PDF(Pubmed)
Abstract：
Marek\'s disease (MD) is an important neoplastic disease caused by serotype 1 Marek\'s disease virus (MDV-1), which results in severe economic losses worldwide. Despite vaccination practices that have controlled the MD epidemic, current increasing MD-suspected cases indicate the persistent viral infections circulating among vaccinated chicken farms in many countries. However, the lack of available information about phylogeny and molecular characterization of circulating MDV-1 field strains in Taiwan reveals a potential risk in MD outbreaks. This study investigated the genetic characteristics of 18 MDV-1 strains obtained from 17 vaccinated chicken flocks in Taiwan between 2018 and 2020. Based on the sequences of the meq oncogene, the phylogenetic analysis demonstrated that the circulating Taiwanese MDV-1 field strains were predominantly in a single cluster that showed high similarity with strains from countries of the East Asian region. Because the strains were obtained from CVI988/Rispens vaccinated chicken flocks and the molecular characteristics of the Meq oncoprotein showed features like vvMDV and vv+MDV strains, the circulating Taiwanese MDV-1 field strains may have higher virulence compared with vvMDV pathotype. In conclusion, the data presented demonstrates the circulation of hypervirulent MDV-1 strains in Taiwan and highlights the importance of routine surveillance and precaution strategies in response to the emergence of enhanced virulent MDV-1.
摘要：
马立克氏病（MD）是由1型马立克氏病病毒（MDV-1）引起的一种重要的肿瘤性疾病，这在全球范围内造成了严重的经济损失。尽管接种疫苗控制了MD的流行，目前MD疑似病例不断增加,表明在许多国家接种疫苗的养鸡场中持续存在病毒感染.然而,缺乏有关台湾流行的MDV-1田间毒株的系统发育和分子特征的可用信息，这揭示了MD暴发的潜在风险。这项研究调查了2018年至2020年间从台湾17个接种疫苗的鸡群中获得的18株MDV-1株的遗传特征。根据meq癌基因的序列,系统发育分析表明，台湾流行的MDV-1田间菌株主要位于单个簇中，与东亚地区国家的菌株具有高度相似性。由于这些菌株是从CVI988/Rispens接种的鸡群中获得的，并且Meq癌蛋白的分子特征显示出vvMDV和vvMDV菌株等特征，与vvMDV致病型相比，流行的台湾MDV-1田间毒株可能具有更高的毒力。总之,所提供的数据显示了高毒力MDV-1株在台湾的流行,并强调了常规监测和预防策略对增强毒力MDV-1出现的重要性.
