As far as i'm aware Borrelia is an exclusionary criteria from ME anyway although I guess that depends upon which diagnostic criteria the physician is using. This extensive search is certainly worthwhile but I think it's unwise to pin hopes on this given the history pathogens have had in terms of ME research. From a personal standpoint I doubt any infectious agent lies at the heart - perhaps they simply serve to exacerbate the problem in those who have them. I agree that even if these pathogens are hiding away in tissues there should be some evidence of the active infection. As far as i'm concerned if the pathogen is inert in these tissues there should be no symptoms so I feel that line of thought should be throw out instantly.