Shi Yuwen, Shi Kaichuang, Yin Yanwen, Feng Shuping, Long Feng, Lu Wenjun, Qu Sujie, Ma Yan, He Jiakang
Guangxi Key Laboratory of Animal Breeding, Disease Control and Prevention, College of Animal Science and Technology, Guangxi University, Nanning, China.
Nanning Kedi Biotechnology Co., Ltd, Nanning, China.
Front Microbiol. 2025 Jul 10;16:1625343. doi: 10.3389/fmicb.2025.1625343. eCollection 2025.
Porcine respiratory coronavirus (PRCV) is an important coronavirus to cause respiratory syndrome in pigs. To analyze the genetic and evolutional characteristics of PRCV in Guangxi province, southern China, a total of 6,267 clinical samples were collected from different pig farms, harmless treatment plants and abattoirs in Guangxi province during 2022-2024. Seventeen positive samples of PRCV were selected to amplify and analyze the S, M, and N gene sequences. The results showed that the positivity rate of PRCV was 1.13% (71/6,267) using RT-qPCR. The homology analysis revealed that the nucleotide (amino acid) identity were 98.2-100% (96.6-100%) among the obtained 17 S, M, and N gene sequences, and 91.3-98.1% (88.8-98.0%) among the obtained strains and the reference strains from different countries. The phylogenetic analysis indicated that all PRCV strains could be divided into two groups, tentatively designated group I and group II, and each group was further divided into different clades. The strains obtained from Guangxi province distributed in group I, and formed an independent clade. They were most closely related to PRCV 137 isolate 86/135308 strain from the United Kingdom basing on the S, M, and N gene sequences. The sequence analysis revealed that all PRCV strains from Guangxi province obtained in this study showed 672 nt/224 aa deletion in the 5' region of S gene, and there existed 37 amino acid mutations in different regions in S gene of different PCRV strains. Recombination analysis of S gene sequences did not find any recombination event. The Bayesian analysis indicated that all PRCV strains could be divided into Group I and II, and the obtained Guangxi strains belonged to group I. The population size of circulating PRCV strains kept slightly upward trend since its discovery in 1984 until 2010, showed a steady downward trend until 2020, and then a slight increase. The results suggested that the PRCV strains circulating in Guangxi province originated from Europe, and have evolved independently with genetic diversity. These findings enriched the epidemiological data of PRCV, and provided new information on the prevalence and genetic evolution of PRCV in Guangxi province of China.
猪呼吸道冠状病毒（PRCV）是引起猪呼吸道综合征的一种重要冠状病毒。为分析中国南方广西省PRCV的遗传和进化特征，2022年至2024年期间，从广西省不同猪场、无害化处理厂和屠宰场共采集了6267份临床样本。选取17份PRCV阳性样本对S、M和N基因序列进行扩增和分析。结果显示，使用RT-qPCR检测PRCV的阳性率为1.13%（71/6267）。同源性分析表明，所获得的17条S、M和N基因序列之间的核苷酸（氨基酸）同一性为98.2% - 100%（96.6% - 100%），所获得的毒株与来自不同国家的参考毒株之间的同一性为91.3% - 98.1%（88.8% - 98.0%）。系统发育分析表明，所有PRCV毒株可分为两组，暂定为I组和II组，每组又进一步分为不同的进化枝。从广西省获得的毒株分布在I组，并形成一个独立的进化枝。基于S、M和N基因序列，它们与来自英国的PRCV 137分离株86/135308毒株关系最为密切。序列分析表明，本研究中从广西省获得的所有PRCV毒株在S基因的5'区域均显示672 nt/224 aa缺失，并且不同PRCV毒株的S基因不同区域存在37个氨基酸突变。S基因序列的重组分析未发现任何重组事件。贝叶斯分析表明，所有PRCV毒株可分为I组和II组，所获得的广西毒株属于I组。自1984年发现以来，PRCV流行毒株的种群规模在2010年之前呈轻微上升趋势，到2020年呈稳定下降趋势，然后略有增加。结果表明，在广西省流行的PRCV毒株起源于欧洲，并已独立进化且具有遗传多样性。这些发现丰富了PRCV的流行病学数据，并为中国广西省PRCV的流行情况和遗传进化提供了新信息。
