#Genetic characterization of highly pathogenic avian #influenza #H5N8 virus isolated from commercial #poultry #farms in #Egypt reveals zoonotic potential
Abstract Highly pathogenic avian influenza (HPAI) H5N8 virus, first identified in late 2016 in Egypt, continues to circulate and has replaced the previously dominant HPAI H5N1 virus of clade 2.2.1. In this study, HPAI H5N8 was detected on 23 commercial poultry farms in Egypt . Complete genome sequences of three isolates collected in 2021 were obtained using next-generation sequencing (NGS) and subjected to genetic characterization. Phylogenetic analysis showed these isolates to belong to clade 2.3.4.4b, comprising two genotypes: EA-2021-Q and EA-2020-A . Molecular analysis of the haemagglutinin (HA) protein revealed the presence of T156A and V538A substitutions in the duck isolate and an N183S substitution in the chicken isolate . Several additional nonsynonymous mutations were identified, including 147I and 504V in the PB2 protein , 127V, 672L, and 550L in the PA protein , 64F and 69P in the M2 protein , and 42S in the NS1 protein . Comparative analysis of HA antigenic sites bet...