{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T06:10:17Z","timestamp":1784182217532,"version":"3.55.0"},"reference-count":39,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T00:00:00Z","timestamp":1784160000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000005","name":"U.S. Department of Defense","doi-asserted-by":"publisher","award":["HU0001190002"],"award-info":[{"award-number":["HU0001190002"]}],"id":[{"id":"10.13039\/100000005","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["Y1-Al-5072"],"award-info":[{"award-number":["Y1-Al-5072"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Public Health"],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Obesity prevalence is rising globally and associated with increased influenza mortality. The relationship between obesity and influenza-like-illness (ILI) incidence and symptom severity is less clear.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Materials and methods<\/jats:title>\n                    <jats:p>US Military Health System (MHS) beneficiaries enrolled in a randomized influenza vaccine trial received one of three influenza vaccines and were followed for ILI via weekly surveys throughout one influenza season. Participants were pooled across vaccine arms into a prospective cohort. We compared ILI risk and ILI symptom severity (Flu-PRO) across body mass index (BMI) categories using multivariable regression models.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Among the 8,334 participants with &amp;gt;50% response rates to weekly ILI surveys, 42% had an overweight-range BMI and 24% had an obesity-range BMI. The median age was 36.2, and 86% had no baseline comorbidities. Over one quarter of the participants (27%) reported at least one ILI during follow-up, with a median duration of 11 days. Participants with an overweight and obesity-range BMI were more likely to report ILIs [adjusted incidence rate ratio (aIRR) 1.18 (95% confidence interval (CI): 1.05\u20131.33) and 1.59 (95% CI: 1.37\u20131.84), respectively]. Participants with obesity also had higher risks of reporting moderate-to-severe symptoms in four Flu-PRO domains: gastrointestinal, respiratory, systemic, and throat [adjusted risk ratio (aRR) of 1.64 (95% CI: 1.01\u20132.70), 1.33 (95% CI: 1.05\u20131.67), 1.32 (95% CI: 1.06\u20131.63), and 1.20 (95% CI 1.02\u20131.40) respectively].<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Higher BMI was associated with ILI incidence and severity. These findings prompt further research into optimal strategies to reduce the impact of ILI in MHS settings and the general population.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fpubh.2026.1874186","type":"journal-article","created":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T05:40:01Z","timestamp":1784180401000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Assessing the relationship between body mass index and influenza-like illness risk and symptom severity among military health system beneficiaries vaccinated against influenza: a pooled prospective cohort study from a randomized trial"],"prefix":"10.3389","volume":"14","author":[{"given":"Mofan","family":"Gu","sequence":"first","affiliation":[{"name":"Infectious Disease Clinical Research Program, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences","place":["Bethesda, MD, United States"]},{"name":"The Henry M. 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