As parents continue to shun the controversial triple jab despite mounting fears of a measles epidemic, Panorama asks how safe is MMR?

The government tells parents that MMR - the triple vaccine against Mumps, Measles and Rubella - will not harm their children. But many do not believe it.

Uptake of MMR has fallen dramatically since 1998 when controversial doctor Andrew Wakefield recommended the use of single vaccines.

Dr Wakefield says MMR should not be used until research rules out the possibility the triple jab could cause autism and bowel disease.

Conflicting research

In response, the government accused him of bad science. Last November Dr Wakefield left his post at the Royal Free Hospital claiming he had been told to stop his research.

Dr Andrew Wakefield

For the past year Panorama has followed the MMR controversy, filming Dr Wakefield at work, at home with his family and in America with his scientific collaborator - virus hunter Professor John O'Leary.

In an exclusive interview for Panorama, Professor O'Leary discusses his collaboration with Dr Wakefield and claims only further scientific research can resolve the MMR debate.

Panorama follows Dr Wakefield and Professor O'Leary as they present their research to some of the world's leading autism experts.

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

Families' stories

The programme tells the disturbing stories of three families who are all convinced their children developed autism as a result of MMR.

The parents of one boy, now 16-years-old, had his first MMR injection at the age of four and his second aged nine.

His parents claim he is the victim of a "double hit" that transformed their apparently normal toddler into a severely autistic boy who rarely speaks or eats.

Award-winning Panorama reporter Sarah Barclay sorts fact from fiction about the triple jab and asks what should the Government now do to avert a measles epidemic?

Production Team:
Reporter: Sarah Barclay
Producers: Gary Horne and Stephen Scott