What causes multiple sclerosis? Getting closer to the answers

MS risk is becoming less of a mystery as we gain a better understanding of its causes

Multiple sclerosis (MS) is a complex neuroinflammatory/neurodegenerative disease of the central nervous system. Recent work1,2 has significantly advanced our understanding of the aetiology of MS, emphasising the importance of infection with Epstein–Barr virus as a significant driver of MS risk. MS manifests clinically as neurological dysfunction affecting any area of the central nervous system, in particular the optic nerves, spinal cord, and brainstem. Most people with MS (90%) present with relapse onset MS where episodes of neurological dysfunction are followed by partial or full recovery but over time, disability almost invariably accumulates (secondary progressive MS).3 In contrast, 10% of people present with progression from disease onset, termed progressive onset MS.3 In the developed world, MS is one of the leading causes of neurological disability in young adults, and as the median age of onset in Australia is between 35 and 40 years,4 it affects people in their most productive years. Consequently, the economic and social costs to individuals and the wider community are high. In 2017, we estimated the cost of MS to Australia was $1.7 billion annually and increasing significantly each year.5 Currently, there is no cure for MS, but significant gains have been made in its treatment, particularly the use of highly effective disease‐modifying therapies and the development of comprehensive care through specialised MS clinics. However, no current treatment can stop or reverse the neurodegenerative component of the disease.3