{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T23:46:20Z","timestamp":1792107980292,"version":"4.4.0"},"reference-count":26,"publisher":"Springer Science and Business Media LLC","issue":"3","license":[{"start":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T00:00:00Z","timestamp":1768348800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T00:00:00Z","timestamp":1768348800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Pediatr Res"],"published-print":{"date-parts":[[2026,8]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The COVID-19 pandemic has altered the typical annual pattern of influenza. We aim to assess its impact on influenza outcomes, especially on mortality, cardiovascular, and non-cardiovascular complications.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This study utilized discharge records from the National Inpatient Sample (NIS) for 2019 and 2022. We analyzed the data of hospitalized influenza patients (20 years and younger) using descriptive statistics and logistic regression models.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      29,270 influenza hospitalizations were identified in the pre-pandemic year and 29,860 in the post-mitigation year. The median age was 6 years (IQR: 2\u201312) in the post-mitigation year vs. 4 years (IQR: 1\u20139) in the pre-pandemic year,\n                      <jats:italic>P<\/jats:italic>\n                      \u2009&lt;\u20090.001. Mortality and major cardiovascular complications, including myocarditis and tachyarrhythmias, showed no differences. Respiratory failure was more common in post-mitigation (21.4% vs. 12.7%), with nearly twice the risk in adjusted models [aOR\u2009=\u20091.92 (1.68\u20132.19),\n                      <jats:italic>P<\/jats:italic>\n                      \u2009&lt;\u20090.001]. Invasive mechanical ventilation use decreased in the post-mitigation year by 30% [aOR\u2009=\u20090.7 (0.55\u20130.89),\n                      <jats:italic>P<\/jats:italic>\n                      \u2009=\u20090.004].\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Mortality and cardiovascular complications remained stable in pre- and post-mitigation year; however, post-pandemic influenza showed an increased risk of respiratory failure with a decreased invasive mechanical ventilation use. This suggests a shift in disease presentation and clinical management strategies in the post-mitigation period.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Impact<\/jats:title>\n                    <jats:p>\n                      <jats:list list-type=\"bullet\">\n                        <jats:list-item>\n                          <jats:p>Influenza\u2019s clinical profile in children has changed post-COVID, with increased respiratory failure and a shift to older affected age groups, while mortality and severe cardiovascular complications remain stable.<\/jats:p>\n                        <\/jats:list-item>\n                        <jats:list-item>\n                          <jats:p>This study is the first to systematically compare pediatric influenza outcomes, including all major complications and mortality, pre- and post-COVID-19, revealing specific shifts in disease presentation and demographics.<\/jats:p>\n                        <\/jats:list-item>\n                        <jats:list-item>\n                          <jats:p>Informs clinical vigilance, diagnostic strategies, and public health planning for pediatric influenza by highlighting shifts in hospitalization patterns and complications observed during the post-mitigation period.<\/jats:p>\n                        <\/jats:list-item>\n                        <jats:list-item>\n                          <jats:p>Findings support preparedness efforts recognizing temporal disruptions surrounding the pandemic.<\/jats:p>\n                        <\/jats:list-item>\n                      <\/jats:list>\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1038\/s41390-025-04759-7","type":"journal-article","created":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T18:26:34Z","timestamp":1768415194000},"page":"1353-1358","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Clinical outcomes of influenza in individuals aged \u226420 years before and after COVID-19: a national analysis of mortality and complications"],"prefix":"10.1038","volume":"100","author":[{"given":"Bishes","family":"Khanal","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sandhya J.","family":"Kadam","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sagya","family":"Khanal","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fu-Sheng","family":"Chou","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana C.","family":"Coll","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manish B.","family":"Malkar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anita J.","family":"Moon-Grady","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Laxmi V.","family":"Ghimire","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,1,14]]},"reference":[{"key":"4759_CR1","doi-asserted-by":"publisher","first-page":"3","DOI":"10.1038\/s41572-018-0002-y","volume":"4","author":"F Krammer","year":"2018","unstructured":"Krammer, F. et al. Influenza. Nat. Rev. Dis. Primers 4, 3 (2018).","journal-title":"Nat. Rev. Dis. Primers"},{"key":"4759_CR2","unstructured":"Centers for Disease Control and Prevention (CDC). Preliminary Estimated Flu Disease Burden 2024\u20132025 Flu Season. (https:\/\/www.cdc.gov\/flu-burden\/php\/data-vis\/2024-2025.html) (2024)."