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Dr Martin Pall on XMRV


Senior Member
XMRV: Necessary but not sufficient?

Hi, all.

Maybe this is something that someone has already posted, but just looking at the prevalence numbers in PWCs and in the general population, it looks to me as though we could conclude that in order to develop ME/CFS, it is necessary to have the XMRV virus on board, but having this virus on board is not sufficient to cause one to develop ME/CFS.

I think that would explain why the prevalence among PWCs is nearly 100%, but at the same time there is a significant number of people in the general population who test positive for XMRV, but are not ill.

It has been mentioned that perhaps the immune system must be weakened in order for a person to succumb to the virus and develop ME/CFS. That's what it looks like to me, too.

For what it's worth, I think this meshes well with the GD-MCB hypothesis, but I won't drone on about that here. If anyone is curious, the papers on it are posted on Cort's site.

Best regards,

Sofa, UK
Necessary but not sufficient: absolutely, that's a succinct expression of what we can conclude.

One of my favourite guesses as to why XMRV causes CFS/ME in some people and not in others is that the detailed symptomology depends on which specific cells the XMRV happens to infect. Thus it might just give the 3.4% healthy guys an allergy to something like celery which they don't eat anyway...or it might give you autism, or it might give you prostate cancer, or it might give you CFS/ME...

The other theory I like is that the XMRV can only get really busy when there's some other factor to help it grow out of control, most typically extreme stress or severe infection, just because that fits our experience quite well and even brings the 'psychological' factors into play. Maybe the 3.4% healthy people just never had that big a level of stress/cortisol yet.

Holmsey, your earlier points about Pall, Gupta etc were excellent. The XMRV research doesn't throw all those other people's work out of the window at all, it just casts it in a new light and many of them will now have crucial contributions to the way things unfold. I think of XMRV as being the first real piece of the puzzle we can put definitively in place, and ALL the other evidence can now be fitted in around that. That's why the speculation is so exciting because we've suddenly got a vast quantity of clues we can piece together. At the same time, we may also start to find out which of the alt-health practitioners have been taking our money for nothing...

And I'm delighted you guys made up anyway while I was writing my earlier post! Guess I should have just left you to get on with it!

With that in mind I'll log out right now and take that well-deserved rest; catch you later folks.