Plasma AngII levels in COVID-19 patients are markedly elevated and positively correlated with viral titers.53 Excessive AngII increases lung hydrostatic pressure and microvascular permeability, resulting in inflammatory cell infiltration, pulmonary edema and fibroblast proliferation.54–56 These findings suggest that ACE2 also plays a protective role in COVID-19. Here, ACE2 is linked to COVID-19.