Genotyping and reassortment analysis of highly pathogenic avian influenza viruses H5N8 and H5N2 from Egypt reveals successive annual replacement of genotypes.

Genotyping and reassortment analysis of highly pathogenic avian influenza viruses H5N8 and H5N2 from Egypt reveals successive annual replacement of genotypes. Infect Genet Evol. 2020 May 23;:104375 Authors: Hassan KE, Saad N, Abozeid HH, Shany S, El-Kady MF, Arafa A, El-Sawah AAA, Pfaff F, Hafez HM, Beer M, Harder T Abstract Highly pathogenic (HP) H5N1, clade 2.2.1, and low pathogenic avian influenza (LPAI) H9N2 viruses, G1-B lineage, are endemic in poultry in Egypt and have co-circulated for almost a decade. Surprisingly, no inter-subtypic reassortment events have been reported from the field during that time. After the introduction of HPAIV H5N8, clade 2.3.4.4b, in Egyptian poultry in 2016, suddenly HP H5N2 reassortants with H9N2 viruses emerged. The current analyses focussed on studying 32 duck flocks, 4 broiler chicken flocks, and 1 turkey flock, suffering from respiratory manifestations with moderate to high mortality reared in two Egyptian governorates during 2019. Real-time RT-PCR substantiated the presence of HP H5N8 in 21 of the 37 investigated flocks with mixed infection of H9N2 in two of them. HP H5N1 was not detected. Full hemagglutinin (HA) sequencing of 10 samples with full-genome sequencing of three of them revealed presence of a single genotype. Very few substituting mutations in the HA protein were detected versus previous Egyptian HA sequences of that clade. Interestingly, amino acid substitutions in the Matrix (M2)...
Source: Infection, Genetics and Evolution - Category: Genetics & Stem Cells Authors: Tags: Infect Genet Evol Source Type: research