Porcine Transmissible Gastroenteritis – NAVLE Study Guide

Overview and Clinical Importance

Transmissible Gastroenteritis (TGE) is an acute, highly contagious viral enteric disease of swine caused by Transmissible Gastroenteritis Virus (TGEV), a member of the genus Alphacoronavirus in the family Coronaviridae. The disease is characterized by severe vomiting, profuse watery diarrhea, and extremely high mortality rates approaching 100% in piglets less than 2 weeks of age.

TGE was first reported in the United States in 1946 and has since been documented worldwide. Although the prevalence has declined in recent decades due to cross-protective immunity from Porcine Respiratory Coronavirus (PRCV), TGE remains economically significant and continues to be reported in North America, Europe, and Asia. Understanding this disease is essential for NAVLE preparation as it represents a classic example of viral enteric disease with high exam relevance.

Etiology

Causative Agent

TGEV is a pleomorphic, enveloped virus containing a positive-sense, single-stranded RNA genome of approximately 28.5 kilobases. The virus belongs to the order Nidovirales, family Coronaviridae, and genus Alphacoronavirus. TGEV is antigenically related to feline infectious peritonitis virus (FIPV) and canine coronavirus (CCoV), which may serve as potential reservoirs.