{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T12:38:37Z","timestamp":1772195917501,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T00:00:00Z","timestamp":1772150400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"SK bioscience"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: Influenza remains a significant public health burden. Although vaccination is the most effective preventive strategy, evidence on influenza vaccine effectiveness (VE) in Korea remains fragmented. Methods: A systematic review and meta-analysis were conducted on real-world Korean influenza VE studies published from January 2016 to October 2025. Literature research was performed in PubMed, Embase, and Web of Science. Eligible studies evaluated influenza VE using real-world data sources. Pooled VE estimates were calculated using a random-effects model and stratified by age group and virus type. Results: A total of 2922 records were identified, of which nine studies met the inclusion criteria and eight were included in the meta-analysis. Eight of nine studies were conducted in hospital settings. Five studies targeted adults (including two focusing on those aged \u2265 65 years), and four targeted children. Six of the nine studies evaluated single influenza seasons, while the remaining three covered multiple seasons. Statistically significant VE was observed among adults (23.6%, 95% confidence interval [CI]: 13.8 to 32.2), children (25.2%, 95% CI: 8.2 to 39.0) and against influenza A in children (32.4%, 95% CI: 17.7 to 44.4). Conclusions: This study synthesized a decade of fragmented VE evidence in Korea. Findings suggest suboptimal effectiveness compared to global estimates, highlighting the need for further evaluation of alternative vaccine platforms, including cell-based vaccines, within Korea\u2019s national immunization strategy.<\/jats:p>","DOI":"10.3390\/vaccines14030217","type":"journal-article","created":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T11:22:57Z","timestamp":1772191377000},"page":"217","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Influenza Vaccine Effectiveness in Korea: A Systematic Review and Meta-Analysis of Real-World Evidence from the Past Decade"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8197-3212","authenticated-orcid":false,"given":"Hye Su","family":"Jeong","sequence":"first","affiliation":[{"name":"Medical Affairs, SK bioscience, 38, Yeongudanji-ro, Yeonsu-gu, Incheon 21984, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9939-3737","authenticated-orcid":false,"given":"Hye Young","family":"Kim","sequence":"additional","affiliation":[{"name":"Medical Affairs, SK bioscience, 38, Yeongudanji-ro, Yeonsu-gu, Incheon 21984, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3243","DOI":"10.1001\/archinte.160.21.3243","article-title":"Clinical signs and symptoms predicting influenza infection","volume":"160","author":"Monto","year":"2000","journal-title":"Arch. 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