Parents have no cause for alarm as this scare is based on flawed research

Dr Wakefield is on a crusade. In the past, he has asserted that the measles vaccine causes bowel disease and linked MMR to autism, and now that MMR was licensed without proper safety studies.

Dr Wakefield is on a crusade. In the past, he has asserted that the measles vaccine causes bowel disease and linked MMR to autism, and now that MMR was licensed without proper safety studies.

Before we look at his recent claims, we need to remember that he has been wrong before, and his views have no support from experts in vaccines. We also need to recognise that this is not a problem faced by the UK alone. MMR is used all over the world, and it is likely that the US, Canada, Australia and other countries made their decisions on the same data. So were they all wrong, or is Dr Wakefield wrong? The evidence points to MMR having an excellent safety and efficacy record in use, with hundreds of millions of doses used.

In his new paper, Dr Wakefield appears not to know the facts, and fails to report all the evidence. He gives the wrong dates when vaccines were licensed, he misleads readers over just how long follow-up studies really took place, and he uses wrong statistical analyses.

He raises scares about MMR safety, such as possible problems from giving three viruses together. Here he uses the example of the rare but terrible brain-damaging condition SSPE that results from measles - possibly made worse if another infection occurs with it. But the evidence is clear: measles vaccine protects against SSPE, and US and UK data show the condition became even rarer after the switch to MMR. Parents should be reassured that even if this scare had a theoretical basis, in reality the evidence supports MMR.

When Dr Wakefield sent us his paper challenging MMR safety, we asked our two independent expert committees to review it. The Joint Committee on Vaccination and Immunisation concluded that "reports from Dr Wakefield's group did not give grounds for concern over the safety of the vaccine", and noted inconsistencies, the lack of rigorous logic and the failure of confirmation by a wide range of independent investigators. The committee concluded that the analyses carried out by Drs Wakefield and Montgomery were intrinsically flawed." The Committee on Safety of Medicine also looked at the paper, especially to check that the licensing had been sound. It concluded that the process was properly conducted and that the licensing followed normal procedure and was based on robust studies.

Dr Wakefield wants more research. Independent researchers have not replicated his studies on vaccines across the world. In Japan, measles and rubella vaccines are given separately. From 1992 to 1997, there were 79 deaths from measles. Here, there were none. Yet Dr Wakefield wants us to risk children's lives without a shred of evidence. Children's health is too important to became a victim to his crusade.

David Salisbury is head of immunisation at the Department of Health