{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,27]],"date-time":"2026-01-27T23:18:33Z","timestamp":1769555913440,"version":"3.49.0"},"reference-count":24,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,8,12]],"date-time":"2022-08-12T00:00:00Z","timestamp":1660262400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Background: Since 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic (COVID-19) has caused millions of deaths worldwide and is the second most serious pandemic after the Spanish flu. Despite SARS-CoV-2 infection having a dominant effect on morbidity and life-threatening outcomes, the role of bacterial co-infection in patients with COVID-19 is poorly understood. The present study aimed to verify the existence of bacterial co-infections and their possible role as cofactors worsening COVID-19-related clinical manifestations. Methods: All patients with suspected SARS-CoV-infection, hospitalised in COVID-19 wards at the Sant\u2019Anna University Hospital of Ferrara, were retrospectively included in this single-centre study and their specific bacterial serologies were assessed. Univariate and logistic regression analyses were performed. Results: A total of 1204 individual records were retrieved. Among them, 959 were excluded because of a negative nasopharyngeal swab or missing data; of the eligible 245 patients, 51 were co-infected. Compared to patients with SARS-CoV-2 infection alone, those with Chlamydia pneumoniae or Mycoplasma pneumoniae co-infections had worse respiratory\/radiological features and more intensive care unit admissions. However, the co-infection did not result in a higher mortality rate. Conclusions: The present study, comparing clinical, laboratory and radiological findings between patients with COVID-19 vs. those with co-infections (C. pneumoniae or M. pneumoniae) showed that, on admission, these features were worse in co-infected patients, although the mortality rate did not differ between the two groups.<\/jats:p>","DOI":"10.3390\/microorganisms10081636","type":"journal-article","created":{"date-parts":[[2022,8,15]],"date-time":"2022-08-15T03:33:20Z","timestamp":1660534400000},"page":"1636","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Role of Intracellular Pulmonary Pathogens during SARS-CoV-2 Infection in the First Pandemic Wave of COVID-19: Clinical and Prognostic Significance in a Case Series of 1200 Patients"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5841-8555","authenticated-orcid":false,"given":"Matteo","family":"Guarino","sequence":"first","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4365-2968","authenticated-orcid":false,"given":"Benedetta","family":"Perna","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9093-3020","authenticated-orcid":false,"given":"Francesca","family":"Cuoghi","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michele Domenico","family":"Spampinato","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alice Eleonora","family":"Cesaro","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2898-4323","authenticated-orcid":false,"given":"Francesca","family":"Manza","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Adriana","family":"Pretula","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anastasio","family":"Grilli","sequence":"additional","affiliation":[{"name":"Infectious and Dermatology Diseases, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Martina","family":"Maritati","sequence":"additional","affiliation":[{"name":"Infectious and Dermatology Diseases, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4244-4529","authenticated-orcid":false,"given":"Giacomo","family":"Caio","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8191-6042","authenticated-orcid":false,"given":"Aldo","family":"Carnevale","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria Elena","family":"Flacco","sequence":"additional","affiliation":[{"name":"Department of Environmental and Preventive Sciences, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0867-5873","authenticated-orcid":false,"given":"Roberto","family":"De Giorgio","sequence":"additional","affiliation":[{"name":"Department of Translational Medicine, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8809-6470","authenticated-orcid":false,"given":"Carlo","family":"Contini","sequence":"additional","affiliation":[{"name":"Infectious and Dermatology Diseases, St. Anna University Hospital of Ferrara, University of Ferrara, 44124 Ferrara, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"727","DOI":"10.1056\/NEJMoa2001017","article-title":"Novel Coronavirus from Patients with Pneumonia in China, 2019. 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