There is a possible link between Cold Sores and Alzheimer’s Disease. From what I read, the Herpes virus that causes cold sores which goes dormant appears to eventually move into the brain, and create what we know as Alzheimer’s Disease.
We all have a blood-brain barrier that stops almost all virus’ from entering the brain itself, but as we know, there are some brain issues that show some virus’ are able to make it through the brain-blood barrier and cause brain infections.
Here is a link from the most comprehensive article I stumbled across. There was another article commenting on this study, but I could not retrieve the link.
Personally, I hope this link proves to be false….