Chronic Fatigue Syndrome — Could a "Stealth Virus" Be Lurking?

By John F. Joseph, MD, FACP, FIDSA, FSHEA, Associate Chief of Staff for Education, Ralph H. Johnson Veterans Administration Medical Center; Professor of Medicine, Medical University of South Carolina, Charleston, is Associate Editor for Infectious Disease Alert.

"It has been known for years that patients with chronic fatigue syndrome (CFS) have a defect in a major antiviral pathway, the 2-5A/RNase L pathway. The RNaseL produces non-specific viral cleavage and, thus, protects us from many viral infections (innate immunity).

Defects in this pathway not only lead to susceptibility to viral infections but may also increase our susceptibility to tumor development. The RNaseL gene, called Human Prostate Cancer 1 (HPC1), has a variant R462Q related to a potential etiologic agent of prostate cancer, a novel human retrovirus, xenotropic murine leukemia virus (MuLV), named XMRV.

So, it was by a bit of serendipity that a group of workers headed by several from the Whittemore Peterson Institute in Reno, Nevada, asked if XMRV could be associated with CFS. What led to any rationale connection between prostate cancer and CFS is not clear, but the question led to a series of experiments that culminated in a very recent publication showing an association between the presence of this retrovirus in the peripheral blood mononuclear cells (PBMCs) of patients with CFS.

We are dealing here with intricate science that surely ...