Strange but True. Maybe that's the impression that comes to your mind after hearing about a rare disease. Besides having unique symptoms, rare diseases are sometimes fatal and cannot be treated. Come on, recognize some of the rare diseases in the world with the following unique symptoms! Rare diseases are diseases that rarely occur or have a very small number of sufferers. A study states that there are at least more than 7,000 rare diseases suffered by 8-10 percent of the world's population. This means, there are about 500 million people in this world who suffer from this rare disease. Several Types of Rare Diseases that Hear Foreign Of the many rare diseases in the world, here are some of them: 1. Progeria Progeria is one of the rare diseases that can occur in children. This disease makes the child's body age rapidly. That is due to abnormal genetic changes in the child's body. But unfortunately, it is not yet known exactly what triggers these genetic changes. ...