These are based on a number of common clinical and pathological features shared including hyposmia, pathology in the basal ganglia of one SARS-CoV-2 infected patient [168], and the activation of microglia mediated via pro-inflammatory cytokines (such as, IL-1β, TNF-α) release, which may then increase the risk for PD and the potential of protein aggregation due to disregulation of protein homeostasis [169]. This evidence concerns the gene TNF and Parkinson disease.