The Role of Infectious Agents on Pathogenesis of Multiple Sclerosis

Multiple Sclerosis (MS) is a complex autoimmune demyelinating disease of the central nervous system. Although the main cause of MS is still unknown, several risk factors may contribute in MS development. In the search for the etiology of MS, infectious agents, genetic factors, and/or their combination were believed to participate in MS occurrence. The association between MS and infectious diseases was proposed by Pierre Marie in 1884. It was later accepted following epidemiological studies, analysis on twins, immigrants and animal model. This study aimed at investigating the possible relationship between infectious agents and MS. Our findings showed that viral agents such as EBV, borna virus, measles, mumps, and fungi are possible agents in MS development, while parasites may induce immunomodulatory effects. Identifying the relationship between MS and infectious agents and determining a special pathogenic agent for MS could lead to novel treatment strategies. Furthermore, it may result in developing preventive programs. Therefore, further studies are needed to understand and identify the infectious agents that might affect the pathogenesis of MS and their mechanism of actions.