Genetic features of avian influenza (A/H5N8) clade 2.3.4.4b isolated from quail in Egypt

• Published in: Virus research Vol. 350; p. 199482
• Main Authors: Elhusseiny, Mohamed H., Elsayed, Moataz M., Mady, Wesam H., Mahana, Osama, Bakry, Neveen R., Abdelaziz, Ola, Arafa, Abdel-Sattar, Shahein, Momtaz A., Eid, Samah, Naguib, Mahmoud M.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-12-2024; Elsevier
• Subjects: Avian influenza virus; Egypt; H5N8; Quail; Short Communication; Virus evolution; Avian influenza virus; Virus evolution; Quail; H5N8; Egypt; virus evolution; quail
• ISSN: 0168-1702; 1872-7492; 1872-7492
• DOI: 10.1016/j.virusres.2024.199482

•This study reports genetic analyses of the H5N8 virus in quail in Egypt.•The virus is phylogenetically related to other H5N8 viruses within clade 2.3.4.4b.•These findings support the spread of the H5N8 virus to other bird species in Egypt.•Recording mutations indicate their affinity for human-like receptors and increased virulence in mammals.•This calls for continuous surveillance and genetic monitoring of the influenza virus.
Several genotypes of the highly pathogenic avian influenza (HPAI) virus H5N8 subtype within clade 2.3.4.4b continue to circulate in different species of domestic birds across Egypt. It is believed that quail contribute to virus replication and adaptation to other gallinaceous poultry species and humans. This study provides genetic characterization of the full genome of HPAI H5N8 isolated from quail in Egypt. The virus was isolated from a commercial quail farm associated with respiratory signs. To characterize the genetic features of the detected virus, gene sequencing via Sanger technology and phylogenetic analysis were performed. The results revealed high nucleotide identity with the HPAI H5N8 virus from Egypt, which has multiple basic amino acid motifs PLREKRRKR/GLF at the hemagglutinin (HA) cleavage site. Phylogenetic analysis of the eight gene segments revealed that the quail isolate is grouped with HPAI H5N8 viruses of clade 2.3.4.4b and closely related to the most recent circulating H5N8 viruses in Egypt. Whole-genome characterization revealed amino acid preferences for avian receptors with few mutations, indicating their affinity for human-like receptors and increased virulence in mammals, such as S123P, S133A, T156A and A263T in the HA gene. In addition, the sequencing results revealed a lack of markers associated with influenza antiviral resistance in the neuraminidase and matrix-2 coding proteins. The results of the present study support the spread of HPAIV H5N8 to species other than chickens in Egypt. Therefore, continuous surveillance of AIV in different bird species in Egypt followed by full genomic characterization is needed for better virus control and prevention.