Vaccines do not cause autism.
The science proving this point has been quite clear for a number of years. But last week, the scientific evidence was given an important legal booster shot.
Judges at the U.S. "vaccine court" ruled on three test cases in which it was claimed that the standard childhood vaccine for measles, mumps and rubella caused autism, and they were unequivocal in their findings.
One judge (known by the title special master), George Hastings, said a thorough, dispassionate review of the evidence demonstrated that the vaccine-autism theory was "very wrong."
He said parents who adhere to this theory "have been misled by physicians who are guilty ... of gross medical misjudgment."
Special master Denise Vowell, who heard a case alleging that a mercury-based preservative called thimerosal can trigger autism, said that while the evidence is incredibly complex, the experts arguing that there is no link between autism and vaccines "were far more qualified, better supported by the weight of scientific research and authority, and simply more persuasive on nearly every point in contention." (Thimerosal was once used in childhood vaccines,+ but is no longer.)
Special master Patricia Campbell-Smith, who heard the third test case, said that while one cannot help but be "moved as a person and as a parent" by the tragic stories of children with autism, there is simply no credible scientific evidence demonstrating a vaccine-autism link.
The judges considered 5,000 pages of testimony from experts and 939 scientific articles and independently came to the same conclusion.
The rulings from the "vaccine court" - which was set up as part of a U.S. program to compensate people who suffer the occasional side effects of vaccines (Canada, with the exception of Quebec, does not have a compensation program for those harmed by vaccines) - effectively puts an end to the cases of about 4,800 families claiming their children's autism was caused by the MMR vaccine.
Unfortunately, it is unlikely to put an end to unsubstantiated claims about the MMR vaccine and childhood vaccines more generally.
That's because a whole industry of hucksters has sprung up to promote alternatives to vaccines, and the vocal (and Web-savvy) minority of conspiracy theorists will see these thorough, thoughtful rulings as, well, just another part of the conspiracy by Big Pharma to poison kids for profit.
The vaccine-autism scare dates back a decade. In 1998, British gastroenterologist Andrew Wakefield and colleagues published a now-infamous article in The Lancet medical journal that suggested a jab of MMR could trigger bowel conditions in children that led to autism. The study of 12 children caused a furor, but the findings have never been reproduced or substantiated. A number of Dr. Wakefield's co-authors have retracted parts of the paper and others are facing professional misconduct charges.
The damage has been incredible. In Britain, about 25 per cent of children do not get the MMR vaccine and, as a result, there has been a resurgence of childhood illnesses such as measles.
In Canada, we are not there yet but the vaccine-autism claims have fuelled an international anti-vaccine movement. It is a movement that relies on half-truths to peddle "alternatives" such as mega-doses of vitamins, homeopathic medicines and sham autism treatments.
Yet the reason this movement has flourished is that public-health officials have been incredibly inept at promoting the benefits of vaccination and even worse at answering parents' legitimate concerns.
The reality is that vaccines, and childhood vaccines in particular, are one of the greatest medical advances in the history of humanity.
The virtual elimination of once-common conditions such as measles, mumps and diphtheria through childhood immunization programs has prevented thousands of deaths and untold suffering.
But vaccination programs have been a victim of their own success. Polio and smallpox are all but eradicated, and so uncommon now are diseases such as measles that the public has lost sight of the devastation they wrought.
The reality, too, is that all drugs have side effects and vaccines are no exception. Childhood vaccines - and Canadian kids now routinely get shots to protect them from 14 illnesses - require bothersome needle sticks and they can cause fever and irritation. In rare instances, vaccines can cause shock, brain inflammation and death, particularly in children with allergies or compromised immune systems.
But the risk needs to be kept in perspective: Of the 400,000 children born in Canada each year - virtually all of those are vaccinated - about five will have severe reactions.
That makes vaccines many times safer than over-the-counter medications such as Aspirin and Tylenol.
And the ultimate tragic irony in all this is that the MMR vaccine is probably the safest of all.
Since the 1970s, more than half a billion doses of MMR have been administered around the world, and international research has concluded that there have been no deaths and no permanent damage caused by the vaccine.
Parents should have these reassuring facts in plain language from health care professionals and public-health programs, not be dependent on massive court rulings or, worse yet, the alarmist dreck on the Web.