Multiple sclerosis: etiology and epidemiology.

Multiple sclerosis (MS) is a demyelinating, auto-immune disease which affect the central nervous system. The research seems to implicate a small or incomplete slow-growing virus as the causative agent. The measles virus has been suspected because of high titers of measles antibodies in MS patients' serum and cerebrospinal fluid. An immunological deficiency in MS patients may be linked to genetic factors such as HL-A tissue types and histocompatibility antigens. Genetics and socioeconomic conditions may also result in the distinct geographical pattern of MS distribution in the world.