A disease might be rare by itself, but the number of people suffering from rare diseases are huge enough to be studied collectively since there are 7,000 rare diseases worldwide. In the U.S., about 25 to 30 million citizens suffer from rare diseases, for which the Orphan Drug Act provides incentives to companies to develop new drugs.

The perception of extreme rarity comes from the definition provided by the Act established in 1983, which states that a disease can be classified as rare if it affects fewer than 200,000 individuals in America. Extensive research has not been conducted in this area, hence medical expertise and treatments are not well developed.

There is a need to establish a body of documentation to frame public health policy regarding rare diseases. This is to help patients and families suffering with medical ambiguities. A consortium of 40 countries worked together to pool data on rare diseases

. Orphanet is currently the most comprehensive database on rare diseases worldwide.

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What The Study Found

In the first estimation of this magnitude, a recently published study in he European Journal of Human Genetics on September 16 found that 263-446 million or 3.5-5.9 percent of people are suffering from rare diseases globally at any given point. In Europe alone, 18 to 30 million people are patients of rare diseases.

The study led by Inserm US14 Director Ana Rath analyzed the prevalence of 3,585 rare diseases affecting the world’s population to come up with the results. Rare cancers, infections and poisoning were excluded from the study because they are already tracked in the U.S. and the researchers tried to seek out ‘rarer’ diseases plaguing the world.

Systemic sclerosis, polycythemia vera and Marfan syndrome are some of the obscure conditions studied, which the general public has no clue about. “Although rare diseases are individual and specific, what they have in common is their rarity, and the consequences which result from that," Rath said.

Among the 6,000 diseases accounted for in the Orphanet database, only 149 illnesses had affected 80 percent of the people diagnosed with rare diseases. Since faulty genes are the main cause behind most rare diseases, the researchers who had evaluated the diseases on Orphanet said that 71.9 percent of the diseases are genetic, while 69.9 percent had started in childhood.

“Future research must now focus on collecting and analyzing the data on the rare diseases which had been excluded from this study. Cancers and other rare diseases caused by infectious agents or linked to environmental factors will be the subject of new analyses,” the researchers stated in the paper.

“But the researchers' priority remains the same: namely, to broaden the field of knowledge on rare diseases in order to offer patients better treatment and ensure that, in the future, no-one is left behind,” they added.