The Influence of Coronavirus Disease-2019 (COVID-19) On Parkinson's Disease: An Updated Systematic Review.

Background: COVID-19 has affected global communities with multiple neurological complications in addition to other critical medical issues. COVID-19 binds to the host's angiotensin-converting enzyme 2 (ACE2) receptors, which are expressed in the neurons and glial cells, acting as an entry port to the central nervous system (CNS). ACE2 receptors are abundantly expressed on dopamine neurons, which may worsen the prognosis of motor symptoms in Parkinson's disease (PD).