The link below is to a research project that links HSV-1 (the 'cold sore' herpes virus) to cholesterol accumulation:
Journal of Biological Chemistry
I would stress that I have not read the whole article. It is highly technical. The abstract at the start gives you the gist.
The reason for drawing attention to it here is that it is yet another example of this very common virus being implicated in the kind of damage to the body (in this case to 'hardening of the arteries') that could lead to dementia.
Regular readers of AWD will know that I have posted about herpes viruses a number of times. This link will take you to these posts.
I should stress again that I have no medical training and have made no 'discoveries' myself. Such research as I have undertaken has been via Google!