On one of my previous posts, I mentioned that a protein called APOBEC3 strongly exhibits retroviral replication. A recent study by Robert Silverman of the Cleveland Clinic confirms this finding. Five macaque monkeys were infected with XMRV - they showed an initial viremia, subsequently the virus became very difficult to find in the blood, but when the monkeys were sacrificed, the virus could easily be found in the spleen, lungs, lymphoid tissues, and prostate.
Ironically, the same patterns in certain blood cells were noted that exists in a cohort of ME/CFS patients. Also, the virus shows an initial acute phase, followed by periods of reactivation. Unfortunately, none of the animals displayed any clinical symptoms. The plausible explanation is that the length of the study was insufficient, or their immune systems were not presented with a challenge, or there was a lack of a necessary herpesviral co-infection to cause disease.