This is from earlier in the year (Feb 2013) but I don't remember seeing it, and I can't find it on the forum. The results are negative. Human Endogenous Retrovirus-K18 Superantigen Expression and Human Herpesvirus-6 and Human Herpesvirus-7 Viral Loads in Chronic Fatigue Patients Brendan Oakes, Matthias Hoagland-Henefield, Anthony L. Komaroff, Jessica L. Erickson, and Brigitte T. Huber Clin Infect Dis. (2013) 56 (10): 1394-1400. doi: 10.1093/cid/cit086 First published online: February 13, 2013 http://cid.oxfordjournals.org/content/56/10/1394.short Results. HERV-K18 env transcripts were not significantly different between healthy control subjects and CFS patients. Also, HERV-K18 env transcripts did not correlate with HHV-6 viral copy number or HHV-7 viral copy number in either PBMCs or saliva. HHV-6 viral copy number and HHV-7 viral copy number in both PBMCs and saliva were not significantly different between healthy control subjects and CFS patients. HERV-K18 env transcripts, HHV-6 viral copy number, and HHV-7 viral copy number did not correlate with CFS symptom severity. Conclusions. We fail to demonstrate a difference in HERV-K18 env transcripts, HHV-6 viral copy number, and HHV-7 viral copy number between CFS patients and healthy controls. Our data do not support the hypothesis of reactivation of HHV-6 or HHV-7 in CFS.