No evidence has been found that the neurological damages or complications following an infection by SARS-CoV-2 can be attributed to the proliferation of the virus itself. Mice inoculated in the nasal cavity by an adenovirus with the S1 segment show olfactory lesions, malaise, depression and inflammation of the brain. An elevation in intracellular calcium level correlates with the presence of Spike1 (S1) protein as well. The cholinergic anti-inflammatory pathway (CAP) was discovered as a mechanism for suppressing inflammation in peripheral tissues. S1 protein disrupts the CAP and reduce the amount of acetylcholine thus preventing a downregulation of inflammatory cytokine. Preventing breakdown of acetylcholine reversed inflammation while fatigue and depressive clinical signs disappeared.