“In July, the Journal of Infectious Disease reported a genomic study of postinfective fatigue in patients with previous Epstein-Barr virus (EBV) infection (also known as infectious mononucleosis). Researchers, led by Andrew Lloyd and collaborators in Australia and the U.S., compared seven subjects whose illness did not resolve after six months with eight matched subjects who promptly recovered from the original infection. The seven who were still ill at six monthswith whats termed postinfective fatigue syndrome or PIFSall met the 1994 international case definition for CFS, making this study highly relevant to the CFS community.
Analysis of samples collected over time ultimately revealed 35 genes for which changes in expression were consistent with the course of the illness in the seven subjects with postinfective fatigue. These genes included several that are involved in signal transduction pathways, metal ion binding and ion channel activity.
According to the researchers, Gene expression correlates of the cardinal symptoms of PIFS after [EBV] have been identified. Further studies of these gene products may help to elucidate the pathogenesis of PIFS. Since the studys PIFS subjects also met the case definition for CFS, the implications for the postinfective subset of CFS are similarly hopeful.
This report builds on an earlier study of PIFS and postinfectious CFS reported in the September 16, 2006 British Medical Journal. This study tracked 253 individuals with EBV, Ross River virus and Q fever infection and found that roughly 12% of all the study subjects went on to have PIFS and CFS regardless of the specific agent causing the original infection. This supports the concept that there are viral triggers for CFS in at least a subset of patients.”