Figure 1. (A) Overview of human clinical manifestation of SARS-CoV-2 infection: showing common clinical features observed in hospitalized patients (98,99). Pneumonia, a major clinical feature in COVID-19 patients, complicated by ARDS leading to respiratory failure. Reports on human autopsies reported that the lung generally appeared congested and edematous, with different stages of diffuse alveolar damage characterized by fibrosis of the interstitium, desquamation of pneumocytes, hyaline membrane formation with inflammatory cell infiltration. In addition, direct assault to other organs by disseminated SARS-CoV-2 and immune pathogenesis were also observed such as cardiovascular complications, hypercoagulopathy, substantial reduction of lymphocytes, gastrointestinal dysfunction, and impaired liver function, and renal injury. (B) Overview of SARS-CoV-2 manifestations in different animal models. (created with BioRender.com).

ARDS, acute respiratory distress syndrome; TG, transgenic.