{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T20:57:59Z","timestamp":1792097879948,"version":"4.4.0"},"reference-count":39,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,11]],"date-time":"2025-09-11T00:00:00Z","timestamp":1757548800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Next-Generation EU-MUR PNRR Extended Partnership Initiative on Emerging Infectious Diseases"},{"name":"Italian Ministry of Health with \u201cCurrent Research funds\u201d"},{"name":"ANIA foundation"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Background: Respiratory syncytial virus (RSV) is a leading cause of acute respiratory infections (ARIs) in children. However, the clinical impact of RSV co-infection with other respiratory viruses remains unclear. This study investigates the frequency and clinical outcomes of RSV infections in a large paediatric cohort. Methods: Paediatric patients with RSV-positive respiratory samples admitted to Bambino Ges\u00f9 Children\u2019s Hospital between January 2022 and April 2024 were analysed. Results: Within 17,259 respiratory samples from 9877 paediatric patients, 952 (9.6%) were RSV-positive. Among these, 637 patients with ARI were included. RSV affected the lower respiratory tract in 549 cases (86.2%) and the upper tract in 88 (13.8%) cases. RSV mono-infection was found in 286 (44.9%) patients, while 351 (55.1%) patients had co-infections. Mono-infections showed lower cycle-threshold (CT) than co-infections in both upper and lower tract (p-value:0.002 and 0.037, respectively). Pneumonia was associated with RSV co-infection (N = 48, 15.4%), whereas bronchiolitis was mostly seen in mono-infection (N = 196, 78.1%, p-value:0.002). Regression analysis showed an association between pneumonia and co-infection (AOR: 1.97 [1.06\u20133.64], p-value = 0.031), higher CT (AOR [95% CI]: 1.07 [1.02\u20131.11], p-value = 0.006) and older age (AOR [95% CI]: 1.48 [1.31\u20131.68], p-value &lt; 0.001), whereas bronchiolitis was associated with mono-infection, younger age and lower CT. Conclusions: This study highlights the role of RSV in paediatric disease and emphasises the importance of early diagnosis, personalised treatment and preventive strategies to improve outcomes and reduce the burden of disease.<\/jats:p>","DOI":"10.3390\/v17091236","type":"journal-article","created":{"date-parts":[[2025,9,11]],"date-time":"2025-09-11T15:10:46Z","timestamp":1757603446000},"page":"1236","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Viral Burden of Respiratory Syncytial Virus and Viral Coinfections as Factors Regulating Paediatric Disease Severity"],"prefix":"10.3390","volume":"17","author":[{"given":"Velia Chiara","family":"Di Maio","sequence":"first","affiliation":[{"name":"Microbiology and Diagnostic Immunology Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCSS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rossana","family":"Scutari","sequence":"additional","affiliation":[{"name":"Multimodal Laboratory Research Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCCS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martina","family":"Mastropaolo","sequence":"additional","affiliation":[{"name":"Multimodal Laboratory Research Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCCS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5618-1523","authenticated-orcid":false,"given":"Luna","family":"Colagrossi","sequence":"additional","affiliation":[{"name":"Microbiology and Diagnostic Immunology Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCSS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4782-8158","authenticated-orcid":false,"given":"Giulia","family":"Linardos","sequence":"additional","affiliation":[{"name":"Microbiology and Diagnostic Immunology Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCSS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4933-4242","authenticated-orcid":false,"given":"Luana","family":"Coltella","sequence":"additional","affiliation":[{"name":"Microbiology and Diagnostic Immunology Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCSS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefania","family":"Ranno","sequence":"additional","affiliation":[{"name":"Microbiology and Diagnostic Immunology Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCSS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eugenia","family":"Galeno","sequence":"additional","affiliation":[{"name":"Microbiology and Diagnostic Immunology Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCSS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mara","family":"Pisani","sequence":"additional","affiliation":[{"name":"Paediatrics Clinical Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCCS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1164-5563","authenticated-orcid":false,"given":"Anna Chiara","family":"Vittucci","sequence":"additional","affiliation":[{"name":"Paediatrics Clinical Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCCS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sebastian","family":"Cristaldi","sequence":"additional","affiliation":[{"name":"Paediatrics Clinical Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCCS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Massimiliano","family":"Raponi","sequence":"additional","affiliation":[{"name":"Medical Direction, Bambino Ges\u00f9 Children\u2019s Hospital, IRCCS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9120-0424","authenticated-orcid":false,"given":"Alberto","family":"Villani","sequence":"additional","affiliation":[{"name":"Paediatrics Clinical Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCCS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6178-5460","authenticated-orcid":false,"given":"Cristina","family":"Russo","sequence":"additional","affiliation":[{"name":"Microbiology and Diagnostic Immunology Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCSS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlo Federico","family":"Perno","sequence":"additional","affiliation":[{"name":"Microbiology and Diagnostic Immunology Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCSS, 00165 Rome, Italy"},{"name":"Multimodal Laboratory Research Unit, Bambino Ges\u00f9 Children\u2019s Hospital, IRCCS, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,11]]},"reference":[{"key":"ref_1","first-page":"010408","article-title":"Aetiological role of common respiratory viruses in acute lower respiratory infections in children under five years: A systematic review and meta-analysis","volume":"5","author":"Shi","year":"2015","journal-title":"J. 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