22 Hard-To-Detect Illnesses, From The Commonplace To The Truly Bizarre

22. Congenital Insensitivity To Pain

Sufferers from this rare disease, also known as congenital analgesia, are unable to feel physical pain. While this disease may sound like it is capable of turning people into superheroes, it can actually cause a lot of problems, as suffers may do things like burn themselves without realizing it, or fail to treat other ailments whose primary warning signs are pain.