Monday’s medical myth: the MMR vaccine causes autism

Case closed: the MMR vaccine has no relationship with autism.

Few medical myths have spread as feverishly and contributed to so much preventable illness than the theory that the triple measles, mumps, and rubella (MMR) vaccine might be linked to autism.

The tale was first suggested by Andrew Wakefield at a 1998 press conference following the publication of his now discredited (and retracted) Lancet paper.

The paper itself didn’t address such a connection but Wakefield raised concerns with journalists and called for a boycott of the MMR vaccine.

“I can’t support the continued use of these three vaccines, given in combination,” he said, “until this issue has been resolved.”

Wakefield said the vaccine should instead be broken into single components and given at yearly intervals.

We now know Wakefield had good reason to discredit the MMR: he had a patent for a single measles vaccine and he was being paid by lawyers who were assembling a case against MMR manufacturers.

None of these conflicts of interest were revealed when The Lancet paper was submitted for publication – if they were, it would never have been published. As the editor of the Lancet noted, Wakefield’s paper was “fatally flawed.”

Further investigation published this year in the British Medical Journal revealed what Wakefield did wasn’t just bad science, but deliberate fraud.

Andrew Wakefield’s actions were “callous, unethical and dishonest”. AAP

Wakefield was struck off the UK medical register in 2010 for “callous, unethical and dishonest” behaviour. But the damage had already been done.

A drop in MMR vaccination rates lead to inevitable outbreaks of preventable disease.

The episode also prompted research on possible links between MMR – and vaccines, in general – and autism. Now, 13 years after Wakefield’s paper was published, we have considerable evidence that MMR is not linked to autism.

One of the largest single studies to look for a link came from Denmark and covered all children born from January 1991 through December 1998. The study examined a total of 537,303 children, 82% of whom had been vaccinated for MMR.

It found no association between vaccination and the development of an autistic disorder.

More evidence comes from Japan, which stopped using the trivalent vaccine in 1993 over safety concerns with the anti-mumps component of the MMR formulation.

A study of more than 30,000 children found autism cases continued to rise even after the MMR was withdrawn and replaced with single vaccines, providing strong evidence that the MMR vaccine was not implicated.

Most recently, the United States Institute of Medicine completed an exhaustive review in August 2011 of all the scientific literature and concluded there was no causal relationship between MMR vaccine and autism.

So science has rejected such a link, but what have the courts found?

The US Court of Federal Claims (Vaccine Court) was established in 1988 as a no-fault system for litigating vaccine claims.

In 2007 the court began to hear the “autism omnibus” trials – a class action of almost 5,000 lawsuits attempting to demonstrate MMR played a causal role in the development of autism.

The group put forward the best three cases as a trial and the decision was handed down in 2010.

Judge Hasting wrote of one case, “Considering all of the evidence, I found that the petitioners have failed to demonstrate that … the MMR vaccine can contribute to causing either autism or gastrointestinal dysfunction.”

Patricia Campbell-Smith, special master on another case, said “The petitioners’ theory of vaccine-related causation is scientifically unsupportable.”

This myth has been well and truly busted.

Science still doesn’t know exactly what causes autism, but researchers are continuing to look.

In the meantime, it’s important parents get accurate information about vaccines so they can protect their kids from preventable disease and avoid getting taken in by expensive and dangerous quack therapies.

Who knows, if we hadn’t been sent on a wild goose chase by the nefarious research of Andrew Wakefield we might be closer to understanding this syndrome.

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