PDF(Pubmed)
Abstract：
Since 2013, the porcine reproductive and respiratory syndrome virus type 2 (PRRSV-2), lineage 1.8 (NADC30-like PRRSV) has emerged and become widely prevalent in China. The NADC30-like PRRSV poses significant challenges for disease control, primarily because of its propensity for frequent mutations and recombinations. We successfully isolated and identified a NADC30-like strain, designated SCCD22, in Chengdu, Sichuan Province, China. We meticulously examined the genetic recombination properties and evaluated its pathogenicity in 28-day-old piglets. SCCD22 showed 93.02% nucleotide homology with the NADC30 PRRSV strain, and its non-structural protein 2 coding region showed the same 131 amino acid deletion pattern as that seen in NADC30. Furthermore, we identified two recombination events in SCCD22: one in the NSP2 region (1,028-3,290 nt), where it was highly similar to the JXA1-like strain GZ106; and another in the NSP10 ~ 12 region (9,985-12,279 nt), closely resembling the NADC30-like strain CY2-1604. Piglets infected with SCCD22 exhibited clinical symptoms such as elevated body temperature, prolonged fever, reduced appetite, and roughened fur. Postmortem examinations underscored the typical lung pathology associated with PRRSV, indicating that the lungs were the primary affected organs. Furthermore, extended viral shedding accompanied by progressive viremia was observed in the serum and nasal excretions of infected piglets. In summary, this study reports a domestic PRRSV recombination strain in the Sichuan Province that can provide critical insights into preventing and controlling PRRSV in this region.
摘要：
自2013年以来，猪繁殖与呼吸综合征病毒2型（PRRSV-2），谱系1.8（NADC30样PRRSV）已经出现并在中国广泛流行。NADC30样PRRSV对疾病控制提出了重大挑战，主要是因为它倾向于频繁的突变和重组。我们成功分离并鉴定了一株NADC30样菌株，指定SCCD22，在成都，四川省,中国。我们精心检查了遗传重组特性，并评估了其在28日龄仔猪中的致病性。SCCD22与NADC30PRRSV株有93.02%的核苷酸同源性,其非结构蛋白2编码区显示与NADC30相同的131个氨基酸缺失模式。此外，我们在SCCD22中确定了两个重组事件：一个在NSP2区域（1,028-3,290nt），与JXA1样菌株GZ106高度相似；另一个在NSP10〜12区域（9,985-12,279nt），非常类似于NADC30样菌株CY2-1604。感染SCCD22的仔猪表现出体温升高等临床症状，长时间发烧,食欲降低,和粗糙的皮毛。尸检强调了与PRRSV相关的典型肺部病理，表明肺是主要受影响的器官。此外，在感染仔猪的血清和鼻腔排泄物中观察到病毒持续脱落并伴有进行性病毒血症。总之,本研究报道了四川省国内PRRSV重组株，可为该地区预防和控制PRRSV提供重要见解。
