{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T08:46:08Z","timestamp":1771922768284,"version":"3.50.1"},"reference-count":58,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T00:00:00Z","timestamp":1768953600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:p>Influenza is an acute respiratory infectious disease caused by the influenza virus, which has been circulating in humans for over a century. In contrast, COVID-19, caused by the novel SARS-CoV-2, emerged recently in December 2019. Following nearly four years of pandemic, the acute phase of SARS-CoV-2 has transitioned towards an endemic state, suggesting a trend of long-term coexistence with humans. Concurrent or sequential coinfection with influenza and SARS-CoV-2 has been clinically observed to exacerbate pulmonary pathology and systemic inflammation in affected individuals. This review discusses the impact and elucidates the potential underlying mechanisms by which influenza and SARS-CoV-2 coinfection aggravates local lung injury and systemic host responses, aiming to inform improved prevention and clinical management strategies.<\/jats:p>","DOI":"10.3389\/fcimb.2026.1725731","type":"journal-article","created":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T06:44:57Z","timestamp":1768977897000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Local and systemic host responses to influenza and concurrent or sequential SARS-CoV-2 infection"],"prefix":"10.3389","volume":"16","author":[{"given":"Tong","family":"Zhu","sequence":"first","affiliation":[{"name":"Department of Neonatology and Institute of Pediatrics, Children\u2019s Medical Center, First Hospital of Jilin University, Jilin University","place":["Changchun, Jilin, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Liying","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Molecular Biology, College of Basic Medical Sciences, Jilin University","place":["Changchun, Jilin, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chaoying","family":"Yan","sequence":"additional","affiliation":[{"name":"Department of Neonatology and Institute of Pediatrics, Children\u2019s Medical Center, First Hospital of Jilin University, Jilin University","place":["Changchun, Jilin, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,21]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2020.552909","article-title":"Comparative review of SARS-CoV-2, SARS-CoV, MERS-CoV, and influenza a respiratory viruses","volume":"11","author":"Abdelrahman","year":"2020","journal-title":"Front. 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