TABLE 2.

Comparison of infection routes and clinical manifestations of the CNS and the PNS caused by coronaviruses.

Type	CNS				PNS
Route of infection	Neurons retrograde	Receptor binding	Olfactory system	Trojan horse mechanism	Direct destruction	Indirect destruction
Clinical manifestation	Headache, dizziness, cognitive impairment, acute cerebrovascular disease, epilepsy.		Reduced or even loss of smell and related neurological disorders.	Encephalitis, neuritis, and other inflammatory diseases of the nervous system.	Symptoms, Muscle atrophy, muscle weakness, loss of muscle reflexes, inability to move freely, and hypogeusia, neuralgia.	Guillain-Barre syndrome (GBS), facial and neuritis.