Lawyers have launched a class action on behalf of 38 Britons - including 19 children - who developed narcolepsy after having the swine flu vaccine.
In February, scientists from the Health Protection Agency (HPA) said there was evidence of a link between the Pandemrix jab - manufactured by GlaxoSmithKline (GSK) - and narcolepsy in children in England.
Its figures suggest about one in 55,000 children vaccinated - about 20 in the UK - are thought to have developed narcolepsy.
Lawyers Hodge Jones & Allen have now started legal action against GSK. It said compensation could be up to and possibly exceed £1m for each sufferer. The children who form part of the claim are now aged six to 16.
The move follows the government’s decision in September to confirm a link between Pandemrix and narcolepsy, paving the way for compensation claims through its Vaccine Damage Payments Scheme, run by the Department for Work and Pensions.
A letter from the Treasury to Hodge Jones & Allen said it will be dealing with the claim on behalf of GSK.
Hodge Jones & Allen said GSK had invoked a government indemnity agreed with the Department of Health which requires any compensation claims and costs to be paid out of government funds.
The Pandemrix vaccine was given to high-risk groups, including children and those with asthma, diabetes and heart disease, at the height of the 2009-10 swine flu pandemic.
Across Europe, about 31 million people are thought to have received the jab.
Narcolepsy is a rare but serious neurological disorder that affects about 31,000 people in Britain.
The condition can cause massive disruption to sleep and daily life, and some narcoleptics have another condition called cataplexy, which is a total loss of muscle control.
Peter Todd, a solicitor and partner at Hodge Jones & Allen, who is representing the UK families seeking compensation, said: “I did not expect GSK to invoke their entitlement to be indemnified by the UK government - however they have done so immediately after the UK government itself admitted a link between the vaccine and narcolepsy.
“This is a quite unprecedented situation.
“Narcolepsy is a serious, incurable condition requiring a lifetime of medication and management.
“Many of the activities that most people take for granted can be totally compromised, such as study, work and the ability to have sole care of young children. The innocent victims of this deserve support and provision for their futures.”
A new European Alliance has now been formed calling for a public inquiry in European Union states where the Pandemrix vaccine was used.
Around 800 children and young adults across Europe are thought to be affected by narcolepsy following vaccination.
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