Preliminary work suggests that human herpesviruses 6A and 7 have key roles in Alzheimer disease

Preliminary work suggests that human herpesviruses 6A and 7 have key roles in Alzheimer disease
https://www.jwatch.org/fw114301/2018/06/22/work-hints-herpesviruses-may-have-role-alzheimers

Human herpesviruses 6A and 7 have occasionally been mentioned in connection with ME/CFS.

Probably to get to the root of any connection with viruses you need biopsy work including on post-mortem samples. From what I have heard the UK ME charities don't have enough money to set up a post-mortem biobank.

 

This was picked up in NYT.

A Common Virus May Play Role in Alzheimer’s Disease, Study Finds

 

A number of recent studies have also found that Chlamydia Pneumonia may function as a "trigger or driver" for AD.