This olfactory-based infection pathway is backed by findings of SARS-CoV-2 RNA and distinctive coronavirus-associated substructures within nasal mucus and epithelial cells, as well as a colocalization analysis showing perinuclear S protein positivity within TuJ1+, NF200+, and OMP+ neural cells in the olfactory mucosa, indicating viral infection of olfactory neurons [45, 46]. This evidence concerns the gene PROS1 and viral infectious disease.