OXFORD University has insisted an additive being used in a swine flu vaccination trial involving for young children is completely safe.

Concern has been raised over the use of Thiomersal – a mercury preservative – in one of the vaccines being tested on children aged between six months and 12 years.

Its use caused a health scare in America and it was withdrawn from use in childhood vaccines in the UK in 2004.

However, health officials have insisted there was no evidence that Thiomersal was harmful or had any link to adverse neurological affects, including autism.

Oxford University has been recruiting children locally for the vaccine trials.

But an Oxford father said the trials should be halted until more research was conducted into the safety of Thiomersal.

Tony Bateson said he was convinced his daughter Claire, who is now in her 40s and needs round-the-clock care, developed autism after being given diphtheria, tetanus and whooping cough jabs in 1964, when she was three months old.

Mr Bateson, 76, of Woodstock Close, North Oxford, said: “Of course it’s essential vaccines should be fully tested before populations are exposed to these materials.

“In this case, however, the test group is to include large numbers of infants and I’m concerned.

“The unprecedented withdrawal of Thiomersal, at little more than three weeks’ notice, has never been properly explained by the Department of Health.

“The use of Thiomersal in the UK in vaccines seemed to parallel the increase in recent years of autism conditions.”

“It also remains unexplained why, when some 10 to 15 per cent of UK infants over many years have not had any infant vaccines, this sizeable number does not seem to contain any autistic individuals.

“Until this doubt is fully answered, there should be no use of Thiomersal-containing vaccines whatsoever.”

The trial in Oxford is seeking 250 children. Tests will also take place in Exeter, Bristol, Southampton and London, with 1,000 children involved.

The study, being conducted with the Health Protection Agency, is funded by the NHS National Institute for Health Research.

A spokesman for Oxford University said: “There are two vaccines being used in this study. These are the vaccines that have been purchased by the Department of Health to protect the public and control the expected flu outbreak this autumn.

“Panderix contains Thiomersal, Celvepan does not.

“Thiomersal has been used for more than 60 years. It prevents bacterial contamination and there’s no credible evidence linking it to adverse neurological affects, including autism.

“It would be irresponsible to suggest that a vaccine would be used without careful consideration of safety issues.”

A Department of Health spokesman added: “There are no safety issues with Thiomersal in vaccines. Scientists have investigated and no evidence of harm has been found.”

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