Delays in diagnosis mean that new cases are coming forward all the time – two new cases were diagnosed only last week.
"We are distressed and angry at the minister's response," said Mary Fitzpatrick of Sound – the organisation that has been set up by the parents.
"It is almost a year since the publication of the Government report which promised us a package of support measures by the beginning of last summer. We are still waiting."
Mary said the group had recently asked for a meeting with the minister – only to be told that "due to a very busy schedule with both governmental and departmental business" the minister was "not in a position at present to accede" to their request.
Mary added: "He could at least meet us and listen to our concerns. We are in limbo. A lot of people are finding it very difficult." Children damaged by the vaccine suffer from narcolepsy, which means they fall asleep in an instant many times a day and have no control over this.
For many children, the condition also includes horrific, violent hallucinations every time they fall asleep or wake up.
Some also suffer from an associated condition called catoplexy, which is triggered by any kind of emotion – even laughing – where they suddenly lose the use of their limbs and completely collapse.
Mary, whose own son has narcolepsy, said: "This condition has no cure. They have it for life. It impacts daily on the person and the wider family. Medication can only relieve some of the symptoms."
She explained that, at present, all the sufferers only have temporary medical cards.
And while those at primary and secondary school are given education supports, young people who have left school are struggling.
"They can't get a job because of their condition and, if they want to do a college course, they would need to live on campus because they fall asleep on buses."
Mary said there are still huge delays in diagnosing the condition because GPs are still not familiar with the symptoms.
"We had two new cases diagnosed last week and I was contacted by another person as recently as yesterday."
The group wants "guaranteed full medical cover, a pension or support for people who can't work, allowances for parents who have had to give up work to look after children."
They are now so angered by the minister's attitude that they are holding meetings to launch a protest campaign to demand immediate action.