Origin, Evolution, and Virulence of Porcine Deltacoronaviruses in the United States

Ma, Yuanmei; Zhang, Yu; Liang, Xueya; Lou, Fangfei; Oglesbee, Michael; Krakowka, Steven; Li, Jianrong

Histological changes in gnotobiotic piglets infected with the PdCV CVM1 or MI strain. Twenty-four hours after challenge with PdCV Ohio CVM1, severe villous atrophy of the duodenum, jejunum, and ileum was apparent (Fig. 3A) . The villous changes were associated with extensive intestinal epithelial degeneration and necrosis. No intestinal lesions were found in uninfected piglets (Fig. 3B ). In addition, focal areas of gastric epithelial cell degeneration and necrosis were observed in the gastric pits within the cardia, greater curvature of the fundus, and antrum of the stomach (Fig. 3D) . No lesions were found in the stomachs of un-infected piglets (Fig. 3C ). Epithelial cell necrosis was occasionally accompanied by syncytial giant cell formation in the gastric glandular mucosa, duodenum, jejunum, and ileum. Aside from edema of the lamina propria, the mucosal epithelial lining cells of the cecum and spiral colon were unchanged. No significant lesions were observed in extraintestinal tissues at this time.