predicted the rare expression of ACE2 and TMPRSS2 in the salivary glands and ducts of healthy volunteers; however, they subsequently found that receptors and SARS-CoV-2 infection were more frequent in the salivary glands and ducts during COVID-19 autopsy using in situ hybridization (Huang et al., 2021). Here, TMPRSS2 is linked to COVID-19.