| With KUOW Public Radio
The mystery of why the Pacific Northwest has one of the highest rates of multiple sclerosis in the world is as enduring as the mystery of the D.B. Cooper hijacking. And has proven about as difficult to crack.Recently, however, scientists have been closing in on some likely triggers that may be causing the body to hijack its own immune system and turn on itself. Those new findings could lead to new treatment strategies in the future.MS is a sneaky, unpredictable autoimmune disease that damages nerves and can impair vision and mobility as well as thinking and memory. The prevalence of MS here is about triple the level in the lower part of the United States, and many more times higher than elsewhere in the world. In King County, there are 9,000 known patients, and a growing number of them are children.The prevalence is so high here that the Northwest chapter of the National Multiple Sclerosis Society has posted giant billboards around the city for the past several years asking questions like these: Is it the trees? Is it the rain?The questions may have been rhetorical, but the billboards were a reminder of the need to keep digging for answers about what causes MS.On a macro scale, scientists actually do know why the rate appears elevated here.