Department of Pathology, University of Veterinary Medicine, István Str. 2., 1078 Budapest, Hungary.
CEVA-Phylaxia (Ceva Sante Animale), 1107 Budapest, Hungary.
Viruses. 2022 Jun 3;14(6):1219. doi: 10.3390/v14061219.
Porcine circovirus type 3 (PCV3) is an emerging pathogen that has been reported worldwide in all ages of healthy and clinically ill pigs. The presence of this virus in Hungary has been confirmed in a commercial farm experiencing reproductive failures, but there were no data on the circulation of PCV3 in the country. Here we report the prevalence and the genetic diversity of PCV3 in Hungarian herds. To estimate the prevalence, 1855 serum samples, 176 oral fluid and 97 processing fluid samples were collected in a systematic, cross-sectional method from 20 large scale swineherds and tested by real-time qPCR. PCV3 was present in at least one type of diagnostic matrix in 19 out of the 20 (95%) pig farms. The highest detection rates were observed in the processing fluid samples (61%), but 41% of the oral fluid and 23% of the serum samples were positive. The virus was found in all age groups, and slightly more adult animals were infected than growing pigs, but the viral burden was lower amongst them. Phylogenetic analysis of nine complete genomes, obtained from either the sampled herds or organ samples of PCV3-positive carcasses, showed high nucleotide identity between the detected sequences, which all belonged to the PCV3a genotype. Our results indicate that PCV3 is widespread in Hungary, but in most cases, the virus seems to circulate subclinically, infecting all age groups and production phases without the presence of apparent clinical disease.
猪圆环病毒 3 型（PCV3）是一种新兴的病原体，已在全球所有年龄段的健康和临床患病猪中报道。该病毒在经历繁殖失败的商业农场中的存在已在匈牙利得到证实，但该国尚无 PCV3 循环的数据。在这里，我们报告了匈牙利畜群中 PCV3 的流行率和遗传多样性。为了估计流行率，我们采用系统的横断面方法从 20 个大型养猪场中收集了 1855 份血清样本、176 份口腔液样本和 97 份加工液样本，并通过实时 qPCR 进行了检测。在 20 个养猪场中的 19 个（95％）至少有一种诊断基质中存在 PCV3。在加工液样本中观察到最高的检测率（61％），但 41％的口腔液样本和 23％的血清样本为阳性。该病毒存在于所有年龄组中，成年动物的感染略多于生长猪，但它们的病毒载量较低。从采样畜群或 PCV3 阳性尸体的器官样本中获得的九个完整基因组的系统发育分析表明，检测到的序列之间具有很高的核苷酸同一性，均属于 PCV3a 基因型。我们的结果表明，PCV3 在匈牙利广泛传播，但在大多数情况下，该病毒似乎呈亚临床传播，感染所有年龄组和生产阶段，而没有明显的临床疾病。
