It is a disease of the central nervous system.The symptoms of this disease is myelin (fatty insulating sheathes protecting nerve fibres) becomes damaged and scarred. It affects a person's motor, sensory and even cognitive functions. The causes of Multiple sclerosis are genetic and environmental factors. The impact and symptoms of Multiple sclerosis depends on a person's ability to participate in everyday activities different from person to person.
Prevalence in 2007 was significantly greater in Donegal (northwest) (290.3/105, 95% CI 262.3 to 321.7) compared with 2001 (184.6/105; 162 to 209.5). In Wexford (southeast), there was a non-significant increase in prevalence in 2007 compared with 2001. Prevalence was significantly higher in Donegal than in Wexford (144.8/105; 126.7 to 167.8, p<0.0001) and South Dublin (127.8/105; 111.3 to 148.2, p<0.0001).