Porcine respiratory coronavirus in 10 provinces of China: Molecular epidemiology, genetic diversity, and pathogenesis of the isolated PRCV/NM strain.

Respiratory coronaviruses pose significant health threats to both humans and animals. Porcine respiratory coronavirus (PRCV) typically causes mild respiratory infections in pigs and serves as a valuable model for human respiratory coronavirus. However, the investigation of PRCV pathogenesis remains limited. This study investigates the prevalence, genetic diversity, and pathogenesis of PRCV in China. From 2022 to 2024, 1186 pig tracheal samples were collected across 10 provinces, revealing a widespread presence of PRCV with an 11.8 % overall prevalence. For the first time, we isolated a PRCV strain from China, designated PRCV/NM, which is closely related to American lineages. Notably, PRCV/NM demonstrated a strong tropism for respiratory epithelial cells and organoids, with no significant infection of intestinal tissues. Experimental infections in piglets revealed that PRCV/NM induces asymptomatic infections, accompanied by minimal pulmonary pathology and no intestinal involvement. Our study provides insights into the molecular epidemiology and pathogenesis of PRCV in China.