The world’s rarest disease has only two victims.

Only two people in history have been diagnosed with Fields’ disease. The disease’s name comes from the only two patients, Catherine and Kirstie Fields, a pair of twins. The condition is a neuromuscular disease that forces the twins to use wheelchairs and makes them unable to write. They have had the disease since the age of 4, and their condition has degenerated over time. Because this disease has never happened to anyone before, doctors can’t tell them what they can expect from the disease in the future.
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