08-15-2021-0105 - Prion Disease 2

 There exists evidence that prion diseases may be transmissible by the airborne route.^[14]

Note that not all encephalopathies are caused by prions, as in the cases of PML (caused by the JC virus), CADASIL (caused by abnormal NOTCH3 protein activity), and Krabbe disease (caused by a deficiency of the enzyme galactosylceramidase). Progressive Spongiform Leukoencephalopathy(PSL)—which is a spongiform encephalopathy—is also probably not caused by a prion, although the adulterant that causes it among heroin smokers has not yet been identified.^{[15][16][17][18]} This, combined with the highly variable nature of prion disease pathology, is why a prion disease cannot be diagnosed based solely on a patient's symptoms.

https://en.wikipedia.org/wiki/Transmissible_spongiform_encephalopathy#Genetics