Figure 1.

Schematic representation showing the putative brain pathway of SARS-CoV2 in COVID-19. The virus enters the respiratory or olfactory epithelia of the nasal cavity, spreads (by trans-synaptic migration) to the brain through the olfactory or trigeminal tracts, and infects deeper parts of the brain, including respiratory centers in the thalamus, brain stem, and medulla. This leads to dysfunction of the respiratory centers, including Pre-Bötzinger complex, causing respiratory distress and hypoxaemia/hypoxia and leading to a strong stress response associated with sympathoexcitation. Dysfunction of the ANS triggers upregulation of VEGF and disruption of the BBB, further leading to the worsening of hypoxia, resulting in both acute and long-standing neurological symptoms.