The rare diseases is that they are not known by health professionals as they are not taught to them. Rare diseases are often perceived as not being a public health problem by health authorities because they are rare and are not the object of research programs because of the lack of data and they do not attract interest from the pharmaceutical industry because the potential market is too limited, thus limiting the funding of the research into this area.
Rare diseases are often life-threatening or chronically debilitating diseases. They are mostly inherited and therefore affect only very few people rendering them hard to diagnose and propose the best therapy. In EU countries, any disease affecting fewer than 5 people in 10 000 is considered rare. The number may seem small, but collectively it translates into approximately 246 000 people throughout the EU's 27 member countries. Most patients suffer from even rarer diseases affecting 1 person in 100 000 or more.
It is estimated that today in the EU, 5-8000 distinct rare diseases affect 6-8% of the population – between 27 and 36 million people presenting a considerable problem for the social insurence and health program.
The specificities of rare diseases – limited number of patients and scarcity of expertise – are conditions that enforce international collaborations and networking to ensure that scarce knowledge is shared and resources combined as efficiently as possible, in order to tackle rare diseases as effectively as a whole.
The EU has recognized the problem and has started an initiative on Rare and Orphan diseases to support research and strong EU-wide networking to generate a common platform for better diagnostic approaches, training of future medical professionals and facilitating exchange of expertise.