{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T05:15:58Z","timestamp":1780636558514,"version":"3.54.1"},"reference-count":26,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T00:00:00Z","timestamp":1760054400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Infectious Disease Reports"],"abstract":"<jats:p>Background\/Objectives: Influenza continues to cause high morbidity and mortality rates worldwide, inflicting a major burden on the public health system. There is little data available on the 2024\u20132025 seasonal outbreak. Moreover, biomarkers for rapidly identifying subjects at higher risk for severe forms are needed. Methods: We retrospectively collected hospitalization data for influenza in Cannes, France, during the 2024\u20132025 seasonal outbreak. Severe forms were defined as cases either requiring admission to the Intensive Care Unit (ICU) or resulting in death. They were compared to uncomplicated forms. Main demographic, clinical, radiological, and laboratory characteristics were collected for each patient. Results: From October 2024 to May 2025, 59 patients were admitted to either the Infectious Diseases Department or the ICU (56% male, age 72 years, 27% vaccinated, influenza type A 93%, symptom duration 3.5 days prior to hospitalization, 31% admissions to ICU, 14% deaths). Vaccination status did not differ between severe and uncomplicated forms. In the univariate analysis, severe forms had higher neutrophil\/lymphocyte and platelet\/lymphocyte ratios upon admission and included more cases of acute hepatitis, pneumonia, and oseltamivir use than uncomplicated forms. A neutrophil\/lymphocyte ratio &gt; 15 was independently associated with severity (ORadj 8.79, 95% CI: 1.34\u201357.6, p = 0.023), with 40.9% sensitivity, 94.6% specificity, 81.8% positive predictive value, and 72.3% negative predictive value for predicting a severe form. Conclusions: The N\/L ratio was an easy-to-perform predictive marker for influenza severity during the 2024\u20132025 seasonal outbreak, warranting further prospective studies<\/jats:p>","DOI":"10.3390\/idr17050127","type":"journal-article","created":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T09:45:01Z","timestamp":1760089501000},"page":"127","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["The Neutrophil\/Lymphocyte Ratio Was Identified as a Marker of Severe Influenza During the 2024\u20132025 Outbreak in France"],"prefix":"10.3390","volume":"17","author":[{"given":"Matteo","family":"Vassallo","sequence":"first","affiliation":[{"name":"Department of Internal Medicine Infectious Diseases, Cannes Hospital, 06400 Cannes, France"},{"name":"UR2CA (URRIS), Universit\u00e9 C\u00f4te d\u2019Azur, 06000 Nice, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marion","family":"Derollez","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine Infectious Diseases, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marc-Hadrien","family":"Veaute","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine Infectious Diseases, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9851-2666","authenticated-orcid":false,"given":"Nicolas","family":"Clement","sequence":"additional","affiliation":[{"name":"Intensive Care Unit, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5670-1322","authenticated-orcid":false,"given":"Roxane","family":"Fabre","sequence":"additional","affiliation":[{"name":"Public Health Department, UR2CA-RESPECT, 06000 Nice, France"},{"name":"Pain Management Unit and InovPain FHU, 06000 Nice, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laurene","family":"Lotte","sequence":"additional","affiliation":[{"name":"Multipurpose Laboratory, Bacteriology and Virology Unit, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yanis","family":"Kouchit","sequence":"additional","affiliation":[{"name":"Intensive Care Unit, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabrina","family":"Manni","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine Infectious Diseases, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ursula","family":"Moracchini","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine Infectious Diseases, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elea","family":"Blanchouin","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine Infectious Diseases, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julie","family":"Better","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine Infectious Diseases, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ludivine","family":"Rerolle","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine Infectious Diseases, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6805-1267","authenticated-orcid":false,"given":"Raphael","family":"Chambon","sequence":"additional","affiliation":[{"name":"Intensive Care Unit, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pierre","family":"Alfonsi Bertrand","sequence":"additional","affiliation":[{"name":"Intensive Care Unit, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Baccialone","sequence":"additional","affiliation":[{"name":"Intensive Care Unit, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-0774-9039","authenticated-orcid":false,"given":"Jerome","family":"Lemoine","sequence":"additional","affiliation":[{"name":"Intensive Care Unit, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Audrey","family":"Sindt","sequence":"additional","affiliation":[{"name":"Multipurpose Laboratory, Bacteriology and Virology Unit, Cannes Hospital, 06400 Cannes, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2285-5638","authenticated-orcid":false,"given":"Pierre-Marie","family":"Bertrand","sequence":"additional","affiliation":[{"name":"Intensive Care Unit, Cannes Hospital, 06400 Cannes, France"},{"name":"Aix Marseille Univ, CNRS, EFS, ADES, 13007 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1157","DOI":"10.1016\/j.cmi.2025.04.002","article-title":"How to manage antivirals in critically ill patients with influenza?","volume":"31","author":"Bay","year":"2025","journal-title":"Clin. 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