},{"key":"4759_CR3","unstructured":"World Health Organization. Influenza (seasonal), (https:\/\/www.who.int\/news-room\/fact-sheets\/detail\/influenza-(seasonal)) (2025)."},{"key":"4759_CR4","unstructured":"Centers for Disease Control and Prevention (CDC). About Estimated Flu Burden, (https:\/\/www.cdc.gov\/flu-burden\/php\/about\/index.html) (2024)."},{"key":"4759_CR5","first-page":"100132","volume":"7","author":"HE Groves","year":"2022","unstructured":"Groves, H. E. et al. The effect of the COVID-19 pandemic on influenza-related hospitalization, intensive care admission and mortality in children in Canada: A population-based study. Lancet Reg. Health Am. 7, 100132 (2022).","journal-title":"Lancet Reg. Health Am."},{"key":"4759_CR6","doi-asserted-by":"crossref","unstructured":"Adlhoch, C. et al. Very little influenza in the WHO European Region during the 2020\/21 season, weeks 40 2020 to 8 2021. Euro Surveill. 26, 2100221 (2021).","DOI":"10.2807\/1560-7917.ES.2021.26.11.2100221"},{"key":"4759_CR7","doi-asserted-by":"publisher","DOI":"10.1111\/irv.13178","volume":"17","author":"G Hoy","year":"2023","unstructured":"Hoy, G. et al. Increased influenza severity in children in the wake of SARS-CoV-2. Influenza Other Respi. Viruses 17, e13178 (2023).","journal-title":"Influenza Other Respi. Viruses"},{"key":"4759_CR8","doi-asserted-by":"crossref","unstructured":"Williams, T. C., Sinha, I., Barr, I. G. & Zambon, M. Transmission of paediatric respiratory syncytial virus and influenza in the wake of the COVID-19 pandemic. Euro Surveill. 26, 2100186 (2021).","DOI":"10.2807\/1560-7917.ES.2021.26.29.2100186"},{"key":"4759_CR9","doi-asserted-by":"publisher","first-page":"828","DOI":"10.1186\/s12887-024-05285-x","volume":"24","author":"F Lin","year":"2024","unstructured":"Lin, F., Liang, J.-L., Guan, Z.-X., Wu, M. & Yang, L.-Y. Hospitalized children with influenza A before, during and after COVID-19 pandemic: a retrospective cohort study. BMC Pediatr 24, 828 (2024).","journal-title":"BMC Pediatr"},{"key":"4759_CR10","unstructured":"Healthcare Cost and Utilization Project (HCUP). Agency for Healthcare Research and Quality (Rockville, MD). (https:\/\/www.hcup-us.ahrq.gov\/nisoverview.jsp) (2021)."},{"key":"4759_CR11","unstructured":"RStudio Team. RStudio: integrated development for R. Boston, MA: RStudio, Inc; (http:\/\/www.rstudio.com\/) (2016)."},{"key":"4759_CR12","doi-asserted-by":"publisher","first-page":"1108","DOI":"10.15585\/mmwr.mm7241a2","volume":"72","author":"EB White","year":"2023","unstructured":"White, E. B. et al. High influenza incidence and disease severity among children and adolescents aged <18 years - United States, 2022-23 season. MMWR Morb. Mortal. Wkly. Rep. 72, 1108\u20131114 (2023).","journal-title":"MMWR Morb. Mortal. Wkly. Rep."},{"key":"4759_CR13","unstructured":"Centers for Disease Control and Prevention (CDC). Pediatric Flu Deaths Top 100 this Season; Most Unvaccinated, (https:\/\/www.cdc.gov\/flu\/spotlights\/2022-2023\/pediatric-flu-deaths.htm#print) (2024)."},{"key":"4759_CR14","doi-asserted-by":"publisher","DOI":"10.1111\/irv.70078","volume":"19","author":"A Gentile","year":"2025","unstructured":"Gentile, A. et al. Comparative analysis of influenza epidemiology before and after the COVID-19 pandemic in Argentina (2018-2019 vs. 2022-2023). Influenza Other Respi. Viruses 19, e70078 (2025).","journal-title":"Influenza Other Respi. Viruses"},{"key":"4759_CR15","doi-asserted-by":"publisher","first-page":"69","DOI":"10.5603\/aa.99211","volume":"30","author":"MH Kalantar Neyestanaki","year":"2024","unstructured":"Kalantar Neyestanaki, M. H. & Kalantar Neyestanaki, M. Influenza and its cardiovascular complications: a comprehensive review. Acta Angiol 30, 69\u201378 (2024).","journal-title":"Acta Angiol"},{"key":"4759_CR16","doi-asserted-by":"publisher","first-page":"686","DOI":"10.1186\/s12872-024-04366-0","volume":"24","author":"S Khanal","year":"2024","unstructured":"Khanal, S., Khanal, B., Chou, F.-S., Moon-Grady, A. J. & Ghimire, L. V. Comparison of mortality and cardiovascular complications due to COVID-19, RSV, and influenza in hospitalized children and young adults. BMC Cardiovasc. Disord. 24, 686 (2024).","journal-title":"BMC Cardiovasc. Disord."},{"key":"4759_CR17","doi-asserted-by":"publisher","first-page":"P3858","DOI":"10.1093\/eurheartj\/eht309.P3858","volume":"34","author":"A Ukimura","year":"2013","unstructured":"Ukimura, A., Ooi, Y. & Kanzaki, Y. The need for increased awareness of influenza virus A-associated myocarditis in children during the pandemic season. Eur. Heart J. 34, P3858\u2013P3858 (2013).","journal-title":"Eur. Heart J."