{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T01:46:15Z","timestamp":1790646375289,"version":"4.1.0"},"reference-count":46,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,3,4]],"date-time":"2022-03-04T00:00:00Z","timestamp":1646352000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"PHC Toubkal 19\/76","award":["41439WM"],"award-info":[{"award-number":["41439WM"]}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["CEIRS HHSN272201400006C"],"award-info":[{"award-number":["CEIRS HHSN272201400006C"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Low pathogenic H9N2 avian influenza (LPAI H9N2) is considered one of the most important diseases found in poultry (broiler, laying hens, breeding chickens, and turkeys). This infection causes considerable economic losses. The objective of this work was to monitor and assess the presence of avian influenza virus (AIV) H9N2 in eight different regions of Morocco using real-time RT-PCR, and to assess the phylogenetic and molecular evolution of the H9N2 viruses between 2016 and 2019. Field samples were collected from 108 farms suspected of being infected with LPAI H9N2 virus. Samples were analyzed using H9N2-specific real-time RT-PCR. Highly positive samples were subjected to virus isolation and seven isolates were fully sequenced. Low pathogenic H9N2 avian influenza virus was introduced in Morocco in 2016. We show that in 2018\u20132019, the virus was still present irrespective of vaccination status. Phylogenetic and molecular analyses showed mutations related to virulence, although our viruses were related to 2016 Moroccan viruses and grouped in the G1 lineage. Specific amino acid substitutions were identified in Moroccan H9N2 viruses that are believed to lead to increased resistance to antiviral drugs.<\/jats:p>","DOI":"10.3390\/v14030529","type":"journal-article","created":{"date-parts":[[2022,3,6]],"date-time":"2022-03-06T20:40:38Z","timestamp":1646599238000},"page":"529","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Avian Influenza a H9N2 Viruses in Morocco, 2018\u20132019"],"prefix":"10.3390","volume":"14","author":[{"given":"Fatima-Zohra","family":"Sikht","sequence":"first","affiliation":[{"name":"Avian Pathology Unit, Department of Veterinary Pathology and Public Health, Agronomy and Veterinary Institute Hassan II, Rabat B.P. 6202, Morocco"},{"name":"IHAP, Toulouse University, INRAE, ENVT, 31300 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mariette","family":"Ducatez","sequence":"additional","affiliation":[{"name":"IHAP, Toulouse University, INRAE, ENVT, 31300 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charifa Drissi","family":"Touzani","sequence":"additional","affiliation":[{"name":"Avian Pathology Unit, Department of Veterinary Pathology and Public Health, Agronomy and Veterinary Institute Hassan II, Rabat B.P. 6202, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adam","family":"Rubrum","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, St. Jude Children\u2019s Research Hospital, Memphis, TN 38105, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4397-7132","authenticated-orcid":false,"given":"Richard","family":"Webby","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, St. Jude Children\u2019s Research Hospital, Memphis, TN 38105, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed","family":"El Houadfi","sequence":"additional","affiliation":[{"name":"Avian Pathology Unit, Department of Veterinary Pathology and Public Health, Agronomy and Veterinary Institute Hassan II, Rabat B.P. 6202, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nour-Said","family":"Tligui","sequence":"additional","affiliation":[{"name":"Anatomo-Pathology Unit, Department of Veterinary Pathology and Public Health, Agronomy and Veterinary Institute Hassan II, Rabat B.P. 6202, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6590-1713","authenticated-orcid":false,"given":"Christelle","family":"Camus","sequence":"additional","affiliation":[{"name":"IHAP, Toulouse University, INRAE, ENVT, 31300 Toulouse, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siham","family":"Fellahi","sequence":"additional","affiliation":[{"name":"Avian Pathology Unit, Department of Veterinary Pathology and Public Health, Agronomy and Veterinary Institute Hassan II, Rabat B.P. 6202, Morocco"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,4]]},"reference":[{"key":"ref_1","unstructured":"(2021, August 03). 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