Mechanisms and implications of COVID-19 transport into neural tissue

ABSTRACT

The neuropathogenicity of COVID-19 was reported shortly after detection of the virus when patients began reporting symptoms of diminished taste and smell, headaches, mental status changes, and more. As the virus spread, increasing data on viral symptoms in conjunction with novel theories on COVID-19 virulence factors indicated that the virus had neurotropic properties. Several mechanisms have been proposed detailing severe acute respiratory syndrome coronavirus disease 2019 (SARS-CoV-2) transport past the blood–brain barrier and into neural tissue. This chapter offers a comprehensive review of possible neurotropic mechanisms including transport via the angiotensin-converting enzyme 2 (ACE-2) receptor, transportation directly past or through the blood–brain barrier, transsynaptic neuronal transfer, and olfactory conduction. © 2023 Elsevier Inc. All rights reserved.