TH and susceptibility to pneumonia measurement: A neuropathological comparison of individuals who died from COVID‐19 versus pneumonia or respiratory failure identified SARS‐CoV‐2–immunoreactive neurons in the dorsal medulla and substantia nigra of Parkinson's disease patients, as well as tyrosine hydroxylase–positive neurites and viral RNA in these regions, suggesting possible viral antigen presence in dopaminergic neurons [53].