Work

Pathogenicity and antigenic characterization of a novel highly virulent lineage 3 porcine reproductive and respiratory syndrome virus 2

Year: 2024

Type: article

Abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) is a pathogen with a negative economic impact on the global swine industry. In 2019, a suspected highly pathogenic strain, NPUST-108-929/2019 (108–929), was isolated from a pig farm in Pingtung with an outbreak of high mortality and analyzed. The characteristics of PRRSV 108–929 have barely been studied. This study was to evaluate pathogenicity through animal challenge experiments using PRRSV 108–929 and antigenic characterization of this novel PRRSV. This PRRSV strain is PRRSV 2, belonging to lineage 3 based on open reading frame 5 sequence analysis. Four putative N-linked glycosylation sites (N32, N35, N44 and N51) are located on glycoprotein 5. Experimental results revealed that high fever occurred at 3 days postinoculation (dpi) in the high-titer inoculation (HIN) group (2 × 10 4 TCID 50 /mL), 8 dpi in the high-titer contact (HC) group, 4 dpi in the low-titer inoculation (LIN) group (2 × 10 3 TCID 50 /mL) and 9 dpi in the low-titer contact (LC) group. All pigs in each PRRSV 108–929 challenge and contact group showed severe clinical signs, such as high fever (>40.5 °C) and significant weight loss. Deaths occurred only in the HIN group; the survival rate was 60 %. All the piglets except the control group piglets showed high viremia titers (6.04–8.28 log 10 copies/μL). The pathogenic characteristics of PRRSV 108–929 suggest that it is a highly virulent PRRSV strain at both the farm and laboratory levels.

Source: Journal of Microbiology Immunology and Infection

DOI: 10.1016/j.jmii.2024.12.003