there doesnt seem to be much coming out about xmrv, as a cause it seems like its going to slowly disappear due to other studies unable to find it. Seems to be going like hhv6 and valcyte, treating this has helped alot of people but also alot of non-reponders so cant be nailed down as a single cause of cfs. I really think in cfs somehow the immune system and some parts of the brain like the hypothalamus etc are broken by what ever infection people may have initially had, be it ebv, hhv6 or some bacterial infection, then we just tend to pick up opportunistic infections. I think thats why some of us have felt better after a course of antibiotics, antifungals etc. I have improved alot on antivirals, but still cant shake this insomnia which i think increases general aches and pains. I think something in my neurology(my sleep centre) has been permanently damaged by the viruses i had that caused my cfs. I think everyone with cfs seems to be affected slightly different, maybe due to different infections and severity. I just dont think they are going to nail it down to a single cause, chronic reactivated ebv seems to be the the most accurate finding, but so many others out there also where ebv hasnt troubled them. Who 'knows'?????????????