However, during SARS-CoV and SARS-CoV-2 infection, when receptor ACE2 is bound by the viral spike protein, ACE2 function is disrupted, leading to the activation of MAPKs, the production of proinflammatory cytokines and the pathogenesis of pneumonia or even ARDS [227–232]. Here, ACE2 is linked to susceptibility to pneumonia measurement.