8Prevalence
Multiple sclerosis is a more common health issue than neuromyelitis optica. It is estimated that around 1 million people have this condition in the United States. As for neuromyelitis optica, there are approximately 250,000 cases in the world, with around 15 percent of the cases occurring in the United States. While people with multiple sclerosis tend to live in regions farther from the equator, neuromyelitis could be found in most climates. Also, both conditions tend to be less common in men than in women. [8]
