The State Key Laboratory of Agricultural Microbiology, Huazhong Agriculture University, Wuhan 430070, China.
College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, China.
Viruses. 2021 Oct 27;13(11):2167. doi: 10.3390/v13112167.
Bovine leukaemia virus (BLV) is a deltaretrovirus that is closely related to human T-cell leukaemia virus types 1 and 2 (HTLV-1 and -2). It causes enzootic bovine leukosis (EBL), which is the most important neoplastic disease in cattle. Most BLV-infected cattle are asymptomatic, which potentiates extremely high shedding rates of the virus in many cattle populations. Approximately 30% of them show persistent lymphocytosis that has various clinical outcomes; only a small proportion of animals (less than 5%) exhibit signs of EBL. BLV causes major economic losses in the cattle industry, especially in dairy farms. Direct costs are due to a decrease in animal productivity and in cow longevity; indirect costs are caused by restrictions that are placed on the import of animals and animal products from infected areas. Most European regions have implemented an efficient eradication programme, yet BLV prevalence remains high worldwide. Control of the disease is not feasible because there is no effective vaccine against it. Therefore, detection and early diagnosis of the disease are essential in order to diminish its spreading and the economic losses it causes. This review comprises an overview of bovine leukosis, which highlights the epidemiology of the disease, diagnostic tests that are used and effective control strategies.
牛白血病病毒（BLV）是一种与人类 T 细胞白血病病毒 1 型和 2 型（HTLV-1 和 -2）密切相关的δ逆转录病毒。它引起地方性牛白血病（EBL），这是牛群中最重要的肿瘤性疾病。大多数 BLV 感染的牛无症状，这使得许多牛群中病毒的极高脱落率成为可能。约 30%的牛出现持续的淋巴细胞增多，具有各种临床结果；只有一小部分动物（不到 5%）表现出 EBL 的迹象。BLV 给奶牛业带来了重大的经济损失，特别是在奶牛场。直接成本是由于动物生产力和牛寿命下降所致；间接成本是由于对来自感染地区的动物和动物产品的进口限制造成的。大多数欧洲地区都实施了有效的根除计划，但 BLV 的流行率在全球仍然很高。由于没有针对该疾病的有效疫苗，因此控制该疾病是不可行的。因此，检测和早期诊断该疾病对于减少其传播和造成的经济损失至关重要。本综述包括对牛白血病的概述，突出了该疾病的流行病学、使用的诊断测试和有效的控制策略。
