{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,22]],"date-time":"2026-01-22T01:36:47Z","timestamp":1769045807037,"version":"3.49.0"},"reference-count":51,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T00:00:00Z","timestamp":1768953600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Background: Viral respiratory tract infections (RTIs) frequently lead to emergency department (ED) presentations and hospital admissions, particularly among older adults and individuals with underlying health conditions. Identifying patients at increased risk for hospitalization is essential for optimizing triage and resource allocation. This study aimed to determine independent demographic, clinical, and virological predictors of hospital admission among adults presenting with confirmed viral RTIs. Methods: A retrospective cohort study was conducted at a tertiary hospital between September 2022 and May 2024. Adult patients with molecularly confirmed viral RTIs were included. Demographic, clinical, and microbiological data were extracted from electronic medical records. Predictors of admission were assessed using univariate and multivariate logistic regression. Results: Among 311 patients, 147 (47.3%) required hospitalization. Hospitalized patients were significantly older and more likely to present with fever, cough, tachypnea, dyspnea, chest pain, comorbidities, and lower or mixed respiratory tract infections (all p &lt; 0.001). In multivariate analysis, older age, fever, cough, and lower or mixed RTIs were strong independent predictors of admission. Several viral pathogens, including human rhinovirus, non\u2013SARS-CoV-2 coronaviruses, influenza A, and parainfluenza virus, were associated with reduced odds of hospitalization. Conclusions: Age, comorbidity burden, and lower respiratory tract involvement are key determinants of hospitalization in viral RTIs. Integrating clinical and virological data may improve risk stratification and guide ED triage during seasonal and emerging respiratory virus activity.<\/jats:p>","DOI":"10.3390\/v18010135","type":"journal-article","created":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T11:11:17Z","timestamp":1768993877000},"page":"135","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Clinical, Demographic, and Virological Predictors of Hospital Admission in Patients with Acute Viral Respiratory Infections: A Retrospective Observational Study"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4289-9494","authenticated-orcid":false,"given":"Karolina","family":"Akinosoglou","sequence":"first","affiliation":[{"name":"Department of Medicine, University of Patras, Rio, 26504 Patra, Greece"},{"name":"Department of Internal Medicine, University General Hospital of Patras, Rio, 26504 Patras, Greece"},{"name":"Division of Infectious Diseases, Department of Internal Medicine, University General Hospital of Patras, Rio, 26504 Patras, Greece"},{"name":"School of Science and Technology, Hellenic Open University, 26335 Patras, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nikolaos","family":"Theofanis","sequence":"additional","affiliation":[{"name":"School of Science and Technology, Hellenic Open University, 26335 Patras, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Konstantinos","family":"Asimos","sequence":"additional","affiliation":[{"name":"Metropolitan General Hospital of Athens, 15562 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michail","family":"Michailidis","sequence":"additional","affiliation":[{"name":"Metropolitan General Hospital of Athens, 15562 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Despoina","family":"Papageorgiou","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Patras, Rio, 26504 Patra, Greece"},{"name":"Department of Internal Medicine, University General Hospital of Patras, Rio, 26504 Patras, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eleni","family":"Polyzou","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Patras, Rio, 26504 Patra, Greece"},{"name":"Department of Internal Medicine, University General Hospital of Patras, Rio, 26504 Patras, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Charalambos","family":"Gogos","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Patras, Rio, 26504 Patra, Greece"},{"name":"Metropolitan General Hospital of Athens, 15562 Athens, Greece"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,21]]},"reference":[{"key":"ref_1","unstructured":"(2024). 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