【摘要】 鸡传染性支气管炎（Avian infectious bronchitis,IB）是由鸡传染性支气管炎病毒（Avian infectious bronchitis virus,IBV）引起的一种分布范围广泛、传染性较强，能对家禽养殖业造成重大经济损害的二类动物疫病。同其他RNA病毒一样，遗传变异方面为独特的套式转录方式，在复制过程中病毒基因组的不连续性和RNA聚合酶校对不完全性，致使碱基在复制过程中易发生替换、缺失和插入，进一步造成了该病毒高突变性的特征。近年来多个研究表明，IBV产生变异株的主要原因并不是点突变，而是滥用疫苗、盲目免疫所造成的基因重组，在自然选择以及外部高强度免疫压力的双重影响下，促使IBV不断演化变异产生新的强毒株。着重论述了近年来IBV在全球各地的流行状况，深入分析了IBV遗传演化发生原因，为该病的疫苗防控提供可靠的数据支撑。更多还原

【Abstract】 Avian infectious bronchitis(IB) is a widespread and highly contagious disease caused by Avian infectious bronchitis virus(IBV). Class Ⅱanimal diseases that can cause significant economic damage to poultry farming. In terms of genetic variation, like other RNA viruses, it is a unique nested transcription mode, and the discontinuity of the viral genome and the incomplete proofreading of RNA polymerase in the replication process result in the easy replacement, deletion and insertion of bases in the replication process, which further results in the high mutagenicity of the virus. However, in recent years, a number of studies have shown that the main cause of IBV mutation is not point mutation, but the genetic recombination caused by vaccine abuse and blind immunity. Under the dual influence of natural selection and external high-intensity immune pressure, IBV constantly evolves and mutates to produce new strong strains. this paper will maily introduce the prevalence of IBV in recent years around the world, deeply analyze the genetic evolution of IBV, and provide reliable data support for vaccine prevention and control of the disease.更多还原