Department of Swine Diseases, National Veterinary Research Institute, Puławy, Poland.
Department of Biochemistry, National Veterinary Research Institute, Puławy, Poland.
PLoS One. 2021 Oct 29;16(10):e0258318. doi: 10.1371/journal.pone.0258318. eCollection 2021.
Porcine epidemic diarrhoea (PED) is a highly contagious enteric viral disease of pigs with a high morbidity and mortality rate, which ultimately results in huge economic losses in the pig production sector. The etiological agent of this disease is the porcine epidemic diarrhoea virus (PEDV) which is an enveloped, positive single-stranded RNA virus. The aim of this study was to perform molecular characterization of PEDV to identify the strains circulating in Poland. In this study, 662 faecal samples from 2015 to 2021 were tested with reverse transcription quantitative real-time PCR (RT-qPCR) and the results showed that 3.8% of the tested samples revealed a positive result for PEDV. A phylogenetic analysis of the complete genome and complete S gene sequences showed that Polish PEDV strains belonged to the G1b (S-INDEL) subgroup and were closely related to the European PEDV strains isolated from 2014 to 2019. Furthermore, RDP4 analysis revealed that the Polish PEDV strains harboured a recombinant fragment of ~400 nt in the 5' end of S gene with PEDV and swine enteric coronavirus (SeCoV) being the major and minor parents, respectively. Antigenic analysis showed that the aa sequences of neutralizing epitopes were conserved among the Polish PEDV strains. Only one strain, #0100/5P, had a unique substitution in the COE epitope. However, Polish PEDV strains showed several substitutions, especially in the COE antigen, as compared to the classical strain CV777. To the best of our knowledge, this is the first report concerning the molecular characterization of porcine epidemic diarrhoea virus strains, as well as the first phylogenetic analysis for PEDV in Poland.
猪流行性腹泻（PED）是一种高传染性的猪肠道病毒病，发病率和死亡率都很高，最终给养猪业造成巨大的经济损失。该病的病原体是猪流行性腹泻病毒（PEDV），它是一种有包膜的、正链单股 RNA 病毒。本研究旨在对 PEDV 进行分子特征分析，以确定在波兰流行的毒株。在这项研究中，使用反转录定量实时 PCR（RT-qPCR）对 2015 年至 2021 年的 662 份粪便样本进行了检测，结果显示 3.8%的检测样本 PEDV 呈阳性。对完整基因组和完整 S 基因序列的系统进化分析表明，波兰 PEDV 株属于 G1b（S-INDEL）亚群，与 2014 年至 2019 年从欧洲分离的 PEDV 株密切相关。此外，RDP4 分析显示，波兰 PEDV 株在 S 基因 5'端具有约 400nt 的重组片段，主要亲本为 PEDV，次要亲本为猪肠冠状病毒（SeCoV）。抗原分析表明，波兰 PEDV 株的中和表位 aa 序列在株间保守。只有一株，#0100/5P，在 COE 表位有一个独特的取代。然而，与经典株 CV777 相比，波兰 PEDV 株在 COE 抗原上表现出几个取代，特别是在 COE 抗原上。据我们所知，这是首次对猪流行性腹泻病毒株进行分子特征分析，也是首次对波兰的 PEDV 进行系统进化分析。
