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.
Sumer, an ancient civilization of southern Mesopotamia, is believed to be the place where written language was first invented around 3200 BC. Limestone Kish tablet from Sumer with pictographic writing; may be the earliest known writing, 3500 BC.