But more and more research groups, with more sophisticated techniques, failed to confirm Wakefield's findings. In 1998, the chief medical officer from the U.K. Department of Health and a group of experts reviewed Wakefield's studies and concluded that the there was no support for a causal role for the measles virus infection in Crohn's disease. Furthermore, they found that there was no link between the MMR vaccine and bowel disease. In 2000, the U.K. Medical Research Council also conducted a review and came to the same conclusion, as did a Japanese research group: "We failed to detect any measles virus genome or measles virus antigen in gut tissue from patients with [inflammatory bowel disease]," the authors stated. So Wakefield abandoned his initial theory on Crohn's disease and measles.

In 1996, just as Wakefield began to get hit with fierce criticism about his Crohn's claims—culminating in a British TV program called The Big Story—along came a solicitor, Richard Barr, who was representing parents who believed that their children had been harmed by the MMR vaccine. Investigations by journalist Brian Deer in the Sunday Times questioned Wakefield's conflicts of interest in the Lancet study, and he reported that Barr was desperately looking for some scientific basis for claims that the MMR vaccine caused a wide range of adverse effects, including bowel and developmental disorders. It later transpired in the General Medical Council hearing, as Deer had previously reported, that Barr had paid Wakefield nearly 450,000 pounds with money from the U.K. legal aid fund to conduct his 1998 Lancet study, all financial conflicts that he never declared to the Lancet.

His failure to establish a link between the vaccine and Crohn's link did not teach Wakefield to think smaller: Soon after meeting Barr, his ideas became bigger and more complicated, and he had now "discovered" a new link between the MMR shot and autism.

Michael Fitzpatrick, a general practioner who is the father of a boy with autism as well as the author of MMR and Autism: What Parents Need To Know, explains Wakefield's new four-stage theory: 1) The measles virus or vaccine caused persistent infection, which became localised in the bowel; 2) the patient went on to develop inflammatory bowel disease, which resulted in a leaky bowel; 3) the leaky bowel allowed toxic peptides to get into the bloodstream, 4) which reached the brain and resulted in autism. Wakefield even went on to announce a "new" disorder associated with the MMR vaccine. He labeled it "autistic enterocolitis"—but it is still not recognized in the gastroenterology field.

Sadly, despite scientific evidence, some parents of autistic children still hang onto Wakefield's every word and will continue to support him. "Led by the pharmaceutical companies and their well-compensated spokespeople, Dr. Wakefield is being vilified through a well-orchestrated smear campaign," Jenny McCarthy claimed when the Lancet withdrew the MMR-autism study. Wakefield seemed to think that people who did not accept his theories had a personal vendetta against him. "This was a recurrent feature of Wakefield's approach to research," said Fitzpatrick. "He could not accept evidence that contradicted his hypothesis, which became a conviction sustained by faith in face of the evidence."

But why did the autism idea stick when the Crohn's theory never did? Tom MacDonald notes that autism is very difficult to study, while Crohn's researchers can actively take samples, and patients are available for assessment. "However," he says, "no one can get into the gut of autistic kids because it is unethical."

It looks like Wakefield has found his key audience and supporters in the United States, where he is now based. As he continues to tour the United States, telling parents that "the scientific system has failed you," real scientists will continue to endeavour to use appropriate research methods to try and find the cause or causes of autism.

"Once a crook," Ingvar Bjarnason, professor of digestive diseases and consultant physician at King's College Hospital, says of Wakefield, "always a crook."

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