{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T19:21:42Z","timestamp":1790536902515,"version":"4.1.0"},"reference-count":59,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,11,30]],"date-time":"2023-11-30T00:00:00Z","timestamp":1701302400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"APR&amp;D multith\u00e9matique 2020","award":["CNRST-UM6P"],"award-info":[{"award-number":["CNRST-UM6P"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Avian influenza viruses pose significant threats to both the poultry industry and public health worldwide. Among them, the H9N2 subtype has gained substantial attention due to its high prevalence, especially in Asia, the Middle East, and Africa; its ability to reassort with other influenza viruses; and its potential to infect humans. This study presents a comprehensive phylogenetic and molecular analysis of H9N2 avian influenza viruses circulating in Morocco from 2021 to 2023. Through an active epidemiological survey, a total of 1140 samples (trachea and lungs) and oropharyngeal swabs pooled into 283 pools, collected from 205 farms located in 7 regions of Morocco known for having a high density of poultry farms, were analyzed. Various poultry farms were investigated (159 broiler farms, 24 layer farms, 10 breeder farms, and 12 turkey breeder farms). A total of 21 AI H9N2 strains were isolated, and in order to understand the molecular evolution of the H9N2 avian influenza virus, their genetic sequences were determined using the Sanger sequencing technique. Phylogenetic analysis was performed using a dataset comprising global H9N2 sequences to determine the genetic relatedness and evolutionary dynamics of the Moroccan strains. The results revealed the continued circulation and diversification of H9N2 avian influenza viruses in Morocco during the study period. Real-time RT-PCR showed a positivity rate of 35.6% (73\/205), with cycle threshold values ranging from 19.2 to 34.9. The phylogenetic analysis indicated that all Moroccan strains belonged to a G1-like lineage and regrouped into two distinct clusters. Our newly detected isolates aggregated distinctly from the genotypes previously isolated in Morocco, North and West Africa, and the Middle East. This indicats the potential of virus evolution resulting from both national circulation and cross-border transmission. A high genetic diversity at both nucleotide and amino-acid levels was observed among all the strains isolated in this study, as compared to H9N2 strains isolated in Morocco since 2016, which suggests the co-circulation of genetically diverse H9N2 variants. Newly discovered mutations were detected in hemagglutinin positions 226, 227, and 193 (H3 numbering), which highlights the genetic evolution of the H9N2 AIVs. These findings contribute to our understanding of the evolution and epidemiology of H9N2 in the region and provide valuable insights for the development of effective prevention and control strategies against this emerging avian influenza subtype.<\/jats:p>","DOI":"10.3390\/v15122355","type":"journal-article","created":{"date-parts":[[2023,11,30]],"date-time":"2023-11-30T09:37:54Z","timestamp":1701337074000},"page":"2355","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Low Pathogenic Avian Influenza H9N2 Viruses in Morocco: Antigenic and Molecular Evolution from 2021 to 2023"],"prefix":"10.3390","volume":"15","author":[{"given":"Oumayma","family":"Arbani","sequence":"first","affiliation":[{"name":"Department of Veterinary Pathology and Public Health, Institut Agronomique et V\u00e9t\u00e9rinaire Hassan II, Rabat 10000, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9632-5499","authenticated-orcid":false,"given":"Mariette F.","family":"Ducatez","sequence":"additional","affiliation":[{"name":"Laboratoire Interactions H\u00f4tes-Agents Pathog\u00e8nes (IHAP), Toulouse University, INRAE, ENVT, 31300 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Salma","family":"Mahmoudi","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology and Molecular Biology, Department of Biology, Faculty of Sciences, Mohamed V University in Rabat, 4 Avenue Ibn Battouta, Rabat 10106, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fai\u00e7al","family":"Salamat","sequence":"additional","affiliation":[{"name":"Department of Veterinary Pathology and Public Health, Institut Agronomique et V\u00e9t\u00e9rinaire Hassan II, Rabat 10000, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8033-2117","authenticated-orcid":false,"given":"Slimane","family":"Khayi","sequence":"additional","affiliation":[{"name":"Biotechnology Research Unit, CRRA-Rabat, National Institute of Agricultural Research, Rabat 10101, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3090-2630","authenticated-orcid":false,"given":"Mohamed","family":"Mouahid","sequence":"additional","affiliation":[{"name":"Mouahid Veterinary Clinic, Temara 12000, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5069-3947","authenticated-orcid":false,"given":"Karim M.","family":"Selim","sequence":"additional","affiliation":[{"name":"Reference Laboratory for Veterinary Quality Control on Poultry Production, Agriculture Research Center, Animal Health Research Institute, Giza 12618, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Faouzi","family":"Kichou","sequence":"additional","affiliation":[{"name":"Department of Veterinary Pathology and Public Health, Institut Agronomique et V\u00e9t\u00e9rinaire Hassan II, Rabat 10000, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ikram","family":"Ouchhour","sequence":"additional","affiliation":[{"name":"Department of Veterinary Pathology and Public Health, Institut Agronomique et V\u00e9t\u00e9rinaire Hassan II, Rabat 10000, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed","family":"El Houadfi","sequence":"additional","affiliation":[{"name":"Department of Veterinary Pathology and Public Health, Institut Agronomique et V\u00e9t\u00e9rinaire Hassan II, Rabat 10000, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1803-3746","authenticated-orcid":false,"given":"Siham","family":"Fellahi","sequence":"additional","affiliation":[{"name":"Department of Veterinary Pathology and Public Health, Institut Agronomique et V\u00e9t\u00e9rinaire Hassan II, Rabat 10000, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"916","DOI":"10.1016\/S0140-6736(99)03311-5","article-title":"Human Infection with Influenza H9N2","volume":"354","author":"Peiris","year":"1999","journal-title":"Lancet"},{"key":"ref_2","first-page":"10","article-title":"Genetic Determinants of Receptor-Binding Preference and Zoonotic Potential of H9N2 Avian Influenza Viruses","volume":"95","author":"Peacock","year":"2020","journal-title":"J. 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