So I thought this NPR story was interesting: Infectious Theory of Alzheimer's Disease Draws Fresh Interest
There re some statistical reasons to think something infectious could be involved, but it's certainly just another hypothesis at this point. There's one line of thought that Alzheimer's is come kind of late-life reactivation of the roseola virus - a rash that most babies get. For some reason the roseola virus shows up a lot in the brain tissue of Alzheimer's victims.
Could the dreaded disease
Have a connection
With a childhood rash
Or some other infection?