An old problem
I ran across this article a couple of days ago. The very short summary is that there is new but as of yet unconfirmed evidence that a certain virus causes what has come to be known as chronic fatigue syndrome.
This topic is of particular interest to me because I had it, and I can't say that it ever really went away.
In August of 2001 I was sick with a fever over a weekend immediately following a hard training session, and my post-sickness fatigue didn't go away for a few years. No amount of sleep, change in diet, rest, doctors' visits, or research could provide a cure for my tiredness. One thing I did know was that the antibodies related to the Epstein-Barr virus showed the pattern particular to people who were recovering from mononucleosis. Other than that, I knew nothing.
But, in May 2005 I found myself suddenly feeling better, and since then I've lived in a delicate balance between near-normalcy and recurrence of symptoms if I overstress myself by running too much, not sleeping enough, or doing other generally unhealthy things.
Of course I resent my condition for basically ruining the second half of my college running career, but dealing with it has also changed my perspective, in some cases for the better. I can name a few things that I would never have done had I not been prevented from running, and had I not been extremely tired for months on end. It wasn't all bad, but I still would rather be without it. That's why it's exciting for me to hear about possible progress in the research, and the founding of an institute for related research.