{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T19:32:18Z","timestamp":1791401538166,"version":"4.3.3"},"reference-count":32,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,3]],"date-time":"2025-10-03T00:00:00Z","timestamp":1759449600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>We investigated respiratory virus epidemiology in older adults across pre-pandemic (2007\u20132019), pandemic (2020\u20132022), and post-pandemic (2023\u20132024) periods, focusing on how public health interventions shaped surveillance, prevalence, and sex-specific trends. We conducted a retrospective cross-sectional study at a 1000-bed tertiary hospital in the Republic of Korea during 2007\u20132024, analyzing 4692 nasopharyngeal swab specimens collected from adults aged \u2265 65 years with suspected respiratory infections during 2007\u20132024. The specimens were tested for 15 respiratory viruses using multiplex real-time polymerase chain reaction. The outcomes included virus-specific detection rates and seasonal, sex-based and temporal trends before and after the COVID-19 pandemic. During the pre-pandemic period, older adults accounted for 13.2% of the tested individuals, which significantly increased to 52.0% in the later periods. Influenza A was the most frequently detected virus, followed by rhinovirus and human metapneumovirus. Influenza, RSV A\/B, and coronaviruses 229E and OC43 showed peak positivity in winter, parainfluenza virus type 3 peaked in summer, and rhinovirus circulated year-round. Virus circulation was markedly suppressed during 2020\u20132022 and partially rebounded during 2023\u20132024. This study highlights the shift in diagnostic access and epidemiologic patterns of respiratory virus infections in older adults following the COVID-19 pandemic.<\/jats:p>","DOI":"10.3390\/microorganisms13102301","type":"journal-article","created":{"date-parts":[[2025,10,3]],"date-time":"2025-10-03T15:26:54Z","timestamp":1759505214000},"page":"2301","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Epidemiological Shifts in Respiratory Virus Infections Among Older Adults (\u226565 Years) Before and After the COVID-19 Pandemic: An 18-Year Retrospective Study in the Republic of Korea"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-7003-8422","authenticated-orcid":false,"given":"Jeong Su","family":"Han","sequence":"first","affiliation":[{"name":"Department of Biomedical Laboratory Science, College of Health Sciences, Dankook University, Cheonan-si 31116, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-0934-8445","authenticated-orcid":false,"given":"Sung Hun","family":"Jang","sequence":"additional","affiliation":[{"name":"Department of Medical Laser, Graduate School of Medicine, Dankook University, Cheonan-si 31116, Republic of Korea"},{"name":"Research Center for Bio-Functional and Biocompatible Materials, Dankook University, Cheonan-si 31116, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8981-5705","authenticated-orcid":false,"given":"Jae-Sik","family":"Jeon","sequence":"additional","affiliation":[{"name":"Department of Biomedical Laboratory Science, College of Health Sciences, Dankook University, Cheonan-si 31116, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyung Bae","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Medical Laboratory Science, Seoyeong University, Paju-si 10843, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1534-563X","authenticated-orcid":false,"given":"Jae Kyung","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Laboratory Science, College of Health Sciences, Dankook University, Cheonan-si 31116, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,3]]},"reference":[{"key":"ref_1","first-page":"51","article-title":"Immunosenescence: Molecular mechanisms and diseases","volume":"8","author":"Liu","year":"2023","journal-title":"Signal Transduct. 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