This means that Hairy cell leukemia, or a subtype of Hairy cell leukemia, affects less than 200,000 people in the US population. Ophanet, a consortium of European partners, currently defines a condition rare when it affects 1 person per 2,000. They list Hairy cell leukemia as a rare disease.
In fact, some of the oldest alphabetic symbols have been found in Central America (2,500 years ago), China (more than 3,000 years ago), and the Middle East (more than 5,000 years ago). One of the earliest forms of the alphabet was hieroglyphics. Hieroglyphics were single symbols that stood for entire words.
The first iteration of a spelling alphabet was created by the International Civil Aviation Organization in the mid-1920s to facilitate safe and efficient air traffic communication, evolved until the mid-1950s and has been the spelling standard for virtually all national and international organisations since the 1960s.