What is a rare disease?

Rare disease UK , 2021.

‘The European Union defines a disease or condition as rare if it affects fewer than 1 in 2,000 people within the general population.’

‘The majority of rare diseases currently have no effective treatment.

8 out of 10 rare diseases have a genetic cause and 99% of genetic conditions are classed as rare. Often rare diseases are chronic and life-threatening. Rare diseases can be single gene, multifactorial, chromosomal or non-genetic.

On average, it takes over four years to receive an accurate diagnosis of a rare disease.’

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Additional information.

Sweet’s syndrome affects no more than 3 people per 10,000 (read more here). Unlike most autoinflammatory conditions it isn’t genetic, but people with Sweet’s syndrome, mainly Japanese, are more likely to have the genetic marker HLA-B54. It most commonly affects adults, particularly women, and only 5% to 8% of cases have been in children.

2012-present, Sweet’s Syndrome UK