Our scRNAseq analysis also shows that ACE2 is expressed in small fractions of ciliated airway cells and epithelial cells of the nasal cavity (Figure 3A–B). While no staining is observed for ACE2 in nasopharynx samples from the Human Protein Atlas (HPA) IHC dataset (Figure 3—figure supplement 2), a previous IHC study did report the staining of ACE2 in nasal and oral mucosa and the nasopharynx (Hamming et al., 2004). This expression is consistent with the high SARS-CoV-2 viral loads detected in nasal swab samples (Wang et al., 2020c). Intriguingly, mild degeneration of olfactory epithelium was observed in an immunosuppressed animal model infected with SARS-CoV (Schaecher et al., 2008). These observations are correlated with emerging reports of anosmia/hyposmia (loss of smell) in otherwise asymptomatic COVID-19 patients (ENT UK, 2020). Such emerging clinical evidence emphasizes the need for further investigation into olfactory ACE2 expression via scRNAseq and other modalities.