{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T10:35:27Z","timestamp":1778322927482,"version":"3.51.4"},"reference-count":115,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2024,10,23]],"date-time":"2024-10-23T00:00:00Z","timestamp":1729641600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deanship of Graduate Studies and Scientific Research at Qassim University for financial support","award":["QU-APC-2024-9\/1"],"award-info":[{"award-number":["QU-APC-2024-9\/1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Avian influenza (AI) is an extremely contagious viral disease of domestic and wild birds that can spread rapidly among bird populations, inducing serious economic losses in the poultry industry. During the winter season 2021\u20132022, we isolated seventeen highly pathogenic avian influenza (HPAI) H5N8 viruses from outbreaks involving ducks in Egypt, occurring in both backyard and farm settings. The aim of this study was to pinpoint genetic key substitutions (KSs) that could heighten the risk of a human pandemic by influencing the virus\u2019s virulence, replication ability, host specificity, susceptibility to drugs, or transmissibility. To understand their evolution, origin, and potential risks for a human pandemic, whole-genome sequencing and phylogenetic analysis were conducted. Our analysis identified numerous distinctive mutations in the Egyptian H5N8 viruses, suggesting potential enhancements in virulence, resistance to antiviral drugs, and facilitation of transmission in mammals. In this study, at least five genotypes within one genome constellation of H5N8 viruses were identified, raising concerns about the potential emergence of novel viruses with altered characteristics through reassortment between different genotypes and distinct groups. These findings underscore the role of ducks in the virus\u2019s evolutionary process and emphasize the urgent need for enhanced biosecurity measures in domestic duck farms to mitigate pandemic risk.<\/jats:p>","DOI":"10.3390\/v16111655","type":"journal-article","created":{"date-parts":[[2024,10,23]],"date-time":"2024-10-23T09:07:04Z","timestamp":1729674424000},"page":"1655","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Phylogenetic Characterization of Novel Reassortant 2.3.4.4b H5N8 Highly Pathogenic Avian Influenza Viruses Isolated from Domestic Ducks in Egypt During the Winter Season 2021\u20132022"],"prefix":"10.3390","volume":"16","author":[{"given":"Noha","family":"Saad","sequence":"first","affiliation":[{"name":"Animal Health Research Institute, Agricultural Research Center, Giza 12618, Egypt"},{"name":"National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Ministry of Agriculture, Giza 12618, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mana","family":"Esaki","sequence":"additional","affiliation":[{"name":"Department of Pathogenetic and Preventive Veterinary Science, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"},{"name":"Joint Graduate School of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isshu","family":"Kojima","sequence":"additional","affiliation":[{"name":"Department of Pathogenetic and Preventive Veterinary Science, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"},{"name":"Joint Graduate School of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1358-6755","authenticated-orcid":false,"given":"Ahmed Magdy","family":"Khalil","sequence":"additional","affiliation":[{"name":"Department of Pathogenetic and Preventive Veterinary Science, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"},{"name":"Department of Zoonotic Diseases, Faculty of Veterinary Medicine, Zagazig University, Zagazig 44511, Egypt"},{"name":"United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi 753-8515, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shiori","family":"Osuga","sequence":"additional","affiliation":[{"name":"Department of Pathogenetic and Preventive Veterinary Science, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Momtaz A.","family":"Shahein","sequence":"additional","affiliation":[{"name":"Animal Health Research Institute, Agricultural Research Center, Giza 12618, Egypt"},{"name":"National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Ministry of Agriculture, Giza 12618, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7987-9884","authenticated-orcid":false,"given":"Kosuke","family":"Okuya","sequence":"additional","affiliation":[{"name":"Department of Pathogenetic and Preventive Veterinary Science, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"},{"name":"Joint Graduate School of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"},{"name":"Transboundary Animal Diseases Research Center, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7731-5321","authenticated-orcid":false,"given":"Makoto","family":"Ozawa","sequence":"additional","affiliation":[{"name":"Department of Pathogenetic and Preventive Veterinary Science, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"},{"name":"Transboundary Animal Diseases Research Center, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0871-6313","authenticated-orcid":false,"given":"Bader Y.","family":"Alhatlani","sequence":"additional","affiliation":[{"name":"Unit of Scientific Research, Applied College, Qassim University, Buraydah 52571, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"463","DOI":"10.20506\/rst.19.2.1230","article-title":"Highly pathogenic avian influenza","volume":"19","author":"Swayne","year":"2000","journal-title":"Rev. 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