{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T18:00:28Z","timestamp":1781632828160,"version":"3.54.5"},"reference-count":29,"publisher":"Springer Science and Business Media LLC","issue":"4","license":[{"start":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T00:00:00Z","timestamp":1768608000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T00:00:00Z","timestamp":1768608000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100007606","name":"Aarhus University Hospital","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100007606","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Eur J Clin Microbiol Infect Dis"],"published-print":{"date-parts":[[2026,4]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>Patients admitted with viral respiratory tract infections are at risk ofbacterial co-infections that may exacerbate disease severity. Detection of atypical bacteria requires specific laboratory diagnostic modality and specific antibiotics.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In this retrospective regionwide cohort study we included all patients admitted to a hospital in the Central Denmark Region with COVID-19, influenza A, influenza B, or Respiratory Syncytial Virus (RSV) from February 2019 to February 2024. Firstly, we investigated the number of patients testing positive for atypical bacterial co-infection. Secondly, we evaluated associations with diagnostic testing for these atypical bacteria, and the use and associations with administration of empirical treatment with clarithromycin.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      During the study period a total of 19,651 patients were admitted with one of the viral respiratory tract infections. Only 21 patients tested positive for atypical bacterial co-infection, corresponding to 0.1% of those tested (\n                      <jats:italic>n<\/jats:italic>\n                      \u2009=\u20092,369). Empirical clarithromycin was administered to 859 (4.4%) patients. Still 17 out of the 21 patients (81.0%) with atypical bacterial co-infection did not receive clarithromycin before the result of diagnostic test was available.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Our findings do not support routine testing for atypical bacterial co-infection and use of empirical treatment for atypical pneumonia in this population.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s10096-026-05405-8","type":"journal-article","created":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T13:41:25Z","timestamp":1768657285000},"page":"1157-1165","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Implications of empirical testing and treatment for atypical bacteria in patients hospitalized with COVID, influenza, or RSV: a retrospective observational cohort study"],"prefix":"10.1007","volume":"45","author":[{"given":"Bo Langhoff","family":"H\u00f8nge","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jacob","family":"Redder","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas","family":"Greve","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lars Skov","family":"Dalgaard","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anita Rath","family":"S\u00f8rensen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lotte","family":"Ebdrup","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rajesh","family":"Mohey","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Britta","family":"Tarp","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mette","family":"Holm","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lars","family":"\u00d8stergaard","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Merete","family":"Storgaard","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,1,17]]},"reference":[{"key":"5405_CR1","doi-asserted-by":"publisher","first-page":"822","DOI":"10.1016\/S2213-2600(24)00255-8","volume":"12","author":"JG Wildenbeest","year":"2024","unstructured":"Wildenbeest JG, Lowe DM, Standing JF, Butler CC (2024) Respiratory syncytial virus infections in adults: a narrative review. 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The authors declare that AI was not used for the writing of this article.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Disclosures"}},{"value":"BLH and JR had full access to data and are guarantors for the data.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Access to data"}}]}}