Olfactory transmucosal SARS-CoV-2 invasion as a port of central nervous system entry in individuals with COVID-19

The newly identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, a pandemic respiratory disease. Moreover, thromboembolic events throughout the body, including in the CNS, have been described. Given the neurological symptoms observed in a large majority of individuals with COVID-19, SARS-CoV-2 penetrance of the CNS is likely. By various means, we demonstrate the presence of SARS-CoV-2 RNA and protein in anatomically distinct regions of the nasopharynx and brain. Furthermore, we describe the morphological changes associated with infection such as thromboembolic ischemic infarction of the CNS and present evidence of SARS-CoV-2 neurotropism. SARS-CoV-2 can enter the nervous system by crossing the neural-mucosal interface in olfactory mucosa, exploiting the close vicinity of olfactory mucosal, endothelial and nervous tissue, including delicate olfactory and sensory nerve endings. Subsequently, SARS-CoV-2 appears to follow neuroanatomical structures, penetrating defined neuroanatomical areas including the primary respiratory and cardiovascular control center in the medulla oblongata. The authors demonstrate the presence of SARS-CoV-2 in the nasopharynx and brain, suggesting that the virus is present in the CNS and may enter through the olfactory mucosa, exploiting the close vicinity of olfactory mucosal, endothelial and nervous tissue.

Automated summary

The study demonstrates the presence of SARS-CoV-2 in the nasopharynx and brain, suggesting the virus may enter the CNS through the olfactory mucosa. The virus utilizes the neural-mucosal interface in the olfactory mucosa to penetrate the nervous system, affecting various neuroanatomical areas, including the primary respiratory and cardiovascular control center.