Well, I hate to say this because it sounds ridiculous, arrogant, etc., but I think the folks at Mayo are wrong about anti-virals effects on latent EBV, latent HHV6 and latent CMV. Tell them to get on their computers and do a little research into the studies done by Jose Montoya at Stanford, where Valcyte gave most people with latent EBV a big improvement in symptoms. Also, even the recent studies with Rituximab show that going after viruses on the B lympocyte, where herpes viruses (EBV, HHV6 are herpes viruses) reside, cause people to improve.
I myself had no sign of active EBV infection when I got CFIDS. I had had EBV in highschool. I developed CFIDS in my 30's, after having septic shock, and I had normal bloodwork. I felt horrible, and the only thing wrong with my bloodwork is that my indicators for PAST EBV were through the roof. I had no indication of current EBV at that time. After I took anti-virals, my numbers on my blood work for past EBV infection came down from like 3000 to 300, and lo and behold, simultaneously, I achieved remission.
Also, to the previous poster, you HAVE infections/pathogens if you have CFIDS. However, sometimes infections don't show up in bloodwork, because platelets are over-active in CFIDS and the bacteria and platelets hide in the clumpy blood. I had to be on heparin for a year before my tests for HHV6 infection showed up positive. My doctor and I couldn't figure out why if my EBV had come down, I still felt bad, so I did the heparin to find out what else was there.
Also, what have you been tested for? There are alot of pathogens - EBV, HHV6, CMV, Babesia, other parasites, Chlamydia pneumonia, mycoplasm pneumonia, Lyme disease, and like 7 or 8 other pathogens.