While we’ve all heard of diseases, seen someone with a disease, and had a disease personally, it’s unlikely that we’ve encountered a rare disease. In the non-medical world, people use and interchange disease to mean infection, sickness, illness, or something similar. In the medical world, a disease is an abnormal condition that impairs bodily functions and is often associated with certain signs and symptoms.
Also called an orphan disease, rare diseases are those that are extremely uncommon and often have such low prevalence that a common doctor would not run into more than one case of that disease over a course of years, if ever. Here is a list of 10 diseases that rarely affect people.