Wang Suchun, Pan Junhui, Zhou Kaiyutai, Chu Dianfeng, Li Jinji, Chen Yiping, Qi Qian, Wei Shimeng, Li Chao, Sui Jinyu, Wu Faxing, Li Jinping, Hou Guangyu, Liu Hualei, Wang Kaicheng
China Animal Health and Epidemiology Center, Qingdao, China.
Key Laboratory of Animal Biosafety Risk Prevention and Control (South), Ministry of Agriculture and Rural Affairs, Qingdao, China.
Front Microbiol. 2024 Oct 15;15:1456415. doi: 10.3389/fmicb.2024.1456415. eCollection 2024.
Infectious bronchitis virus (IBV) can cause serious harm to poultry industry. It is belong to Coronaviridae which is highly variable. A kind of emerging recombinant IBV (ahysx-1) has been detected in chicken from China in 2016. To understand the epidemiology and characterization of the emerging recombinant IBV, 35,455 samples of chickens from the 15 provinces in China were collected and detected. One hundred and ninety-six out of the 537 flocks (positive rate, 36.49%), and 908 out of 35,455 samples (positive rate, 2.56%) were positive in the detection. The results showed that the emerging recombinant IBV was pandemic in China. Thirteen emerging recombinant IBV isolates were selected and continuous subcultured to the fourth generation and analyzed by Next-generation sequencing. Compared with the reported sequence of ahysx-1, the genomic analysis showed that multiple position insertions and deletions were in 1a gene, 3b gene, M gene and N gene. The identity of the gene nucleotide sequence between all the 13 emerging recombinant IBV isolates and reference stain ahysx-1 were 98.1-99.1%, while the identity of amino acid sequence were 98.0-99.8%. To better understand the recombination mechanism of the emerging recombinant IBV, the genomic sequence of the 13 isolates were compared with turkey coronavirus or guinea fowl coronavirus. The results suggest that all the 13 emerging recombinant IBV isolates were likely to be the recombination of turkey coronavirus or guinea fowl coronavirus with IBV. Turkey coronavirus or guinea fowl coronavirus as minor parents are the donors of S gene. The major parents donors of the genome backone of these recombination events were lineages GI-19 or GVI-1 of IBV. One isolate (IBV/chicken/Henan/H1173/2021) was selected for pathogenicity analysis. The results showed that IBV/chicken/Henan/H1173/2021 was avirulent to SPF embryonated eggs, but could cause intestinal symptoms in of chicks. This study provides a foundation for understanding the epidemic situation and characterization of the emerging recombinant IBV. It is of great significance for the prevention and control of avian coronavirus infection.
传染性支气管炎病毒（IBV）可对家禽业造成严重危害。它属于高度可变的冠状病毒科。2016年在中国鸡群中检测到一种新型重组IBV（ahysx - 1）。为了解新型重组IBV的流行病学和特征，收集并检测了来自中国15个省份的35455份鸡样本。在537个鸡群中有196个呈阳性（阳性率为36.49%），在35455份样本中有908个呈阳性（阳性率为2.56%）。结果表明新型重组IBV在中国呈大流行状态。选取13株新型重组IBV分离株并连续传代至第四代，通过二代测序进行分析。与报道的ahysx - 1序列相比，基因组分析表明在1a基因、3b基因、M基因和N基因中存在多个位置的插入和缺失。13株新型重组IBV分离株与参考毒株ahysx - 1的基因核苷酸序列同一性为98.1 - 99.1%，而氨基酸序列同一性为98.0 - 99.8%。为更好地了解新型重组IBV的重组机制，将13株分离株的基因组序列与火鸡冠状病毒或珍珠鸡冠状病毒进行比较。结果表明，13株新型重组IBV分离株均可能是火鸡冠状病毒或珍珠鸡冠状病毒与IBV的重组体。火鸡冠状病毒或珍珠鸡冠状病毒作为次要亲本是S基因的供体。这些重组事件基因组骨架的主要亲本供体是IBV的GI - 19或GVI - 1谱系。选取一株分离株（IBV/鸡/河南/H1173/2021）进行致病性分析。结果表明，IBV/鸡/河南/H1173/2021对SPF胚蛋无毒力，但可引起雏鸡肠道症状。本研究为了解新型重组IBV的流行情况和特征提供了依据。对禽冠状病毒感染的防控具有重要意义。
