The Evolution and Molecular Characteristics of Polymerase Complex of H9N2 Avian Influenza Viruses in Egypt

Abstract

H9N2 avian influenza virus is endemic in Egyptian domesticated birds since 2010.Dueto their mammalian-like traits, H9N2 have crossed the species barrier resulting in mildto moderate infections. Currently, the H9N2 virus's capacity to contribute their genes toother AIVs, creating high and low pathogenic IAVs that might cross species barriers andinfect people, is considered a global concern. It has been determined that the RNAdependent RNA polymerase of viruses (vRdRp) (polymerase complex) activitypossesses a crucial role in modulating AIVs host adaptability to mammals andcontrolling of the viral ability to cross species barrier. Our study is conducted to screenthe molecular progress of polymerase complex of H9N2 virus in Egypt, sequencing ofthe three genes of the polymerase complex and molecular characterization of theobtained sequences were achieved. Our findings showed the presence of some pointmutations in the three genes (PB2, PB1and PA) which had previously been linked toincreased viral replication, virulence, pathogenicity of avian influenza viruses inmammals.