{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T06:05:24Z","timestamp":1792217124816,"version":"4.4.0"},"reference-count":33,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T00:00:00Z","timestamp":1767571200000},"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:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Post-COVID-19 respiratory infection dynamics require updated epidemiological characterization to inform clinical surveillance and public health strategy.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We analyzed 2484 patients with respiratory tract infections (September 2023\u2013February 2024) using comprehensive pathogen screening (29 viral, bacterial, and atypical targets) and cytokine quantification (12 cytokines).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Overall pathogen detection was 70.73%, with viral and bacterial identification in 40.42%(1004\/2484), 51.45%(1278\/2484) of cases respectively, and co-infections in 31.88% (predominantly\n                      <jats:italic>Haemophilus influenzae<\/jats:italic>\n                      -virus). Pediatric patients (&amp;lt;18 years) showed significantly higher positivity (74.1% vs. 63.2%,\n                      <jats:italic>P<\/jats:italic>\n                      &amp;lt; 0.05) with viral predominance (41.57% vs. 37.84%), while adults showed bacterial predominance (57.38% vs. 38.23%). Pneumonia risk exhibited age-pathogen specificity:\n                      <jats:italic>Mycoplasma pneumoniae<\/jats:italic>\n                      posed the highest risk in children (41.1% pneumonia rate) versus\n                      <jats:italic>influenza B<\/jats:italic>\n                      in adults (10.2% detection rate). Retrospective cytokine analysis (pre-pandemic 2018\u20132019 vs. post-pandemic 2023\u20132024) revealed post-pandemic suppression of IL-6 (6.12 vs.3.82 pg\/mL) and IL-8 (37.98 vs. 18.35 pg\/mL), with resurgence in 2024, particularly in pediatric and pneumonia cases (P&amp;lt;0.05).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>Post-pandemic respiratory pathogen epidemiology is characterized by heightened pediatric susceptibility to viral co-infections, bacterial pathogen persistence despite control measures, and dysregulated inflammatory responses. These findings warrant age-stratified diagnostic and surveillance approaches with adaptive public health strategies to reduce respiratory infection morbidity.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fcimb.2025.1634415","type":"journal-article","created":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T06:49:44Z","timestamp":1767595784000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":4,"title":["Epidemiological and immunological insights into respiratory infections in post-COVID-19"],"prefix":"10.3389","volume":"15","author":[{"given":"Ziyi","family":"Wang","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianpiao","family":"Cai","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yujie","family":"Sun","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mulatijiang","family":"Maimaiti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yiwei","family":"Liu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chenglin","family":"Yang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenjing","family":"Liu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabrina","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi","family":"Ren","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Chen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiwen","family":"Yang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yingchun","family":"Xu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Yi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,5]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1314","DOI":"10.1016\/S0140-6736(20)32117-6","article-title":"Living with the COVID-19 pandemic: act now with the tools we have","volume":"396","author":"Bedford","year":"2020","journal-title":"Lancet"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.2807\/1560-7917.ES.2020.25.2.1900112","article-title":"Mycoplasma pneumoniae infections, 11 countries in Europe and Israel 2011 to 2016","volume":"25","author":"Beeton","year":"2020","journal-title":"Euro surveillance: Bull. 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