Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, 1600 S. 16th Street, Ames, IA 50011, USA.
Anim Health Res Rev. 2010 Dec;11(2):217-34. doi: 10.1017/S1466252310000162.
Porcine circovirus type 2 (PCV2) is a small, non-enveloped, circular, single-stranded DNA virus of economic importance in the swine industry worldwide. Based on the sequence analyses of PCV2 strains, isolates can be divided into five subtypes (PCV2a-e). PCV2 is an ubiquitous virus based on serological and viremia data from countries worldwide. In addition, PCV2 DNA was discovered in archived samples prior to the first recognition of clinical disease. Recently, a worldwide shift in PCV2 subtype from PCV2a to PCV2b occurred. PCV2 DNA can be detected in fecal, nasal, oral and tonsillar swabs as well as in urine and feces from both naturally and experimentally infected pigs. PCV2 DNA can be detected early in the infectious process and persists for extended periods of time. The effectiveness of disinfectants for reducing PCV2 in vitro is variable and PCV2 is very stable in the pig environment. Limited data exist on the horizontal transmission of PCV2. Direct transmission of PCV2 between experimentally or naturally infected animals and naïve animals has been documented and the incorporation of clinical or subclinically infected animals into a population represents a risk to the herd. Indirect transmission through the oral, aerosol or vaccine routes is likely a lesser risk for the transmission of PCV2 in most swine populations but may be worth evaluating in high heath herds. The objective of this review was to discuss data on the epidemiology and horizontal transmission of PCV2.
猪圆环病毒 2 型（PCV2）是一种具有经济重要性的小型、无包膜、环状、单链 DNA 病毒，在全球范围内的养猪业中广泛存在。根据 PCV2 毒株的序列分析，分离株可分为 5 个亚型（PCV2a-e）。基于来自全球各国的血清学和病毒血症数据，PCV2 是一种普遍存在的病毒。此外，在首次发现临床疾病之前，在存档样本中就发现了 PCV2 DNA。最近，PCV2 亚型在全球范围内从 PCV2a 向 PCV2b 发生了转变。PCV2 DNA 可在粪便、鼻腔、口腔和扁桃体拭子以及自然和实验感染猪的尿液和粪便中检测到。PCV2 DNA 可在感染过程的早期检测到，并持续较长时间。消毒剂对体外降低 PCV2 的效果各不相同，而 PCV2 在猪环境中非常稳定。关于 PCV2 水平传播的数据有限。已记录到 PCV2 在实验或自然感染动物与无感染动物之间的直接传播，将临床或亚临床感染动物纳入群体代表着对畜群的风险。通过口服、气溶胶或疫苗途径的间接传播可能是大多数猪群中 PCV2 传播的较小风险，但在高健康畜群中可能值得评估。本综述的目的是讨论关于 PCV2 的流行病学和水平传播的数据。
