Molecular evolution of the hemagglutinin gene and epidemiological insight into low-pathogenic avian influenza H9N2 viruses in Egypt. (May 2021)

• Record Type: Journal Article
• Authors: Adel, Amany; Mosaad, Zienab; Shalaby, Azhar G.; Selim, Karim; Samy, Mohamed; Abdelmagid, Marwa A.; Hagag, Naglaa M.; Arafa, Abdel Satar; Hassan, Wafaa M.; Shahien, Momtaz A.
• Is Part Of: Research in veterinary science. Volume 136(2021)
• Page Start: 540
• Page End: 549
• Publication Date: 2021-05
• Subjects: LPAI H9N2 -- Hemagglutinin -- Antigenic sites -- Receptor binding sites -- Egypt; RBS Receptor binding sites -- LPAI Low pathogenic avian influenza -- AIV Avian Influenza Virus -- HA Hemagglutinin -- NA Neuraminidase -- NCBI National Center for Biotechnology Information -- SLAC Single-Likelihood Ancestor Counting -- FUBAR Fast, Unconstrained Bayesian Approximation -- FEL Fixed Effects Likelihood -- ML maximum-likelihood; Veterinary medicine -- Periodicals; Veterinary Medicine -- Periodicals; Médecine vétérinaire -- Périodiques; Médecine vétérinaire -- Recherche -- Périodiques; Diergeneeskunde; 636.089
• DOI: 10.1016/j.rvsc.2021.04.006
• Languages: English
• ISSNs: 0034-5288

Abstract

Abstract: Despite the low pathogenicity of the H9N2 avian influenza viruses, they can induce severe economic losses in various poultry sectors in conjunction with other factors. In Egypt, low-pathogenic avian influenza (LPAI) H9N2 became endemic in 2011 and has undergone continuous genetic evolution since then. The regular monitoring of the evolution of the virus is necessary to control its spread. During 2017–2020, there were 44 positive samples isolated, and these viruses were genetically sequenced to determine the hemagglutinin (HA) gene circulating in Egypt. The molecular analysis revealed at least nine changes in amino acid residues in comparison with the reference Egyptian strain from the original introduction in 2011 (A/qu/Egypt/113413v/2011), with a similarity of 95%–96%. Amino acid residues 180 and 216 are the most important residues in terms of positive selection pressure. Phylogenetically, the new Egyptian H9N2 viruses in 2017–2020 belonged to a new subcluster related to the strains that had been circulating since 2015. Comparative analysis of the HA gene of LPAI H9N2 viruses in Egypt from 2011 to 2020 supports a continuous evolution through the years with persistent markers. Highlights: Annual surveillance for is very important to follow up the evolution of LPAI H9N2. LPAI H9N2 shows continuous genetic evolution through the years. The phylogenetic analysis of HA reveals an evidence in bi-directional diffusion between Egypt and Israel. The spatial analysis supports the role of Lower Egypt regions in dissemination of the virus along Egypt.