Two years ago, some researchers announced they'd found traces of a mouse-related virus named XMRV in the blood of a number of chronic fatigue patients. The headline-making discovery fueled hope that perhaps the mysterious illness' cause had finally been found. The virus also was found in certain prostate tumors.
Tuesday, the journal Science declared that link "seriously in question." It published two new studies that say the earlier findings almost certainly were the result of laboratory contamination. If so, that would explain why at least 10 other studies have failed to find any connection between the purported infection and human illness.