A KEYNSHAM couple who claim a vaccine jab caused their son's autism have launched a legal battle against a drugs manufacturer.

Richard and Jane Denning took their son Steven, who is now ten, for a measles, mumps and rubella vaccination when he was a baby.

But they claim it left him trapped in a world of silence, unable to speak and interested only in repetitive physical games.

Steven had the jab at the age of 14 months. He was diagnosed with autism when he was three.

Now he shuns the normal activities of children his age, preferring long, solitary sessions bouncing on his indoor trampoline. He does not even watch television.

After years of anguish trying to come to terms with what they call Steven's "lost life", Mr and Mrs Denning are convinced the MMR jab was to blame and have launched a legal battle against the drug's manufacturer, Pasteur Merieux.

Mrs Denning, 49, said: "Up until he had the MMR he was perfectly normal. Then he started to go backwards. He will never live an independent life."

Steven has been granted legal aid and the solicitors acting for him have filed a High Court writ against Pasteur Merieux, claiming damages of more than £50,000.

Local government officer Mr Denning, 50, said: "The first year of his life was perfectly normal. But after the jab he started to regress. He had some speech, but he lost it and his play became very repetitive.

"We feel the triple vaccine is too strong for many children and they should go back to the single doses a year apart that they used before MMR.

"We would really like a major independent inquiry into MMR, but our only recourse at the moment is to sue the manufacturers.

"We are doing this for Steven's future. With the best will in the world, the education service cannot provide everything that he could possibly use. We want his quality of life to be maintained."

When not being cared for at home, Steven attends a special school and he spends one night a week in a respite home. The couple's other child, Joanne, 14, did not have the triple vaccine and is perfectly healthy.

The writ is one of a number filed by Alexander Harris solicitors. The firm has been contacted by more than 2,000 parents about MMR. More than 550 families are taking legal action.

The London firm's Emma Smith said: "We are hearing on average from a dozen families a week who feel their children have suffered injuries because of the MMR vaccine."

Over 27 years, 300 million doses of MMR vaccine have been distributed worldwide. In Britain, 1.2 million children receive it every year.

A spokeswoman for Pasteur Merieux said: "The World Health Organisation, the Medical Research Council and the Committee on Safety of Medicines have reviewed all the available data and stated that there is no evidence to suggest any link between MMR vaccine and any alleged disorders.