Genome sequences of H7N9 avian influenza virus in poultry-related environment in Henan Province in 2023
10.3760/cma.j.cn112309-20230912-00074
- VernacularTitle:2023年河南省外环境H7N9禽流感病毒的基因组序列分析
- Author:
Bicong WU
1
;
Xue LUO
;
Shidong LU
;
Yun SONG
;
Baifan ZHANG
;
Haiyan WEI
;
Yifei NIE
;
Hui XIA
;
Sijia WAN
;
Ying YE
;
Xueyong HUANG
;
Wanshen GUO
;
Hongxia MA
Author Information
1. 河南省疾病预防控制中心传染病预防控制所，河南省传染病病原生物重点实验室，郑州 450016
- Keywords:
Avian influenza virus;
H7N9;
Live poultry market;
Genetic evolution;
Mutation
- From:
Chinese Journal of Microbiology and Immunology
2024;44(5):377-381
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the genetic evolution and molecular characteristics of H7N9 avian influenza virus (AIV) isolated in a live poultry market.Methods:Samples such as poultry feces, sewage, and hair removal machine and chopping board swabs were collected. Real-time fluorescent quantitative PCR was used to detect influenza A virus and H7N9 AIV in the samples. The whole genome of H7N9 AIV was amplified with influenza A virus universal primers and sequenced. BLAST and MEGA X were used for sequence alignment, phylogenetic analysis and molecular characterization.Results:Seven poultry-related environment samples were collected in the live poultry market in Xuchang city in February 2023, and four were positive for H7N9 AIV. The whole genome sequences of three H7N9 AIV isolates were successfully obtained, and the isolates shared high nucleotide identity in different genes (98.37%-100.00%). BLAST analysis showed they were highly identical to H7N9 strains isolated from domestic poultry in China from 2020 to 2021. Genetic evolution analysis showed that the three isolates clustered in the same branch and were closer to the recent environmental isolates than to the recent strains isolated from human or avian. Through comparison with the sequences of the representative strains in different periods, it was found that the isolated strains in this study showed high avian pathogenicity with four amino acids KRAA inserted at the cleavage site; the hemagglutinin receptor-binding site was QSG, which was an avian binding receptor; there was a G186I mutation in hemagglutinin. Mammalian-adaptive mutation E627K was not detected in polymerase basic protein 2. Mutations (R292K and I38T) associated with drug resistance to neuraminidase inhibitor (oseltamivir) and polymerase acidic protein inhibitor (baloshavir) were not detected, suggesting that these isolates remained susceptible to these drugs. A S31N mutation was found in M2 protein, indicating they were resistant to alkamines.Conclusions:The three H7N9 AIV strains isolated in the live poultry market have high avian pathogenicity, but there are no significant increase in mutations related to the binding ability to human receptors, mammalian pathogenicity, viral transmissibility, or drug resistance as compared with previous representative strains causing human or avian infection.
