Rare Diseases in the U.S.

How are rare diseases defined?

  • A rare disease is any disease or condition which affects or directly impacts less than 200,000 people in the U.S.

How many people may have this disease?

This section is currently in development.

How rare are rare diseases?

Rare diseases may be rare individually, but together affect more than 30 million people in the U.S. Patients and families impacted by different rare diseases face many of the same challenges. Working together, rare disease communities can improve the lives of all patients living with a rare disease.

Rare Disease Day at NIH

At the end of February each year, NCATS and the NIH Clinical Center sponsor Rare Disease Day at NIH as part of a global observance. Rare Disease Day at NIH aims to raise awareness about rare diseases, the people living with them, the NIH research collaborations that are underway to address scientific challenges and to advance new treatments.

Living with a Rare Disease

Individuals who live with a rare disease can face challenges that can be overwhelming. It is normal for patients, their families, and caregivers to experience a variety of stresses that may change over time.

These challenges may include: 
  • Limited information about the disease and treatment
  • Financial and economic difficulties
  • Adjustments to daily activities and roles
  • Social consequences and isolation
  • A wide range of feelings and emotions
  • Caregiving responsibilities
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Improving Quality of Life
The medical team may not be aware of the multiple ways that a rare disease can change the quality of life of the patient and family. Children and adults who have a rare disease and their caregivers are encouraged to talk about their needs with the medical team and to reach out for the support they require.

There are many ways to receive support:
  • The medical team can develop a care plan and can make referrals
  • Family, friends, and religious leaders can provide support
  • Patient and caregiver organizations can help connect to others
  • Rare disease organizations have informational resources
  • Organizations can provide disability and financial support
  • Crisis support helplines can offer immediate assistance by phone
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Many diseases impact the quality of life and financial stability of patients and families. The following organizations can offer assistance directly or can help find other resources. The organizations and resources are listed for information purposes only. Inclusion on this list does not reflect an endorsement by GARD or the NIH.

Last Updated: Nov. 8, 2021