Human herpesvirus 6 and multiple sclerosis: potential mechanisms for virus-induced disease.

Multiple sclerosis (MS) is a debilitating neurological disease of unknown cause that affects people between 20 and 40 years of age. While several viruses have been associated with MS, none has proven causative. Human herpesvirus 6 (HHV-6) is one agent that may play a role in MS. Some studies have demonstrated an association between HHV-6 and MS based on immunological and molecular data, suggesting that a subset of MS patients may have reactivation of this widespread herpesvirus. New studies investigating the biology of HHV-6 have given insights towards understanding how HHV-6 may play a role in MS pathology. By inducing molecular mimicry or excessive complement activation, HHV-6 reactivation may have the potential to trigger autoimmunity and tissue damage associated with MS lesion development.