Given the great diversity in CFS symptoms, disclosure of the medical histories and clinical conditions of the high number of WPI's XMRV-infected CFS patients is critical. "Of course, this would generate more questions, but a cleaner association is needed," Vernon says. "I don't know why WPI won't provide this."
So far, Mikovits has refused to budge. "No additional medical histories or anything about the patient population would shed any light on XMRV," she says.
Sleuthing on her own, Vernon was able to uncover some suggestive information about the 32 CFS patient samples about which WPI originally reported assay results. Only 12 tested positive on more than one assay (WPI ran four assays); of those 12, four had been diagnosed with cancer. Another 13 of the total 67 XMRV-positive CFS samples also had cancer.
"Validation and confirmation are not coming as fast as one might like, that's for sure," says John Coffin. "If you can't establish a disease association, then there is less interest in developing a drug, obviously." Coffin also notes that uncertainty remains about whether or not the virus is replicating. "If it does so, like HIV, then an antiretroviral would be very effective. But if not, as it appears in prostate cancer, a drug would not make any difference."