Sequence characteristics and phylogenetic analysis of H9N2 subtype avian influenza A viruses detected from poultry and the environment in China, 2018

• DOI: 10.7717/peerj.12512
• Publication Date: 2021-12-20T10:25:36Z
• Authors: Xiaoyi Gao; Naidi Wang; Yuhong Chen; Xiaoxue Gu; Yuanhui Huang; Yang Liu; Fei Jiang; Jie Bai; Lu Qi; Shengpeng Xin; Yuxiang Shi; Chuanbin Wang; Yuliang Liu
• Keywords: Sequence (biology)

H9N2 subtype avian influenza A virus (AIV) is a causative agent that poses serious threats to both the poultry industry and global public health. In this study, we performed active surveillance identify AIVs from (chicken, duck, goose) environment of different regions in China, phylogenetically characterized sequences. AIV subtype-specific reverse transcription polymerase chain reaction (RT-PCR) showed 5.43% (83/1529) samples were positive, 87.02% (67/77) which AIVs. Phylogenetic analysis revealed all field viruses belonged Y280-like lineage, exhibiting 93.9–100% 94.6–100% homology hemagglutinin (HA) gene 94.4–100% 96.3–100% neuraminidase (NA) gene, at nucleotide (nt) amino acid (aa) levels, respectively. All shared relatively lower identities with vaccine strains, ranging 89.4% 97.7%. The aa sequence cleavage site (aa 333–340) HA isolated was PSRSSRG/L, characteristic low pathogenic (LPAIV). Notably, harbored eight glycosylation sites, whereas 218 NRT missing new 313 NCS inserted. had NGLMR as their receptor binding sites (RBS) position 224–229, showing high conservation many recently-isolated strains. isolates 226 Leucine (L), indicating ability bind sialic (SA) α, 2–6 mammals potential risk transmission humans. Our results suggest circulating populations have genetic variation infecting mammalian species are great significance when monitoring China.