Two studies published this January by separate research teams have conclusively identified Epstein-Barr virus infection as the cause of multiple sclerosis, and the mechanism by which the immune response to EBV infection triggers an attack on the myelin sheath, the insulation that enables high-speed neuronal transmission.

Antibodies to the EBNA1 protein of Epstein-Barr virus can cross-react with glial cell adhesion molecule (GlialCAM), a component of the myelin sheath. The findings are the first to report a mechanism for how viral infections can cause autoimmune disorders.