This mini-review focuses on the mechanisms of how severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) affects the brain, with an emphasis on the role of the spike protein in patients with neurological symptoms. Following infection, patients with a history of neurological complications may be at a higher risk of developing long-term neurological conditions associated with the α-synuclein prion, such as Parkinson's disease and Lewy body dementia. Compelling evidence has been published to indicate that the spike protein, which is derived from SARS-CoV-2 and generated from the vaccines currently being employed, is not only able to cross the blood-brain barrier but may cause inflammation and/or blood clots in the brain. Consequently, should vaccine-induced expression of spike proteins not be limited to the site of injection and draining lymph nodes there is the potential of long-term implications following inoculation that may be identical to that of patients exhibiting neurological complications after being infected with SARS-CoV-2. However, further studies are needed before definitive conclusions can be made.
Keywords: Lewy body dementia; Parkinson’s disease; angiotensin-converting enzyme 2 (ACE2); blood–brain barrier (BBB); cytokines; good laboratory practice; novel coronavirus disease that emerged in 2019 (COVID-19); severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2); spike protein.