AUTHOR=Zhang Cheng , Cui Huan , Zhang Wuchao , Meng Lijia , Chen Ligong , Wang Zhongyi , Zhao Kui , Chen Zhaoliang , Qiao Sina , Liu Juxiang , Guo Zhendong , Dong Shishan 

TITLE=Epidemiological Investigation of Porcine Pseudorabies Virus in Hebei Province, China, 2017–2018

JOURNAL=Frontiers in Veterinary Science

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2022.930871

DOI=10.3389/fvets.2022.930871

ISSN=2297-1769

ABSTRACT=Pseudorabies (PR) is a serious disease affecting the pig industry in China. Therefore, it is very important to understand the epidemiology of pseudorabies virus (PRV). In the present study, 693 clinical samples were collected from Bartha-K61 vaccinated pigs with symptoms of suspected PRV infection between January 2017 and December 2018. All cases were referred for full clinical autopsy with detailed examination of histological examination, virus isolation and genetic evolution analysis of the PRV glycoprotein E (gE) gene. In addition, PRV gE antibodies in 3449 serum samples were detected by the enzyme-linked immunosorbent assay (ELISA). The results showed that abortion and stillbirth are the most frequent appearance in pregnant sows of these cases. Histopathological examination revealed lobar pneumonia, hepatitis, lymphadenitis, nephritis, and typical nonsuppurative encephalitis. A total of 248 cases tested were positive for the PRV gE gene by the PCR tests. Eleven PRV variants were isolated and confirmed by gE gene sequencing and phylogenetic analysis. These strains had 97.1%-100.0% nucleotide homology with the PRV reference strains. Notably, the isolated strains showed highly homologous and clustered in the same branch with HSD-1/2019, which causes human acute encephalitis. Serological tests showed that the positive rate of PRV gE antibody in the 3449 serum samples collected from the Hebei Province was 46.27%. In conclusion, PRV variant strains are high prevalence in the Hebei Province, which not only causes huge economic losses to the breeding industry but also potentially poses a threat to public health.