The strongest risk factor for multiple sclerosis known so far is infection with the Epstein-Barr virus (EBV). An EBV infection has been shown to increase the risk of developing the autoimmune disorder by 32 times. However, this infection alone is not enough to trigger the disease. Multiple interconnecting factors, including genetics, lifestyle, demographics, and environmental factors, all are thought to play a role in MS development.
Multiple sclerosis is an autoimmune disorder caused by a person’s immune system accidentally attacking that individual’s own healthy tissue. The disorder is not transmissible; it cannot be passed from one person to another.
Multiple sclerosis is more common in women than men, and the disease is mostly diagnosed in adulthood. White people are more often affected than Asians or Latin Americans, while rates of MS are higher among Black people than white people. MS is most common in temperate regions of the world that are further from the equator. People with certain genetic mutations or autoimmune diseases, as well as those who smoke or are obese, are also more likely to develop the condition.
No. The immune attack that drives multiple sclerosis is believed to broadly result from an immune system malfunction as immune cells fight off potential infections that are encountered throughout life. There have been reports of toddlers developing MS symptoms before age 2, but most children who develop the condition do so in their early teens.
The criteria used to diagnose multiple sclerosis require the presence of brain or spinal cord lesions on MRI scans that appear over time. Even if a person is found to have MS-like lesions at one point in time, there needs to be definitive evidence that lesions are developing over time for a formal diagnosis of MS to be made. Thus, by definition, it is not possible for MS to suddenly develop.