:::If we merge there should be some discussion about nomenclatures. this recent review does not indicate that PVFS and Chronic fatigue syndrome are the same. It says, Chronic fatigue syndrome (CFS) is a specific clinical condition" and "Similar disorders have been described for at least two centuries and have been differently named neurasthenia, post-viral fatigue, myalgic encephalomyelitis and chronic mononucleosis." This review also seems to draw some distinctions between the two. 

 :::The Alternative names for chronic fatigue syndrome article says, "Several of the more common alternative names used to describe what most believe to be the same condition or subtypes include post-viral fatigue syndrome, benign myalgic encephalomyelitis (often shortened to myalgic encephalomyelitis, ME), and chronic fatigue immune dysfunction syndrome (CFIDS)." But there is no source for that assertion and reading the article I didn't find sources stating the nomenclatures are the same illnesses or subtypes.