What Is Rare Diseases?

A rare disease is one that affects fewer than 200,000 people in the United States. There are nearly 7,000, affecting more than 25 million Americans.

*Health information sourced from the Centers for Disease Control and Prevention (CDC) and MedlinePlus, a service of the U.S. National Library of Medicine. co-pay.com is not affiliated with or endorsed by the U.S. government.

A rare disease is one that affects fewer than 200,000 people in the United States. There are nearly 7,000 rare diseases. More than 25 million Americans have one.

Rare diseases:

  • May involve chronic illness, disability, and often premature death
  • Often have no treatment or not very effective treatment
  • Are frequently not diagnosed correctly
  • Are often very complex
  • Are often caused by changes in genes

It can be hard to find a specialist who knows how to treat your rare disease. Disease advocacy groups, rare disease organizations, and genetics clinics may help you to find one.

NIH: National Institutes of Health

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