Epstein-Barr virus and multiple sclerosis.

Epstein-Barr virus (EBV) is a human DNA herpesvirus infecting more than 90% of the world's population. EBV is the etiological agent of infectious mononucleosis (Pfeiffer's disease). Furthermore, diverse malignancies such as Burkitt and Hodgkin lymphoma have been associated with EBV. More recently, a possible role for EBV has been suggested in chronic inflammatory/autoimmune diseases like rheumatoid arthritis and systemic lupus erythematosus as well as in multiple sclerosis (MS). MS is currently regarded as a disease with multifactorial etiology, EBV being one possible factor in MS manifestation: Infectious mononucleosis has been shown to increase the risk of developing MS later in life. EBV seroprevalence rates are higher in MS as compared to controls, in adult as well as in pediatric MS patients. Moreover, EBV antibody titres and EBV specific T-cells are increased in MS patients as compared to healthy individuals. Recently, CNS B-cells of MS patients have been reported to harbour EBV. However, there is still controversy whether EBV could be a causative agent as opposed to an innocent bystander in the pathogenesis of MS. This review summarizes current knowledge on the association of EBV and MS including a critical discussion of equivocal findings.