A new support group has been launched for children suffering from a chronic sleep disorder linked to one of the vaccines used to ward off swine flu in 2009 and 2010.

Called SOUND – which stands for Sufferers of Unique Narcolepsy Disorder - the group aims to help parents identify if their children have been affected by the condition and provide them with help if they have.

So far 30 cases of narcolepsy have been identified by the HSE, which said it has now put arrangements in place for speedy tests and diagnosis.

A possible link between narcolepsy and the Pandemrix vaccine, which is no longer on offer here and has been recommended for restricted use only by the European Medicines Agency, is currently being investigated.

Scandinavian studies have already indicated a link between the flu vaccine and a rise in narcolepsy in children.

There's no cure although medicine helps.

The HSE says it will support those affected but hopes the matter will not put people off having vaccinations.