Right now, there are more than 2.3 million people in the world who are affected by Multiple Sclerosis (MS). 
However, because the Centers for Disease Control does not require physicians in the United States to report new cases of MS and because symptoms of the disease can be invisible, only those cases in the United States can be estimated.
What is Multiple Sclerosis?
Multiple Sclerosis is an unpredictable and chronic disease that attacks the central nervous system, which consists of the optic nerves, brain and spinal cord. MS is believed to be an immune-mediated disorder, in which the immune system goes haywire and attacks healthy nerve tissues in the central nervous system.
Who can develop Multiple Sclerosis?
Anybody can develop MS, but the disease strikes more women than men.  According to the Mayo Clinic, the following risk factors are associated with Multiple Sclerosis:
- Age: Multiple Sclerosis can happen to someone at any age; however, it most commonly strikes people between the ages of 15 and 60 years of old.
- Climate: Multiple Sclerosis is more common in temperate countries such as the northern United States, southern Canada, Europe, southeastern Australia and New Zealand. 
- Race: Caucasians particularly those of Northern European descent, are at an increased risk of developing Multiple Sclerosis. People of African, Native American and Asian descent are at the lowest risk.
- Certain autoimmune diseases: If you have thyroid disease, diabetes type 1 or inflammatory bowel disease, you are at a slightly higher than average risk of developing MS.
- Family genetics: If one of your parents or siblings has or had MS, it makes the likelihood you will develop it much higher than average.
- Gender: Women are two times more likely to develop Multiple Sclerosis than men.
Top 9 Signs and symptoms of Multiple Sclerosis
1. Vision problems
One of the most common signs of Multiple Sclerosis is vision problems, which are clinically referred to as “optic neuritis.”
Vision problems associated with MS can cause an inflammation of the optic nerve and disrupt a person’s central vision. It is common to have blurred vision in one or both eyes, double vision, and a loss of vivid colors or clarity.
It may be difficult to notice vision disturbances immediately because it can happen slowly. A person may also experience pain from the vision loss when looking from side to side.
2. Pain and muscle spasms
Another common sign of MS is chronic pain and muscle spasms. According to a study performed by the National Multiple Sclerosis Society, almost half of all MS patients had either chronic pain or significant clinical pain. 
Stiffness or spasms in muscles is also very common and it can involve feelings of twitching, painful and uncontrollable jerking. The legs are commonly affected by MS, but the pain can also occur in the back.