[{"name":"Veterans Affairs Portland Health Care System , Portland, Oregon ,","place":["USA"]},{"name":"Health Management and Policy, College of Health; Center for Quantitative Life Sciences, Oregon State University , Corvallis, Oregon ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0861-0850","authenticated-orcid":false,"given":"David P","family":"Bui","sequence":"additional","affiliation":[{"name":"Veterans Affairs Portland Health Care System , Portland, Oregon ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3176-6570","authenticated-orcid":false,"given":"Hung-Mo","family":"Lin","sequence":"additional","affiliation":[{"name":"Veterans Affairs Cooperative Studies Program Clinical Epidemiology Research Center, Veterans Affairs Connecticut Health Care System , West Haven, Connecticut ,","place":["USA"]},{"name":"Department of Biostatistics, Yale School of Public Health , New Haven, Connecticut ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuan","family":"Huang","sequence":"additional","affiliation":[{"name":"Veterans Affairs Cooperative Studies Program Clinical Epidemiology Research Center, Veterans Affairs Connecticut Health Care System , West Haven, Connecticut ,","place":["USA"]},{"name":"Department of Biostatistics, Yale School of Public Health , New Haven, Connecticut ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mihaela","family":"Aslan","sequence":"additional","affiliation":[{"name":"Veterans Affairs Cooperative Studies Program Clinical Epidemiology Research Center, Veterans Affairs Connecticut Health Care System , West Haven, Connecticut ,","place":["USA"]},{"name":"Department of Internal Medicine, Yale School of Medicine , New Haven, Connecticut ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1796-8977","authenticated-orcid":false,"given":"George N","family":"Ioannou","sequence":"additional","affiliation":[{"name":"Divisions of Gastroenterology, Veterans Affairs Puget Sound Health Care System and University of Washington , Seattle, Washington ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3229-5590","authenticated-orcid":false,"given":"Kristina L","family":"Bajema","sequence":"additional","affiliation":[{"name":"Veterans Affairs Portland Health Care System , Portland, Oregon ,","place":["USA"]},{"name":"Division of Infectious Diseases, Department of Medicine, Oregon Health and Sciences University , Portland, Oregon 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