},{"key":"4759_CR18","doi-asserted-by":"publisher","first-page":"417","DOI":"10.1016\/j.jiph.2023.12.018","volume":"17","author":"S Puzelli","year":"2024","unstructured":"Puzelli, S. et al. Characterization of an influenza B virus isolated from a fatal case of myocarditis in a pediatric patient in Italy. J. Infect. Public Health 17, 417\u2013420 (2024).","journal-title":"J. Infect. Public Health"},{"key":"4759_CR19","doi-asserted-by":"publisher","DOI":"10.1186\/s13019-024-02997-0","volume":"19","author":"F Tian","year":"2024","unstructured":"Tian, F. et al. Fulminant myocarditis caused by influenza B virus in a male child: a case report and literature review. J. Cardiothorac. Surg. 19, 492 (2024).","journal-title":"J. Cardiothorac. Surg."},{"key":"4759_CR20","doi-asserted-by":"publisher","first-page":"128","DOI":"10.3389\/fped.2016.00128","volume":"4","author":"S Nye","year":"2016","unstructured":"Nye, S., Whitley, R. J. & Kong, M. Viral infection in the development and progression of pediatric acute respiratory distress syndrome. Front. Pediatr. 4, 128 (2016).","journal-title":"Front. Pediatr."},{"key":"4759_CR21","doi-asserted-by":"publisher","first-page":"1663","DOI":"10.1016\/S0140-6736(22)01277-6","volume":"400","author":"K Messacar","year":"2022","unstructured":"Messacar, K. et al. Preparing for uncertainty: endemic paediatric viral illnesses after COVID-19 pandemic disruption. Lancet 400, 1663\u20131665 (2022).","journal-title":"Lancet"},{"key":"4759_CR22","doi-asserted-by":"publisher","first-page":"102089","DOI":"10.1016\/j.eclinm.2023.102089","volume":"61","author":"B Abu-Raya","year":"2023","unstructured":"Abu-Raya, B., Vi\u00f1eta Paramo, M., Reicherz, F. & Lavoie, P. M. Why has the epidemiology of RSV changed during the COVID-19 pandemic? EClinicalMedicine 61, 102089 (2023).","journal-title":"EClinicalMedicine"},{"key":"4759_CR23","doi-asserted-by":"publisher","first-page":"185","DOI":"10.1016\/j.ijsu.2020.04.018","volume":"78","author":"M Nicola","year":"2020","unstructured":"Nicola, M. et al. The socio-economic implications of the coronavirus pandemic (COVID-19): A review. Int. J. Surg. 78, 185\u2013193 (2020).","journal-title":"Int. J. Surg."},{"key":"4759_CR24","doi-asserted-by":"publisher","first-page":"6063","DOI":"10.3390\/jcm11206063","volume":"11","author":"L Pasin","year":"2022","unstructured":"Pasin, L. et al. Outcomes of COVID-19 patients with severe hypoxemic acute respiratory failure: Non-invasive ventilation vs. Straight intubation-A propensity score-matched multicenter cohort study. J. Clin. Med. 11, 6063 (2022).","journal-title":"J. Clin. Med."},{"key":"4759_CR25","doi-asserted-by":"publisher","first-page":"1989","DOI":"10.1016\/j.jiph.2023.09.018","volume":"16","author":"K Bin Saleh","year":"2023","unstructured":"Bin Saleh, K. et al. Assessing the influence of COVID-19 on influenza prevalence: A multicenter time series study. J. Infect. Public Health 16, 1989\u20131993 (2023).","journal-title":"J. Infect. Public Health"},{"key":"4759_CR26","doi-asserted-by":"publisher","DOI":"10.1186\/s12889-024-19460-3","volume":"24","author":"W Jia","year":"2024","unstructured":"Jia, W. et al. Changes in the epidemiological characteristics of influenza in children in Zhengzhou, China, in the post-COVID-19 era. BMC Public Health 24, 1938 (2024).","journal-title":"BMC Public Health"}],"container-title":["Pediatric Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.nature.com\/articles\/s41390-025-04759-7.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.nature.com\/articles\/s41390-025-04759-7","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.nature.com\/articles\/s41390-025-04759-7.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T22:57:38Z","timestamp":1792105058000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.nature.com\/articles\/s41390-025-04759-7"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,14]]},"references-count":26,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2026,8]]}},"alternative-id":["4759"],"URL":"https:\/\/doi.org\/10.1038\/s41390-025-04759-7","relation":{},"ISSN":["0031-3998","1530-0447"],"issn-type":[{"value":"0031-3998","type":"print"},{"value":"1530-0447","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,14]]},"assertion":[{"value":"21 July 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"29 November 2025","order":2,"name":"revised","label":"Revised","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"22 December 2025","order":3,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"14 January 2026","order":4,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.","order":1,"name":"Ethics","label":"Competing interests","group":{"name":"EthicsHeading","label":"Ethics"}},{"value":"This study was conducted in compliance with 45 CFR \u00a746, which exempts research utilizing publicly available or de-identified data from institutional review board (IRB) oversight and participant informed consent requirements. Consequently, participant informed consent was not obtained.","order":2,"name":"Ethics","label":"Informed consent","group":{"name":"EthicsHeading","label":"Ethics"}}]}}