Juvenile Idiopathic Arthritis or JIA affects about one in a thousand children and young people.
In most cases we do not know what has caused it or how long it lasts for those people affected by JIA.
The arthritis may go away after some months or years or may carry on into adult life.
At the moment we cannot tell who will recover and who will have more long-term problems.
The causes of JIA are likely to be a complex mixture of genetics and other influences, but we need more research to help us to understand what causes JIA and the best treatments for children and young people who have JIA.