College of Life Sciences of Longyan University, Longyan 364012, China; College of Animal Science (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou 350002, China.
College of Life Sciences of Longyan University, Longyan 364012, China; Fujian Engineering Research Center for Swine Disease Control and Prevention, Longyan, Fujian 364012, China; Fujian Provincial Key Laboratory for the Prevention and Control of Animal Infectious Diseases and Biotechnology, Longyan, Fujian 364012, China.
Infect Genet Evol. 2023 Nov;115:105515. doi: 10.1016/j.meegid.2023.105515. Epub 2023 Oct 21.
Porcine parvovirus (PPV) is an important pathogen causing reproductive disorders in sows, with clinical symptoms including stillbirth, mummified fetuses, embryonic dysplasia and death, and sow infertility. Porcine parvovirus 7 (PPV7) is a recently discovered type of PPV and its widespread distribution and rapid evolution has caused huge economic losses in the pig industry. To investigate the molecular epidemiology of PPV7 in Fujian Province, China, we collected 491 blood samples and 72 tissue samples from diseased pigs in large-scale pig farms across selected areas of Fujian Province from 2019 to 2022. PPV7 infection was determined using real-time quantitative PCR, and positive samples underwent whole-genome amplification, sequencing, and subsequent homology, phylogenetic, and recombination analyses. The PPV7 positive detection rate was 25.73% (145/563) in Fujian Province, among which the positive rate of blood and tissue samples was 26.47% (130/491) and 20.83% (15/72), respectively. The nucleotide sequence homology among the 29 PPV7 whole-genome sequences obtained in this study was 90.0%-97.2%, whereas that with 128 reference strains from China and other countries was 88.9%-98.1%. Six strains had partial nucleotide deletions or insertions. Phylogenetic analysis based on the whole-genome sequences classified the 29 PPV7 strains and 128 reference strains into eight subtypes (PPV7a-PPV7h), and PPV7h was the predominant subtype in Fujian Province. Recombination analysis revealed evidence of inferred recombination events in the genomes of four strains. This study provides significant insights into the molecular characteristics of PPV7 in Fujian Province and serves as a crucial foundation for further advancements in PPV7 prevention and control strategies.
猪细小病毒 (PPV) 是一种重要的病原体，可引起母猪繁殖障碍，临床症状包括死胎、木乃伊化胎儿、胚胎畸形和死亡以及母猪不孕。猪细小病毒 7 型 (PPV7) 是一种新发现的 PPV 类型，其广泛分布和快速进化给养猪业造成了巨大的经济损失。为了调查中国福建省 PPV7 的分子流行病学，我们从 2019 年至 2022 年在福建省选定地区的大型养猪场采集了 491 份血样和 72 份组织样本，对患病猪进行了检测。采用实时定量 PCR 检测 PPV7 感染，对阳性样本进行全基因组扩增、测序，并进行同源性、系统进化和重组分析。在福建省，PPV7 的阳性检出率为 25.73%（145/563），其中血样和组织样的阳性率分别为 26.47%（130/491）和 20.83%（15/72）。本研究获得的 29 株 PPV7 全基因组序列之间的核苷酸序列同源性为 90.0%-97.2%，与来自中国和其他国家的 128 株参考株的同源性为 88.9%-98.1%。6 株有部分核苷酸缺失或插入。基于全基因组序列的系统进化分析将 29 株 PPV7 株和 128 株参考株分为 8 个亚型（PPV7a-PPV7h），其中 PPV7h 是福建省的主要流行亚型。重组分析表明，4 株的基因组中存在重组事件的证据。本研究为福建省 PPV7 的分子特征提供了重要信息，为进一步制定 PPV7 防控策略奠定了基础。
