Jeremy Laurance: A gamble that risks turning a maverick into a martyr

The General Medical Council's decision to pursue Andrew Wakefield is a huge gamble. The scare over MMR vaccine that began in 1998 has seen hundreds of thousands of parents reject one of the most basic safeguards for children.

In the eight years since, experience has shown that any publicity about MMR, even that which has undermined the credibility of the author of the scare, has damaged confidence in the the combined vaccine against measles, mumps and rubella and led to a further fall in immunisation rates. Bringing a disciplinary case against Dr Wakefield risks re-enforcing the view that there is a conspiracy by the Government and medical establishment to promote MMR. If the GMC wins, it could turn Dr Wakefield into a martyr. If it loses, it may reignite debate about the safety of the vaccine.

The case has been through the GMC's screening procedure and, despite initial scepticism as to whether it could be made to stick, lawyers on both sides now accept that he will be charged with serious professional misconduct.

His defenders say that his research may be open to criticism, like any research, but academic disagreement does not add up to serious professional misconduct. Even his failure to disclose a conflict of interest - that he was being paid by the Legal Aid Board - has been described by at least one senior GMC member as "foolish" but not unprecedented and not sufficient to justify charges by the GMC.

The question now is what effect a public hearing before the GMC will have on MMR vaccination rates. In the tentative view of the Health Protection Agency, public confidence in the vaccine is just beginning to return and immunisation rates are on the rise. It would be tragic if that were to be damaged.

The really surprising feature of the MMR scare has been not how it started but how it has been sustained for so long in the face of overwhelming evidence that the vaccine is safe.

The safety record of the combined triple vaccine is vastly superior to that for the single vaccines. Yet many parents have opted for single vaccines in preference to the triple MMR in the belief that they are protecting their children from a greater harm.

Why have intelligent people chosen to reject mainstream science and listen to far less authoritative sources? Unlike most scientific controversies which flare up and die away, this one has simmered on for eight years. It has been sustained by a mix of public anxiety, public mistrust of government assurances on health following the BSE debacle and sympathy for a lone doctor.

Growing environmental concerns about pollution, additives in the diet and genetically modified crops have conspired to undermine faith in science. Tony Blair's refusal to say whether his son Leo had received the MMR vaccine heightened anxiety.

Richard Horton, editor of The Lancet, which published the offending paper, has said the controversy over MMR revealed a society "unable to come to terms with dissent" and called it "a crisis of rationality." Whatever the outcome of the GMC case, rebuilding public confidence in science must be a priority in an age facing unquantifiable threats as diverse as those from global warming and avian flu.

But in the field of children's health, a constant source of anxiety for parents, nothing can compete with the power of anecdote. So it is worth recording that Professor John Walker-Smith, the distinguished paediatric gastroenterologist who was the senior author on Dr Wakefield's 1998 Lancet paper, disclosed in 2002 that he continued to support MMR - as have all the Royal Free paediatricians from the beginning - and that three of his own grandsons had had the triple MMR vaccination.