A disease or disorder is defined as rare in Europe when it affects fewer than 1 in 2000.

A disease or disorder is defined as rare in the USA when it affects fewer than 200,000 Americans at any given time.

One rare disease may affect only a handful of patients in the EU (European Union), and another may touch as many as 245,000. In the EU, as many as 30 million people may be affected by one of the estimated 6000-8,000 existing rare diseases.

80% of rare diseases have identified genetic origins whilst others are the result of infections (bacterial or viral), allergies and environmental causes, or are degenerative and proliferative. 50% of rare diseases affect children.

A rare disease also referred to as an orphan disease, is any disease that affects a small percentage of the population.

Most rare diseases are genetic, and are present throughout a person’s entire life, even if symptoms do not immediately appear. In Europe, a disease or disorder is defined as rare when it affects less than 1 in 2000 citizens.

Rare diseases are characterised by a wide diversity of symptoms and signs that vary not only from disease to disease but also from patient to patient suffering from the same disease.

Relatively common symptoms can hide underlying rare diseases, leading to misdiagnosis.

While an individual disease might be labeled as “rare”, the total number of persons in Europe suffering from one of the over 6000 different identified rare diseases is estimated at over 30 million.

Rare diseases not only affect the person diagnosed – they also impact families, friends, care takers and society as a whole.

An individual rare disease may affect only one person in a million, but all together, rare disease patients comprise 6% to 8% of the EU population.