Veterinary Immunology Laboratory, College of Veterinary Medicine, Northwest Agriculture and Forestry University, Yangling, Shaanxi Province 712100, China.
Shenmu Animal Husbandry Development Center, Shenmu, Shaanxi Province 719399, China.
Virus Res. 2023 Sep;334:199160. doi: 10.1016/j.virusres.2023.199160. Epub 2023 Jul 5.
Contagious ecthyma (CE) is an acute infectious zoonosis caused by orf virus (ORFV) that mainly infects sheep and goats and causes obvious lesions and low market value of livestock, resulting in huge economic losses for farmers. In this study, two strains of ORFV were isolated from Shaanxi Province and Yunnan Province in China, named FX and LX. The two ORFVs were located in the major clades of domestic strains respectively, and exhibited distinct sequence homology. We analyzed the genetic data of core genes (B2L, F1L, VIR, ORF109) and variable genes (GIF, ORF125 and vIL-10) of ORFV to investigate its epidemiological and evolutionary characteristics. The sequences from 2007 to 2018 constituted the majority of the viral population, predominantly concentrated in India and China. Most genes were clustered into SA00-like type and IA82-like type, and the hotspots in East and South Asia were identified in the ORFV transmission trajectories. For these genes, VIR had the highest substitution rate of 4.85 × 10, both VIR and vIL-10 suffered the positive selection pressure during ORFV evolution. Many motifs associated with viral survival were distributed among ORFVs. In addition, some possible viral epitopes have been predicted, which still require validation in vivo and in vitro. This work gives more insight into the prevalence and phylogenetic relationships of existing orf viruses and facilitate better vaccine design.
传染性脓疱性皮炎（CE）是一种由羊口疮病毒（ORFV）引起的急性传染病，主要感染绵羊和山羊，导致家畜明显病变和市场价值降低，给农民造成巨大的经济损失。本研究从中国陕西和云南分离到两株 ORFV，分别命名为 FX 和 LX。两株 ORFV 分别位于国内株的主要分支中，表现出明显的序列同源性。我们分析了 ORFV 的核心基因（B2L、F1L、VIR、ORF109）和可变基因（GIF、ORF125 和 vIL-10）的遗传数据，以研究其流行病学和进化特征。2007 年至 2018 年的序列构成了病毒群体的大部分，主要集中在印度和中国。大多数基因聚类为 SA00 样型和 IA82 样型，在 ORFV 传播轨迹中确定了东亚和南亚的热点。对于这些基因，VIR 的替换率最高，为 4.85×10-3，VIR 和 vIL-10 在 ORFV 进化过程中都受到了正选择压力。ORFVs 中分布着许多与病毒存活相关的基序。此外，还预测了一些可能的病毒表位，但仍需要在体内和体外进行验证。这项工作更深入地了解了现有羊口疮病毒的流行情况和系统发育关系，有助于更好地设计疫苗。
