Skip to navigation Skip to content

Understanding MS



In this article

Overview of MS

MS is a chronic, often disabling disease that affects the central nervous system (CNS), which is comprised of the brain, spinal cord, and optic nerves. Within the CNS, the immune system attacks myelin — the fatty substance that surrounds and insulates the nerve fibers — as well as the nerve fibers themselves. When myelin is damaged or destroyed, the ability of nerves to conduct electrical impulses to and from the brain is disrupted, producing the various symptoms of MS. Learn more about what MS is and its impact on the CNS.

What Is MS

Courses /Types of MS

There are 4 disease courses, each of which might active or not active, and with or without progression.

Cause and epidemiology

The exact cause of MS is unknown. Most researchers believe that the damage to myelin is immune-mediated, that is, it results from an abnormal response by the body’s immune system. Normally, the immune system defends the body by attacking foreign invaders such as viruses or bacteria. But in an immune-mediated response, the body attacks its own tissue.  In MS, the body attacks myelin. Scientists do not yet know what triggers the immune system to do this.  Most agree that several factors are involved, including genetics, gender, and environmental factors. Learn more about the potential causes of MS.
Approximately 2.3 million people worldwide have MS. Worldwide, MS occurs with much greater frequency in areas farther from the equator.  However, prevalence rates may differ significantly even within a geographic area, where latitude and climate are fairly consistent.  These differences demonstrate that geographical factors are not the only ones involved. Learn more about who gets MS

Diagnosis and treatment

At this time, no single test is available to identify or rule out MS. Several tests and procedures are needed to determine if a person meets the criteria for a diagnosis of MS.  Learn more about the diagnostic criteria and what tools are used to make the diagnosis
Although there is still no cure for MS, effective strategies are available to:

Healthcare team

A complex disease requires a comprehensive approach. For most people with MS, the neurologist functions as the leader of the team; a comprehensive MS care team includes additional healthcare professionals:
  • nurse
  • rehabilitation
  • mental health
  • nutrition
  • urology
  • primary care
  • wellness

Next module


© 2020 The National Multiple Sclerosis Society is a tax exempt 501(c)3 nonprofit organization. Its Identification Number (EIN) is 13-5661935.