Andrew Wakefield

Wakefield first publicly claimed MMR may not be safe in 1998, and recommended the use of single vaccines.

Since he voiced these safety concerns the uptake of MMR has fallen dramatically leaving more children unvaccinated against measles, which in extreme cases can prove fatal.

It has taken more than a year for Wakefield's latest research to be published - a year during which successions of studies have denied any link between MMR and autism.

Despite failing to prove the MMR vaccine may harm children, Mr Wakefield is still convinced the triple jab may cause autism or bowel disease in some children.

He told Panorama: "You do not combine three live viruses into one vaccine and assume that it is a benign process.

"These are viruses that are live, they are capable of establishing long term infection and they are capable of producing long-term adverse events."

However the UK Government insists the triple vaccine is safe, and will not offer parents the choice to opt for single vaccines.

Deputy Chief Medical Officer Dr Pat Troop says: "If we were to offer single vaccines it would suggest to parents that there was a problem with the vaccine [MMR], we would end up with fewer children vaccinated rather than more.

"There may be some who might come forward for single vaccines but I think many more parents would just turn away from the vaccine and...we would have many more children exposed to serious diseases."

As the MMR controversy continues Downing Street has again refused to confirm reports that Tony Blair's son Leo has been given the MMR vaccine.