I've been reading a lot online lately (mainly about XMRV), but in almost all articles about CFIDS, pain seems to be a pretty big factor. I'm your typical post-viral case (10 years, housebound, if I bike/walk for over 15 minutes I crash for days after) and as far as I know pain is just one of the possible criteria someone can match, but it's not a requirement. On patientslikeme.com everyone of the "300 something patients like me" seems to have CFIDS as well as fibro, so, er.. that's not like me! Surely I can't be the only one with only CFIDS? (my only pain problem is the occasional migraine-from-hell in the back center of my head, most likely to occur when I do more than I should) Also: I couldn't really find anything on this on pubmed etc, but what could be the difference between having only CFIDS and having both??