Trying to find if there is any connection between microbes and MS two mechanisms have been proposed for discussion; the hygiene hypothesis and the prevalence hypothesis. The prevalence hypothesis has not received much support as much as the hygiene hypothesis; the hygiene hypothesis supports that exposure to certain infectious agents early in life is protective with the disease being a response to a late encounter with such agents. The prevalence hypothesis believes that the disease is due to an infectious agent more common in regions where MS is prevalent and where in most individuals it causes an ongoing infection without symptoms. After many years and only in a few cases it causes demyelination. Oligoclonal bands in the brain and cerebrospinal fluid in the higher percentage of patients, the association of several viruses with human demyelination encephalomyelitis, and finally the occurrence of demyelination in animals, include evidence for a virus as a triggering agent. Human herpes virus and Epstein-Barr virus are candidate viruses connected with MS. Individuals having never been infected by the Epstein-Barr virus are at a reduced risk of getting the disease whereas those infected as young adults are at a greater risk than …show more content…
Although in MS, the spinal cord signs are asymmetrical involving only a part of the long ascending and descending tracts, i.e., paraplegia and complete sensory loss are not usual. Clinical sings include: a rapidly evolving symmetrical or asymmetrical paraparesis or paraplegia occurring over several hours or days, ascending paresthesia, loss of deep sensibility in the feet, sphincter disturbance, and bilateral Babinski sign. An infectious illness is reported from some patients preceding the onset of the symptoms. In this case a postinfectious demyelinating disease is more likely to happen rather than