Rare Disease Day USA | Last Day in February

Each year on the last day in February, Rare Disease Day brings awareness and education about rare diseases and the suffering they cause. 


A rare disease is defined differently in different parts of the world. In Europe, a rare disease is one that affects fewer than one in 2,000 people, and in the United States, the standard is 1 in 200,000. Driving home how infrequent some of these conditions are, the observance sometimes occurs on the rarest date of the year – February 29th. Even so, the day is more predictable than many rare diseases. They can be difficult to diagnose and even more difficult to understand. While a majority of the conditions are genetic in origin, still others are the result of infections, environmental or degenerative factors.

Often people with rare diseases face a multi-faceted uphill battle; with few sufferers, there are fewer voices to bring awareness to their needs for research, medical, and financial support. As a result, their physical, social, and oftentimes mental burdens add up.

Rare Disease Day brings those voices together to help lift some of those burdens and bring awareness to light.


  • Help raise awareness among the general public and decision-makers about rare diseases and their impact on patients’ lives.
  • Learn more about a rare disease impacting someone you love.
  • Find out how you can make a difference in their life.
  • Donate to a rare disease organization to support research into cures and treatments.
  • Use #RareDiseaseDayUSA to post on social media.


First observed in Europe in 2008, Rare Disease Day was established by Eurordis, (the European Rare Disease Organization). In 2009, NORD was asked by EURORDIS  to sponsor Rare Disease Day in the United States. NORD accepted and 2014 celebrates the 6th annual RARE DISEASE DAY USA.

Rare Disease FAQ

Q. How many people are impacted by rare diseases?
A. It may seem like rare diseases have a lesser impact on the human population, but when you consider how many rare diseases there are, the impact adds up. By the numbers, 1 in 10 Americans is impacted by a rare disease.

Q. Why are rare diseases difficult to diagnose?
A. There are several factors:

  • Symptoms may be similar to another condition.
  • There are no available tests to diagnose the disease.
  • The treating physician or medical team may not be familiar with the condition.