PwMS rarely have antibodies against EBV that are produced within the brain and spinal cord. Some antibodies are produced but are part of the general immune response that occurs in MS. Only rarely are anti-EBV antibodies detectable in the spinal fluid in patients with CIS, the earliest stage of MS. These data argue against a direct infection of the brain and spinal cord with EBV in PwMS.
Otto et al. Neurology. 2011 Apr 12;76(15):1316-21.
"May be EBV affects the immune system in MS in the periphery? Or by preventing the immune system producing antibodies against itself within the brain and spinal cord? The evidence that EBV is involved in MS is too compelling. We simply need to find out how it is involved in the disease; this is very important research."