We speculate that viral infection of lung epithelial cells may result in lytic death of these cells, followed by infection of endothelial cells of lung capillaries (dependent on the expression of ACE2) and the subsequent release of viral particles from dying endothelial cells into the circulation, where they can spread and infect endothelial cells of other vascular beds all over the organism. The gene discussed is ACE2; the disease is infection.