PDF(Pubmed)
Abstract：
Equid alphaherpesvirus 1 (EHV-1) is a ubiquitous and significant viral pathogen in horses worldwide, causing a range of conditions, including fever, respiratory disease, abortion in pregnant mares and the severe neurological disease called equine herpes myeloencephalopathy (EHM). Despite that EHV-1 is a notifiable animal disease in Sweden, there is limited knowledge about the circulating strains. This study aimed to analyze the genetic diversity of EHV-1 strains in equine samples from different Swedish outbreaks by partial genome sequencing. Genotyping based on three selected open reading frames ORF11, ORF30, and ORF34 in the viral genome was conducted for 55 outbreaks of EHV-1 spanning from the years 2012 to 2021. The analysis revealed 14 different genovariants, with one prominent genovariant identified in 49% of the outbreaks. Additionally, the study identified seven mutations not previously described. Three new mutations were demonstrated in ORF11, all synonymous, and four new mutations in ORF34, two synonymous, and two non-synonymous. Notably, different EHV-1 genovariants were found in five out of six studied EHM outbreaks, but clonal spreading was shown within the outbreaks. Moreover, the study demonstrated that healthy (recovered) horses that returned from an EHM outbreak at an international meeting in Valencia, Spain (2021), were positive for the virus clone responsible for the severe disease outbreak despite several weeks of quarantine. These findings shed light on the genetic diversity and transmission dynamics of the virus and significantly contribute to better understanding of the epidemiology of EHV-1 in Sweden and globally.
摘要：
马疱疹病毒1型(EHV-1)是全球马普遍存在的重要病毒病原体,造成一系列条件，包括发烧,呼吸道疾病,妊娠母马流产和严重的神经系统疾病称为马疱疹性脊髓脑病（EHM）。尽管EHV-1在瑞典是一种应报告的动物疾病，关于循环菌株的知识有限。本研究旨在通过部分基因组测序分析来自瑞典不同疫情的马样本中EHV-1菌株的遗传多样性。基于病毒基因组中三个选定的开放阅读框ORF11，ORF30和ORF34进行基因分型，对2012年至2021年的55次EHV-1暴发进行了。分析揭示了14种不同的基因变异，在49%的疫情中发现了一个突出的基因变异。此外,该研究发现了7个以前没有描述过的突变.在ORF11中证明了三个新的突变，都是同义词，以及ORF34中的四个新突变，两个同义词，和两个非同义词。值得注意的是,不同的EHV-1基因变异体在6次研究的EHM爆发中发现，但是在疫情中显示了克隆传播。此外，该研究表明，在瓦伦西亚的一次国际会议上，从EHM爆发中返回的健康（恢复）马匹，西班牙(2021),尽管隔离了几周，但导致严重疾病爆发的病毒克隆呈阳性。这些发现揭示了该病毒的遗传多样性和传播动态，并大大有助于更好地了解瑞典和全球的EHV-1流行病学。
