According to Dharam Ablashi, DVM, MS, "HHV-6 infection usually occurs in childhood during the first year of life and then the virus becomes latent." HHV-6 has two forms designated as HHV-6A and HHV-6B. It is HHV-6B that is associated with roseola and over 90% of adults retain this virus dormant in their system throughout their lives. Ablashi states that "variant A is more common in AIDS patients and patients with CFS."
As the research developed with HHV-6, many researchers, including Dr. Ablashi, performed studies to determine whether that virus might be the cause of CFS. These studies, while not always consistent, have often found a majority of CFS patients show signs of recurrent HHV-6 infections. This is not so with healthy persons.
(Source: www.ImmuneSupport.com. Read complete article at http://www.immunesupport.com/library/showarticle.cfm/id/4556)