{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,21]],"date-time":"2026-03-21T07:54:32Z","timestamp":1774079672629,"version":"3.50.1"},"reference-count":19,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2023,9,5]],"date-time":"2023-09-05T00:00:00Z","timestamp":1693872000000},"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: Viruses are the major cause of acute respiratory infections in children, causing important morbimortality. Before the COVID-19 pandemic, in temperate regions, respiratory viruses displayed a typical seasonality in transmission. A disruption in this pattern was observed in several countries during the pandemic, with low prevalence during the typical season, and an interseasonal rise. We evaluated the effects of the COVID-19 pandemic in the epidemiology of non-COVID viral respiratory infections in children, in a tertiary care hospital in Portugal. Methods: Between March 2020 and August 2022, nasopharyngeal samples from children with respiratory symptoms in the Emergency Department (ED) and the Pediatric Ward were tested for RSV, influenza and other respiratory viruses, by real-time reverse transcriptase PCR (RT-PCR). Results: A seasonal variation was observed from 2018 to 2020, with prevalence increasing in winter (mainly RSV and influenza). In the winter of 2020\/21, when measures to mitigate SARS-CoV-2 transmission were stricter, there was a disruption of the seasonal pattern, with unusually low numbers. In the summer of 2021, when measures were being relaxed, there was an atypical rise. In June 2021, RSV was first detected and peaked in October. Influenza (Influenza A H3) was detected for the first time in February 2022, peaking in March\/April. Conclusions: These findings show a disruption of the seasonality of viral respiratory infections in children during the pandemic, with a virtual elimination during the months of usually higher prevalence, and a subsequent out-of-season increase, coinciding with variations in the measures implemented to control the SARS-CoV-2 transmission, and confirming their efficacy.<\/jats:p>","DOI":"10.3390\/v15091880","type":"journal-article","created":{"date-parts":[[2023,9,5]],"date-time":"2023-09-05T09:59:31Z","timestamp":1693907971000},"page":"1880","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Epidemiological Changes in Respiratory Viral Infections in Children: The Influence of the COVID-19 Pandemic"],"prefix":"10.3390","volume":"15","author":[{"given":"Teresa","family":"Almeida","sequence":"first","affiliation":[{"name":"Department of Clinical Pathology, S\u00e3o Jo\u00e3o Hospital University Center, 4200-319 Porto, Portugal"}]},{"given":"Jo\u00e3o Tiago","family":"Guimar\u00e3es","sequence":"additional","affiliation":[{"name":"Department of Clinical Pathology, S\u00e3o Jo\u00e3o Hospital University Center, 4200-319 Porto, Portugal"},{"name":"Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal"},{"name":"EPIUnit\u2014Institute of Public Health, University of Porto, 4050-600 Porto, Portugal"},{"name":"Laboratory for Integrative and Translational Research in Population Health (ITR), 4050-600 Porto, Portugal"}]},{"given":"Sandra","family":"Rebelo","sequence":"additional","affiliation":[{"name":"Department of Clinical Pathology, S\u00e3o Jo\u00e3o Hospital University Center, 4200-319 Porto, Portugal"},{"name":"Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal"},{"name":"Institute for Research and Innovation in Health (i3S Consortium), University of Porto, 4200-135 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"469","DOI":"10.1002\/ppul.10344","article-title":"Global burden of acute respiratory infections in children: Implications for interventions","volume":"36","author":"Mulholland","year":"2003","journal-title":"Pediatr. Pulmonol."},{"key":"ref_2","unstructured":"Calvo, C., Garcia, M., Casas, I., and Perez Bre\u00f1a, P. (2011). Protocolos Diagn\u00f3stico-Terap\u00e9uticos de la AEP: Infectolog\u00eda Pedi\u00e1trica, AEP. (In Spanish)."},{"key":"ref_3","unstructured":"World Health Organization (WHO) (2020, March 11). WHO Director-General\u2019s Opening Remarks at the Media Briefing on COVID-19. Available online: https:\/\/www.who.int\/dg\/speeches\/detail\/who-director-general-s-opening-remarks-at-the-media-briefing-on-covid-19---11-march-2020."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1146\/annurev-virology-012420-022445","article-title":"Seasonality of Respiratory Viral Infections","volume":"7","author":"Moriyama","year":"2020","journal-title":"Annu. Rev. Virol."