我国2021-2023年鸡传染性支气管炎病毒流行趋势研究  

Epidemic Trend of the Infectious Bronchitis Virus in Chickens in China from 2021 to 2023

作　　者：张明伟 赵君 孙璐 黄英 张国中[1] 赵烨[1] ZHANG Mingwei;ZHAO Jun;SUN Lu;HUANG Ying;ZHANG Guozhong;ZHAO Ye(College of Veterinary Medicine,China Agricultural University,Beijing 100193,China;Animal Husbandry and Veterinary Station,Baofan,Pengxi 629100,China)

机构地区：[1]中国农业大学动物医学院,北京100193 [2]四川省蓬溪县宝梵镇畜牧兽医站,蓬溪629100

出　　处：《病毒学报》2024年第5期1099-1104,共6页Chinese Journal of Virology

基　　金：国家重点研发计划(项目号:2022YFD1801004-3),题目:禽病毒性疫病新型疫苗创制。

摘　　要：传染性支气管炎病毒(Infectious bronchitis virus,IBV)是造成临床鸡群出现呼吸系统和泌尿生殖系统疾病的重要病原,病毒本身易发生突变和重组,造成新型变异毒株的不断出现,且与常规疫苗毒株之间的抗原性存在很大差异,给临床免疫防控造成了巨大困难。因此对当前我国流行的IBV毒株进行持续性的分子流行病学监测,对于有针对性的研发新型IBV疫苗具有重要的指导意义和参考价值。本研究对2021-2023年我国临床分离到的32株IBV毒株进行了S1蛋白编码基因的序列测定和分析,并对其共同变异位点进行了蛋白功能性预测。研究结果发现,在32株IBV毒株中有22株位于GI-19分支,且进一步独立形成两个小的分支,分支内毒株的同源性均大于98.08%,分支之间的同源性在96.35%~98.02%,而与本实验室分离到的早期经典GI-19分支毒株-强毒株SD同源性低于95.33%,与自然致弱疫苗株SZ之间的同源性在95.99%~98.04%。2株毒株位于GI-22分支,与LDT3毒株的遗传距离较近。另外有3株分离株为GI-1和GI-13类疫苗毒株。需要注意的是,GVI-1基因型分离株逐渐增多(4/32),与常规疫苗株同源性约为68%;另有1株分离株与其余基因型毒株同源性均<78%,需要对其致病性和免疫原性进一步分析。综上所述,我国当前IBV流行毒株仍然以GI-19分支为主,但与此同时新分离株与经典毒株之间出现了较大变化,呈现出独立小分支的演变趋势,需要引起关注和重视。The infectious bronchitis virus(IBV)is an important pathogen causing respiratory and genitourinary diseases in chickens.The virus is prone to mutation and recombination,which results in the continuous emergence of new mutants.These strains show significant antigenic differences from conventional vaccine strains,thereby posing substantial challenges to prevention and control.Therefore,continuous molecular epidemiological surveillance of IBV strains prevalent in China has important guidance and reference values for the targeted development of new IBV vaccines.The S1 protein-coding genes of 32 IBV strains isolated in China from 2021 to 2023 were sequenced and analyzed.Their common variation sites were predicted for protein function.Twenty-two of the 32 IBV strains were located in the GI–19 cluster and were divided into two small subclusters independently.The homology of the strains within the subcluster was>98.08%.The homology between subclusters was between 96.35%and 98.02%.However,the homology with the early classical GI–19 virulent strain isolated by our research team(SD strain)was<95.33%.The homology with the naturally attenuated vaccine strain SZ was between 95.99%and 98.04%.Two strains were clustered with the GI-22genotype strain LDT3.The other three isolates were GI-1 and GI-13 vaccine-like strains.The isolation rate of the GVI-1 genotype increased(4/32),of which the homology with conventional vaccine strains was about 68%.Another isolated strain shared<78%homology with other genotype strains,and further analysis of their pathogenicity and immunogenicity was needed.In summary,the epidemic strains of IBV in China are dominated by GI-19 genotype strains but.simultaneously,great changes have taken place between new isolates and classical strains,showing an evolution trend of independent small branches,which merits attention.

关 键 词：传染性支气管炎病毒 分离株 流行趋势 

分 类 号：S855.3[农业科学—临床兽医学]