Gastrointestinal Manifestations of SARS-CoV-2: Transmission, Pathogenesis, Immunomodulation, Microflora Dysbiosis, and Clinical Implications.

The clinical manifestation of COVID-19, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in the respiratory system of humans is widely recognized. There is increasing evidence suggesting that SARS-CoV-2 possesses the capability to invade the gastrointestinal (GI) system, leading to the manifestation of symptoms such as vomiting, diarrhea, abdominal pain, and GI lesions. These symptoms subsequently contribute to the development of gastroenteritis and inflammatory bowel disease (IBD).

Animal models for SARS-CoV-2 and SARS-CoV-1 pathogenesis, transmission and therapeutic evaluation.

There is a critical need to develop animal models to alleviate vaccine and drug development difficulties against zoonotic viral infections. The coronavirus family, which includes severe acute respiratory syndrome coronavirus 1 and severe acute respiratory syndrome coronavirus 2, crossed the species barrier and infected humans, causing a global outbreak in the 21 century. Because humans do not have pre-existing immunity against these viral infections and with ethics governing clinical trials, animal models are therefore being used in clinical studies to facilitate drug discovery and testing efficacy of vaccines.