The Wall Street Journal had a recent article about the clash between patients and scientists over the cause of chronic fatigue syndrome. Evidently, some patients with CFS accuse the CDC of deliberately obstructing or delaying the publication of data showing a link between CFS and viruses such as XMRV. I personally doubt the CDC or anyone else has deliberately suppressed any information. If anything, it is the CFS patients who seem one-sided in their advocacy of a link between XMRV and CFS, given that some studies have failed to show a connection. As I indicated in a previous post, there is some evidence of a connection between CFS and chronic infections of several kinds, but the data is still spotty and I don't think anyone knows for sure what is causing cases of CFS. In addition, focusing too much on particular viruses like XMRV may direct attention away from the possible role played by other viruses, such as EBV, CMV, HHV-6, and enteroviruses, much less other pathogens such as bacteria and parasites.
Regarding the bacterial and parasitic infections, it is even possible that some CFS cases are due to infections caused by tick bites. Another recent article on msnbc's website discusses the increase in hard-to-diagnose (and often hard-to-treat) tick-born infections, and some of these have symptoms similar to CFS (including severe fatigue and "brain fog"). Since CFS is a syndrome, and not a disease with a specific etiology, it's not yet possible to say how many different types of infections or other conditions are behind CFS cases. When patients cling to one theory of CFS and attack scientists researching the syndrome, one fears that this will only hinder the pace of research. On the other hand, I haven't seen many scientists discuss the possibility of multiple infectious agents behind CFS cases, and this may represent a bias on their part which is also holding back the research. Too many people, patients and scientists included, seem to be looking for a single cause of the syndrome. I wish more studies were structured to test CFS patients for multiple pathogens using the best assays currently available.