},{"key":"ref_5","first-page":"e2020032","article-title":"Coronavirus infections in children: From SARS and MERS to COVID-19, a narrative review of epidemiological and clinical features","volume":"91","author":"Iannarella","year":"2020","journal-title":"Acta Biomed."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"e2021052089","DOI":"10.1542\/peds.2021-052089","article-title":"Delayed Seasonal RSV Surge Observed During the COVID-19 Pandemic","volume":"148","author":"Agha","year":"2021","journal-title":"Pediatrics"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"ciaa1906","DOI":"10.1093\/cid\/ciaa1906","article-title":"The Interseasonal Resurgence of Respiratory Syncytial Virus in Australian Children Following the Reduction of Coronavirus Disease 2019-Related Public Health Measures","volume":"73","author":"Foley","year":"2021","journal-title":"Clin. Infect. Dis."},{"key":"ref_8","first-page":"1560","article-title":"Low levels of respiratory syncytial virus activity in Europe during the 2020\/21 season: What can we expect in the coming summer and autumn\/winter?","volume":"26","author":"Meijer","year":"2021","journal-title":"Eurosurveillance"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1969","DOI":"10.1007\/s00431-021-03968-6","article-title":"Bronchiolitis in COVID-19 times: A nearly absent disease?","volume":"180","author":"Poschet","year":"2021","journal-title":"Eur. J. Pediatr."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1560","DOI":"10.2807\/1560-7917.ES.2021.26.29.2100630","article-title":"Characteristics of the delayed respiratory syncytial virus epidemic, 2020\/2021, Rh\u00f4ne Loire, France","volume":"26","author":"Casalegno","year":"2021","journal-title":"Eurosurveillance"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2199","DOI":"10.1093\/cid\/ciaa1475","article-title":"Impact of coronavirus disease 2019 public health measures on detections of influenza and respiratory syncytial virus in children during the 2020 Australian winter","volume":"72","author":"Yeoh","year":"2021","journal-title":"Clin. Infect. Dis."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"e42","DOI":"10.1016\/S2352-4642(20)30307-2","article-title":"COVID-19 public health measures and respiratory syncytial virus","volume":"4","author":"Britton","year":"2020","journal-title":"Lancet Child Adolesc. Health"},{"key":"ref_13","first-page":"2017","article-title":"Delayed respiratory syncytial virus epidemic in children after relaxation of COVID-19 physical distancing measures, Ashdod, Israel, 2021","volume":"26","author":"Yeshayahu","year":"2021","journal-title":"Eurosurveillance"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"3669","DOI":"10.1002\/ppul.25644","article-title":"Impact of COVID-19 social distancing on viral infection in France: A delayed outbreak of RSV","volume":"56","author":"Delestrain","year":"2021","journal-title":"Pediatr. Pulmonol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"408","DOI":"10.1002\/jmv.25674","article-title":"Recent advances in the detection of respiratory virus infection in humans","volume":"92","author":"Zhang","year":"2020","journal-title":"J. Med. Virol."},{"key":"ref_16","unstructured":"Cepheid (2021, December 20). Xpert\u00ae Xpress Flu\/RSV. Available online: https:\/\/www.cepheid.com\/pt\/tests\/Critical-Infectious-Diseases\/Xpert-Xpress-Flu-RSV."},{"key":"ref_17","unstructured":"Roche Diagnostics (2021, December 20). Cobas\u00ae Influenza A\/B & RSV UC Test. Available online: https:\/\/diagnostics.roche.com\/global\/en\/products\/params\/Cobas-influenza-a-b-rsv-uc-test.html."},{"key":"ref_18","unstructured":"BioFire Diagnostics (2021, December 20). The BioFire\u00ae Respiratory 2.1 (RP2.1) Panel. Available online: https:\/\/www.biofiredx.com\/products\/the-filmarray-panels\/filmarrayrp\/."},{"key":"ref_19","unstructured":"Seegene (2021, December 20). Allplex\u2122 Respiratory Panel Assays. Available online: https:\/\/www.seegene.com\/assays\/allplex_respiratory_panel_assays."}],"container-title":["Viruses"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1999-4915\/15\/9\/1880\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:46:44Z","timestamp":1760129204000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1999-4915\/15\/9\/1880"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,9,5]]},"references-count":19,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2023,9]]}},"alternative-id":["v15091880"],"URL":"https:\/\/doi.org\/10.3390\/v15091880","relation":{},"ISSN":["1999-4915"],"issn-type":[{"value":"1999-4915","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,9,5]]}}}