Yunnan Tropical and Subtropical Animal Virus Diseases Laboratory, Yunnan Animal Science & Veterinary Institute, Kunming 650224, China.
Yunnan Sino-Science Gene Technology Co., Ltd., Kunming 650501, China.
Viruses. 2022 Apr 25;14(5):895. doi: 10.3390/v14050895.
In recent years, the prevalence of pseudorabies virus (PRV) has caused huge economic losses to the Chinese pig industry. Meanwhile, PRV infection in humans also sounded the alarm about its cross-species transmission from pigs to humans. To study the regional PRV epidemic, serological and epidemiological investigations of PRV in pig populations from Yunnan Province during 2017-2021 were performed. The results showed that 31.37% (6324/20,158, 95% CI 30.73-32.01) of serum samples were positive for PRV glycoprotein E (gE)-specific antibodies via enzyme-linked immunosorbent assay (ELISA). The risk factors, including the breeding scale and development stage, were significantly associated with PRV seroprevalence among pigs in Yunnan Province. Of the 416 tissue samples collected from PRV-suspected pigs in Yunnan Province, 43 (10.33%, 95% CI 7.41-13.26) samples were positive for PRV- nucleic acid in which 15 novel PRV strains from these PRV-positive samples were isolated, whose and sequences were analyzed. Phylogenetic analysis showed that all 15 isolates obtained in this study belonged to the genotype II. Additionally, the gene of one isolate (YuN-YL-2017) was genetically closer to variant PRV strains compared with others, while the gene was in the same clade with other classical PRV strains, indicating that this isolate might be a recombinant strain generated from the classical and variant strains. The results revealed the severe PRV epidemic in Yunnan Province and indicated that PRV variants are the major genotypes threatening the pig industry development.
近年来，伪狂犬病病毒（PRV）的流行给中国养猪业造成了巨大的经济损失。同时，PRV 感染人类也敲响了其从猪向人类跨种传播的警钟。为研究该地区 PRV 的流行情况，对云南省 2017-2021 年猪群进行了 PRV 血清学和流行病学调查。结果显示，酶联免疫吸附试验（ELISA）检测到 31.37%（6324/20158，95%置信区间 30.73-32.01）的血清样本抗 PRV 糖蛋白 E（gE）特异性抗体阳性。包括养殖规模和发展阶段在内的风险因素与云南省猪 PRV 血清阳性率显著相关。从云南省疑似 PRV 猪采集的 416 份组织样本中，43 份（10.33%，95%置信区间 7.41-13.26）样本 PRV 核酸阳性，从这些 PRV 阳性样本中分离出 15 株新型 PRV 毒株，对其 和 序列进行了分析。系统进化分析显示，本研究获得的 15 个分离株均属于基因型 II。此外，一个分离株（YuN-YL-2017）的 基因与其他分离株相比，与变异型 PRV 株更为接近，而 基因与其他经典 PRV 株处于同一分支，表明该分离株可能是由经典株和变异株重组产生的重组株。研究结果揭示了云南省严重的 PRV 流行情况，表明变异型 PRV 是威胁养猪业发展的主要基因型。
