Rare disease in boy

A disease may be considered rare in one part of the world, or in a particular group of people, but still be common in another.Global Genes have estimated that more than 300 million people worldwide are living with one of the 7,000 diseases they define as "rare" in the United States.There is no single, widely accepted definition for rare diseases. Some definitions rely solely on the number of people living with a disease, and other definitions include other factors, such as the existence of adequate treatments or the severity of the disease.In the United States, the Rare Diseases Act of 2002 defines rare disease strictly according to prevalence, specifically "any disease or condition that affects fewer than 200,000 people in the United States,"[3] or about 1 in 1,500 people.