{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T18:23:51Z","timestamp":1785435831300,"version":"3.56.0"},"reference-count":34,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T00:00:00Z","timestamp":1778803200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"\u201cVictor Babe\u0219\u201d University of Medicine and Pharmacy, Timi\u0219oara"},{"id":[{"id":"https:\/\/ror.org\/00afdp487","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Evidence on hospitalised COVID-19 patients during the Omicron BA.5 wave from Eastern European, vaccine-heterogeneous cohorts remains limited. We conducted a retrospective single-centre cohort study of 395 consecutive adults admitted with laboratory-confirmed COVID-19 to a tertiary infectious-diseases unit in western Romania between 1 July and 31 October 2022. Median age was 72 years (IQR 65\u201381); 33.2% were unvaccinated, 42.8% had documented prior SARS-CoV-2 infection, and 41.3% were obese. Multivariable logistic regression identified independent predictors of in-hospital mortality and post-acute symptom burden. In-hospital mortality was 15.7% (62\/395). Vaccination was independently associated with lower mortality (adjusted odds ratio [aOR] 0.55, 95% CI 0.30\u20130.99; p = 0.048), as was each 1% increase in admission SpO2 (aOR 0.83, 95% CI 0.76\u20130.92; p &lt; 0.001), whereas COPD independently increased mortality risk (aOR 2.42, 95% CI 1.15\u20135.10; p = 0.020). Interleukin-6 was the most discriminating admission biomarker for in-hospital mortality (AUROC 0.70). Bloodstream bacterial co-infection, detected in 22.5% of patients tested on clinical suspicion, was dominated by gut-derived organisms with case-fatality \u226530%. At discharge, 90.1% reported persistent symptoms, most commonly cognitive (24.6%). Prior SARS-CoV-2 infection independently predicted post-acute symptom burden (aOR 2.96, 95% CI 1.75\u20135.01; p &lt; 0.001), with a specific cardiopulmonary signature. In this BA.5 cohort, vaccination remained protective; IL-6 was the most informative admission biomarker; bloodstream infections suggested gut translocation; and prior infection was an independent determinant of early post-acute symptom burden.<\/jats:p>","DOI":"10.3390\/microorganisms14051124","type":"journal-article","created":{"date-parts":[[2026,5,15]],"date-time":"2026-05-15T08:50:12Z","timestamp":1778835012000},"page":"1124","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Clinical Outcomes, Inflammatory Profile, Bacterial Co-Infections and Post-Acute Symptom Burden in Hospitalised COVID-19 Patients During the Omicron BA.5 Wave: A Single-Centre Cohort Study from Western Romania"],"prefix":"10.3390","volume":"14","author":[{"given":"Bogdan Adrian","family":"Manta","sequence":"first","affiliation":[{"name":"Division of Clinical Practical Skills, Faculty of Medicine, \u201cVictor Babe\u0219\u201d University of Medicine and Pharmacy Timi\u0219oara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-4951-1702","authenticated-orcid":false,"given":"Diana-Maria","family":"Mateescu","sequence":"additional","affiliation":[{"name":"Doctoral School, Department of General Medicine, \u201cVictor Babe\u0219\u201d University of Medicine and Pharmacy Timi\u0219oara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3536-6099","authenticated-orcid":false,"given":"Stela","family":"Iurciuc","sequence":"additional","affiliation":[{"name":"Cardiology Department, \u201cVictor Babe\u0219\u201d University of Medicine and Pharmacy Timi\u0219oara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cris Virgiliu","family":"Precup","sequence":"additional","affiliation":[{"name":"Department of Life Sciences, \u201cVasile Goldis\u201d Western University of Arad, 310414 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7573-3714","authenticated-orcid":false,"given":"Camelia Corina","family":"Pescaru","sequence":"additional","affiliation":[{"name":"Center for Research and Innovation in Personalized Medicine of Respiratory Diseases (CRIPMRD), \u201cVictor Babe\u0219\u201d Pneumology University Clinic, University of Medicine and Pharmacy Timi\u0219oara, Eftimie Murgu Square 2, 300041 Timisoara, Romania"},{"name":"Pulmonary Rehabilitation Center, Clinical Hospital of Infectious Diseases and Pulmonology, \u201cDr. Victor Babe\u0219\u201d Timi\u0219oara, Gheorghe Adam Street, No. 13, 300310 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alina Andreea","family":"Tischer","sequence":"additional","affiliation":[{"name":"Ear-Nose-Throat Department, \u201cVictor Babes\u201d University of Medicine and Pharmacy Timisoara, 300041 Timisoara, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,15]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2024). 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