TMPRSS2 and COVID-19: Analyzing datasets shows that angiotensin converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2), which are key genes for COVID-19 virus entry, are not expressed in olfactory sensory cells, instead are expressed in epithelial support cells and stem cells, so smell sense change does not accompany with rhinitis symptoms [39, 40].