Rare Disease Day takes place on 28 February every year.1 Its aim is to raise awareness of rare diseases, and most importantly, the impact they have on the daily lives of patients and their families.1 While many of us will know this date as Shrove Tuesday (and may look forward to one too many pancakes), hundreds of patient organizations across the world will be holding events to advocate rare diseases.1

A rare disease, also called an orphan disease, is defined differently in Europe and the USA:1

  •  USA: affects fewer than 200,000 Americans at any given time2
  • Europe: affects fewer than 5 in 10,000 people3

While some rare diseases will affect less than a hundred people, it is estimated that in total, 25 million Americans and 30 million Europeans are living with a rare disease.2,3

There are approximately 5,000–8,000 rare diseases.3 The majority of these are caused by changes in genes called genetic mutations. However, some can be caused by environmental or toxic conditions.2 There are a wide variety of symptoms and disorders which can present in patients, even in those with the same disease.1 For example, the Jumping Frenchmen of Maine is the name of an unusual disorder characterized by an extreme startle to unexpected noises or sights.2,4 The exact causes of this disorder are unknown.4

Over half of rare diseases affect children.1 Many of the diseases are well-known by the general population, such as cystic fibrosis, while some most people will not have heard of, such as spinal muscular atrophy and lysosomal storage disorders.3

A key challenge for patients with rare diseases is receiving a timely and correct diagnosis.1,2 It is estimated that for a third of patients, it can take 1–5 years to receive an accurate diagnosis.2 A problem with diagnosing rare diseases is that they are often difficult to diagnose in the early stages, with symptoms being absent, or being confused for other diseases.2 For example, the genetic disorder adrenomyeloneuropathy, characterized by progressive problems with the brain, spinal cord and peripheral nerves is often misdiagnosed as multiple sclerosis.2

Currently, there are no effective cures for most rare diseases, and this is accompanied by a lack of scientific research.1,3 However, the number of scientific publications about rare diseases is increasing, with an average of five new diseases described in the scientific literature each week.3

Initiatives such as Rare Disease Day aim to raise awareness of these unusual disorders. Each year has a theme, for example, this year there is a focus on research: “Rare Disease Day 2017 is an opportunity to call upon researchers, universities, students, companies, policy makers and clinicians to do more research and to make them aware of the importance of research for the rare disease community.”1

Want to find out more? Visit the Rare Disease Day website at: www.rarediseaseday.org.    

References: 1. Rare Disease Day Website. Available at: http://www.rarediseaseday.org/article/what-is-a-rare-disease. Last accessed: February 2017. 2. US FDA. Orphan products: hope for people with rare diseases. Available at: https://www.fda.gov/Drugs/ResourcesForYou/Consumers/ucm143563.htm. Last accessed: February 2017. 3. EMA. Orphan designation. Available at: http://www.ema.europa.eu/ema/index.jsp?curl=pages/regulation/general/general_content_000029.jsp Last accessed: February 2017. 4. NIH. Jumping Frenchman of Maine. Available at: https://rarediseases.info.nih.gov/diseases/6803/jumping-frenchmen-of-maine. Last accessed: February 2017.