Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice, Eastern Cape Province, 5700, South Africa.
SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Private Bag X1314, Alice, Eastern Cape Province, 5700, South Africa.
BMC Microbiol. 2017 Nov 2;17(1):212. doi: 10.1186/s12866-017-1121-4.
Porcine circovirus type 2 (PCV2) remains the main causative viral pathogen of porcine circovirus-associated diseases (PCVAD) of great economic importance in pig industry globally. This present study aims at determining the occurrence of the viral pathogen in swine herds of the Province.
The data obtained revealed that 15.93% of the screened samples (54/339) from the swine herds of the studied areas were positive for PCV2; while the severity of occurrence of the viral pathogen as observed at farm level ranges from approximately 5.6 to 60% in the studied farms. The majority (15 out of 17 = 88%) of the analyzed sequences were found clustering with other PCV2b strains in the phylogenetic analysis. More interestingly, two other sequences obtained were also found clustering within PCV2d genogroup, which is presently another fast-spreading genotype with observable higher virulence in global swine herds.
This is the first report of PCV2 in swine herds of the Province and the first detection of PCV2b and PCV2d in South African swine herds. It follows the first reported case of PCV2a in an outbreak of porcine multisystemic wasting syndrome (PMWS) in Gauteng Province, South Africa more than one decade ago. This finding confirmed the presence of this all-important viral pathogen in pigs of the region; which could result in a serious outbreak of PCVAD and huge economic loss at the instances of triggering factors if no appropriate measures are taken to effectively curb its spread.
猪圆环病毒 2 型（PCV2）仍然是全球猪圆环病毒相关疾病（PCVAD）的主要致病病毒病原体，对养猪业具有重要的经济意义。本研究旨在确定该病毒病原体在该省猪群中的发生情况。
从研究地区猪群中采集的 339 份样本中，有 15.93%（54/339）的样本检测为 PCV2 阳性；而在农场水平上观察到的病毒病原体的严重程度在研究农场中约为 5.6%至 60%。在系统发育分析中，17 个分析序列中的大多数（15 个=88%）与其他 PCV2b 株聚类。更有趣的是，另外两个获得的序列也在 PCV2d 基因型内聚类，这是目前在全球猪群中传播速度较快且具有更高毒力的另一种基因型。
这是该省猪群中首次报告 PCV2，也是南非猪群中首次检测到 PCV2b 和 PCV2d。这是 10 多年前南非豪登省首例暴发猪多系统衰弱综合征（PMWS）时首次报告的 PCV2a 病例。这一发现证实了该重要病毒病原体在该地区猪群中的存在；如果不采取适当措施有效遏制其传播，该地区可能会暴发严重的 PCVAD，并在触发因素出现时造成巨大的经济损失。
