The Puzzle of Chronic Fatigue - For 20 years, a doctor in upstate New York has been trying to prove that an outbreak of the strange syndrome in his community was caused by a virus. Now new evidence is reopening the case


The Puzzle of Chronic Fatigue
http://online.wsj.com/article/SB10001424052748704005404576176823580854478.html
Wikipedia: Retrovirus
http://en.wikipedia.org/wiki/Retrovirus