ACE2 and COVID-19: SARS-CoV-2 viral particles have been found in the frontal lobe and cerebrospinal fluid (CSF) of COVID-19 patients,3,7 and SARS-CoV-2 replication can be detectable in the brains of human angiotensin-converting enzyme 2 (hACE2) knock-in mice.8–10 These evidences implicate that SARS-CoV-2 potentially invades the central nervous system (CNS) of COVID-19 patients and causes the neurological complications.