中国人兽共患病学报2025，Vol.41Issue(12)：1248-1254,7.DOI:10.3969/j.issn.1002-2694.2025.00.184
2021-2024年长沙市活禽市场环境中H5N6亚型禽流感病毒基因特征和遗传进化分析
Genetic characteristics and genetic evolution analysis of H5N6 subtype avian influenza virus in live poultry market environments in Changsha City from 2021 to 2024
摘要
Abstract
The H5N6 subtype of avian influenza virus(AIV)poses a persistent threat to public health,because of its high patho-genicity and cross-species transmission potential.This study analyzed the epidemiological characteristics,genetic evolution,and mo-lecular variations of H5N6 viruses in live poultry markets in Changsha,Hunan Province,from 2021 to 2024,to assess their transmis-sion risks and provide a scientific basis for prevention and control strategies.In this study,environmental specimens from live poultry markets in nine districts and counties of Changsha were monitored,and influenza A virus and its subtypes were detected with real-time fluorescence RT-PCR.H5 avian influenza virus antibodies in poultry workers' sera were detected with horse blood cell hemagglu-tination inhibition tests.H5N6 nucleic acid positive samples were screened through second-generation sequencing,and sequences with high consistency with the nucleic acid sequence of the strain in this study were downloaded from the NCBI and GISAID databases.The sequences were spliced in CLC Genomics Workbench software,and the phylogenetic trees of the HA and NA genes were con-structed in MEGA7 software.Key amino acid sites and HA glycosylation sites were analyzed.A total of 441 specimens were tested from 2021 to 2024,and the positivity rate of influenza A virus was 84.58％(373/441).The positivity rate of the H5 subtype was 14.29％(63/441),and the mixed positivity rate of H5+H9 was 13.38％(59/441).One case of H5 avian influenza virus antibody was detected in the sera from occupationally exposed people.Ten H5N6 nucleic acid-positive specimens were selected for sequencing,and six com-plete HA and NA sequences were obtained.Consistency analysis indicated that the six H5N6 viruses were highly homologous to human or avian isolates from Guangdong,Hunan,Henan,Guangxi,Qinghai,and other areas,with nucleotide consistency reaching 99.06％-99.86％.Genetic evolution results indicated that the HA gene belonged to the clade 2.3.4.4b branch.The NA gene for the five strains(2021-2023)and the H5N6 type stem-deficient strains clustered into an independent evolutionary branch,and one strain(2024)was located in another evolutionary branch with the H5N6 and H6N6 type stem-complete strains.Molecular feature analysis demon-strated that the HA protein cleavage sites of all strains contained polybasic amino acids(RERRRKR ↓ GLF/REKRRKR ↓ GLF),in agreement with the characteristics of highly pathogenic avian influenza.The HA protein had S127P,S137A,and T160A mutations,and a glycosylation site loss at position 158,which enhances the virus's ability to bind the human SAα-2,6-Gal receptor.The live poultry markets in Changsha showed severe contamination with H5N6 virus.Sequencing results indicated that the strain in this study belonged to the highly pathogenic H5N6 avian influenza strain of the clade 2.3.4.4b branch and has potential for cross-species trans-mission.Strengthening market environment monitoring,improving protective measures for employees,and strengthening biosafety management are recommended to effectively block the spread of the virus.关键词
H5N6禽流感病毒/活禽市场/遗传进化/分子特征/跨物种传播Key words
H5N6 avian influenza virus/live poultry markets/genetic evolution/molecular characteristics/cross-species trans-mission分类
医药卫生引用本文复制引用
李灵之,欧新华,张如胜,姚栋,黄政,裴瑞青,肖姗..2021-2024年长沙市活禽市场环境中H5N6亚型禽流感病毒基因特征和遗传进化分析[J].中国人兽共患病学报,2025,41(12):1248-1254,7.基金项目
湖南省卫生健康高层次人才重大科研专项(No.R2023169) （No.R2023169）
湖南省自然科学基金(No.2023JJ60070) （No.2023JJ60070）
长沙市卫健委科研立项(No.KJ-B2023099) （No.KJ-B2023099）
长沙市自然科学基金(No.kq2403183) Hunan Province's Major Scientific Research Project for High-level Health Talents(No.R2023169) （No.kq2403183）
Hunan Natural Science Foundation(No.2023JJ60070) （No.2023JJ60070）
Changsha Municipal Health Commission Scientific Research Project(No.KJ-B2023099) （No.KJ-B2023099）
Changsha Natural Science Foundation(No.kq2403183) （No.kq2403183）
