{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T18:42:44Z","timestamp":1785436964700,"version":"3.56.0"},"reference-count":26,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,5,8]],"date-time":"2026-05-08T00:00:00Z","timestamp":1778198400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"WHO Eastern Mediterranean Regional Office"},{"id":[{"id":"https:\/\/ror.org\/01h4ywk72","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>Influenza sentinel surveillance in Libya was formally established in 2022 by the Libyan National Center for Disease Control (NCDC). Between 2022 and 2024, a total of 1864 nasopharyngeal specimens were collected from patients presenting with influenza-like illness and tested using the GeneXpert for influenza A virus, influenza B virus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and respiratory syncytial virus (RSV). Influenza A virus was detected in 21.1% (393\/1864) of samples and influenza B virus was detected in 5.4% of samples (100\/1864). SARS-CoV-2 and RSV were identified in 11.6% (216\/1864) and 4.1% (77\/1864) of specimens, respectively. A subset of 22 influenza A-positive samples was selected based on sample availability and sufficient remaining volume after the initial test for confirmatory testing and further molecular characterization. Real-time RT-PCR subtyping identified 11 A(H1N1)pdm09 and four A(H3N2) viruses. Whole-genome sequencing was successfully performed for 11 isolates, followed by phylogenetic analysis. Genetic characterization revealed that all A(H1N1)pdm09 viruses belonged to clade 6B.1A.5a.2a (5a.2a), while A(H3N2) viruses clustered within clade 3C.2a1b.2a.2a.3a.1 (2a.3a.1) were based on hemagglutinin gene mutations. No neuraminidase mutations associated with antiviral resistance were detected. This study represents the first molecular and phylogenetic characterization of circulating human influenza viruses in Libya, with sequence data submitted to the Global Initiative on Sharing All Influenza Data (GISAID) to establish baseline genetic data for influenza viruses in Libya.<\/jats:p>","DOI":"10.3390\/tropicalmed11050127","type":"journal-article","created":{"date-parts":[[2026,5,11]],"date-time":"2026-05-11T20:14:16Z","timestamp":1778530456000},"page":"127","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Sentinel Surveillance of Influenza A in Libya: Subtyping and Genomic Analysis During Recent Seasons (2022\u20132024)"],"prefix":"10.3390","volume":"11","author":[{"given":"Mahmud","family":"Azbida","sequence":"first","affiliation":[{"name":"Department of Medical Laboratories, Faculty of Medical Technology, University of Tripoli, Tripoli 13275, Libya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sana","family":"Ferjani","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Charles Nicolle Hospital, Tunis 1006, Tunisia"},{"name":"LR99ES09AMR Research Laboratory, Faculty of Medicine of Tunis, University of Tunis ElManar, Tunis 1007, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Omar","family":"Elahmer","sequence":"additional","affiliation":[{"name":"National Center for Disease Control, Tripoli 71171, Libya"},{"name":"Department of Dental Technology, Faculty of Medical Technology, University of Tripoli, Tripoli 13275, Libya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rmadhan","family":"Osman","sequence":"additional","affiliation":[{"name":"Department of Public Health, Faculty of Medical Technology, University of Tripoli, Tripoli 13275, Libya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-7362-5492","authenticated-orcid":false,"given":"Salem","family":"Shenaisheh","sequence":"additional","affiliation":[{"name":"National Center for Disease Control, Tripoli 71171, Libya"},{"name":"Community and Family Medicine Department, Faculty of Medicine, University of Misurata, Misurata 2478, Libya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amal","family":"Barakat","sequence":"additional","affiliation":[{"name":"Regional Office for the Eastern Mediterranean, World Health Organization, Cairo 7608, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salma","family":"Abid","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Charles Nicolle Hospital, Tunis 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adem","family":"Eljerbi","sequence":"additional","affiliation":[{"name":"National Center for Disease Control, Tripoli 71171, Libya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7529-7430","authenticated-orcid":false,"given":"Abdulwahab","family":"Kammon","sequence":"additional","affiliation":[{"name":"National Research Centre for Tropical and Transboundary Diseases, Alzintan 61053, Libya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ameni","family":"Sallemi","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Pharmacology, National Center Chalbibelkahia of Pharmacovigilance of Tunis, 9 Avenue Dr. Zouhaier Essafi 1006 Bab Souika, Tunis 1007, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haider","family":"El-Saeh","sequence":"additional","affiliation":[{"name":"National Center for Disease Control, Tripoli 71171, Libya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6590-2406","authenticated-orcid":false,"given":"Ilhem","family":"Boutiba-Ben Boubaker","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Charles Nicolle Hospital, Tunis 1006, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1750-1448","authenticated-orcid":false,"given":"Ibrahim","family":"Eldaghayes","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Tripoli, Tripoli 13662, Libya"},{"name":"Influenza Focal Point, National Center for Disease Control, Tripoli 71171, Libya"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,8]]},"reference":[{"key":"ref_1","unstructured":"World Health Organization (2025, December 15). 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