2023年至2024年中国传染性法氏囊病病毒（IBDV）的流行病学特征：变异超强毒IBDV（mvvIBDV）与非典型传染性法氏囊病有关。

Epidemiological characteristics of infectious bursal disease virus (IBDV) in China from 2023 to 2024: Mutated very virulent IBDV (mvvIBDV) is associated with atypical IBD.

作者信息

Yu Hangbo, Wang Guodong, Zhang Wenying, Wu Ziwen, Niu Xinxin, Huang Mengmeng, Zhang Yulong, Liu Runhang, Han Jinze, Xu Mengmeng, Han Jingzhe, Ling Dan, Ke Erjing, Wang Suyan, Cui Hongyu, Zhang Yanping, Chen Yuntong, Liu Yongzhen, Duan Yulu, Gao Yulong, Qi Xiaole

机构信息

Avian Immunosuppressive Diseases Division, State Key Laboratory for Animal Disease Control and Prevention, Harbin Veterinary Research Institute, the Chinese Academy of Agricultural Sciences, Harbin, 150069, China; WOAH Reference Laboratory for Infectious Bursal Disease, Harbin Veterinary Research Institute, the Chinese Academy of Agricultural Sciences, Harbin, 150069, China.

出版信息

Poult Sci. 2025 Jul;104(7):105195. doi: 10.1016/j.psj.2025.105195. Epub 2025 Apr 21.

DOI:10.1016/j.psj.2025.105195

PMID:40328040

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC12124611/

Abstract

Infectious bursal disease (IBD), caused by the infectious bursal disease virus (IBDV), threatens the global poultry industry with acute immunosuppression. The non-lethal novel variant IBDV (nVarIBDV) has been identified as the primary cause of a new outbreak of atypical IBD in China. However, since 2023, several poultry farms in China have continuously reported the detection of vvIBDV in chicken flocks exhibiting atypical IBD characteristics. To analyze this abnormal problem, the prevalence of IBDV in major poultry farming areas in China from 2023 to 2024 was monitored. Our epidemiological survey revealed four coexisting IBDV strains in China, nVarIBDV (69.9 %, 65/93) ranked the first, followed by vvIBDV (16.1 %, 15/93), attIBDV (8.6 %, 8/93), and cIBDV (5.4 %, 5/93). Notably, all these 15 vvIBDV strains detected in this study harbored single or combination mutations in the VP2 hypervariable region (HVR) including residue 279: D279N (seven strains), G254D/I256L/D279N (one strain), or A222T/G254D/I256L/D279N (seven strains). Furthermore, one representative strain of IBDV-NMG23-1701 which contained the D279N mutation was isolated. In the phylogenetic tree constructed based on the IBDV genome, IBDV-NMG23-1701 was located in the vvIBDV branch. However, IBDV-NMG23-1701 did not kill chickens directly but induced severe subclinical symptoms of atypical IBD. We named these strains mutated vvIBDV (mvvIBDV), which genotypically belonged to vvIBDV but exhibited atypical IBD symptoms. The mvvIBDV has been detected in several major poultry farming areas in China. This is the first study to identify mvvIBDV as a new pathogen causing atypical IBD, providing a scientific basis for optimizing prevention and control strategies.

摘要

传染性法氏囊病（IBD）由传染性法氏囊病病毒（IBDV）引起，以急性免疫抑制威胁全球家禽业。非致死性新型变异IBDV（nVarIBDV）已被确定为中国非典型IBD新疫情的主要病因。然而，自2023年以来，中国几家家禽养殖场不断报告在表现出非典型IBD特征的鸡群中检测到vvIBDV。为分析这一异常问题，监测了2023年至2024年中国主要家禽养殖地区IBDV的流行情况。我们的流行病学调查显示，中国存在四种共存的IBDV毒株，nVarIBDV（69.9%，65/93）排名第一，其次是vvIBDV（16.1%，15/93）、attIBDV（8.6%，8/93）和cIBDV（5.4%，5/93）。值得注意的是，本研究中检测到的所有这15株vvIBDV毒株在VP2高变区（HVR）存在单个或组合突变，包括279位氨基酸：D279N（7株）、G254D/I256L/D279N（1株）或A222T/G254D/I256L/D279N（7株）。此外，分离出一株含有D279N突变的IBDV代表性毒株IBDV-NMG23-1701。在基于IBDV基因组构建的系统发育树中，IBDV-NMG23-1701位于vvIBDV分支。然而，IBDV-NMG23-1701不会直接导致鸡死亡，但会引发严重的非典型IBD亚临床症状。我们将这些毒株命名为突变vvIBDV（mvvIBDV），其基因型属于vvIBDV，但表现出非典型IBD症状。mvvIBDV已在中国几个主要家禽养殖地区被检测到。这是首次将mvvIBDV鉴定为导致非典型IBD的新病原体的研究，为优化防控策略提供了科学依据。