Oct 08 2009

More Vaccine-Autism Nonsense

The anti-vaccine community is tireless. As I wrote yesterday, they happily shift around their multiple goalposts as long as they have some working hypothesis about how vaccines are to blame for autism or some human suffering. They have moved from MMR to thimerosal to aluminum to “toxins” to squalene and now the HepB vaccine. They just spin the wheel and choose their next target – although they never really abandon their prior targets, they just back burner them a bit.

They also have their small dedicated group of researchers, like the father and son team of Geier and Geier, to produce crappy studies to support their anti-vaccine claims. Andrew Wakefield, who has been rightly vilified for starting the MMR scare with his now discredited Lancet study, has also apparently decided to make a career out of feeding bad studies to the anti-vaccinationists.

I acknowledge there is a certain symmetry to the situation now. The scientific community presents studies that show a lack of correlation between some aspect of vaccines and autism or other neurological disorders. They generally accept these studies as supporting vaccine safety, even while being open about their limitations. They also sharply criticize those studies that suggest there may be a connection between vaccines and autism as fatally flawed.

Meanwhile, the anti-vaccine community rejects and dismisses all studies that show vaccine safety, while uncritically accepting any study that can be used to argue for vaccine toxicity. To the outside observer this can all seem like a he-said, she-said situation. And of course, that’s the point. To create the public appearance of a legitimate controversy, knowing that much of the public will take the position that they think is erring on the side of caution (really fear). Fear is easier to promote than reason.

The same thing happened with regard to tobacco and lung cancer (although in the other direction) – while the science was showing a link, the tobacco industry did everything they could to cast doubt on these conclusions, hoping to muddy the waters and confuse the public.

In order to sort the situation, the only option is to actually look at each study as objectively as possible – the answer is in the details of the analysis of each study. This is a daunting task for any individual, let alone someone who is not a medical scientist, and so generally the public will simply decide which side is more credible and listen to them. This is precisely why the anti-vaccine movement spends so much time attacking the credibility of anyone who disagrees with their hysteria.

The latest round is over a recent monkey study that was designed by none other than Andrew Wakefield and others with an anti-vaccine agenda. For me, that fact alone calls the study into serious questions – Wakefield is still under a cloud of accused fraud over his original Lancet study (which in any case is a discredited study). Fraud in scientific research, in my opinion, is not something you can get past. It disqualifies you for future research. The integrity of the scientific literature is just too important.

But even if we put Wakefield’s involvement aside, the study attempting to link the HepB vaccine to neurological delay in monkeys, is a terrible study. David Gorski has already done a detailed analysis at Science-Based Medicine, so I will not repeat it, just read his post.

One of the main points is the hypocrisy of the anti-vaccine crowd. Age of Autism wrote a glowing review of the monkey study, dismissing any suggestion that conflict of interest may have affected the outcome of the study. Meanwhile, they use even the slightest appearance of a COI to dismiss any study which does not support a link between vaccines and autism, and yet they ignore the massive actual COIs in this study. Wakefield was paid vast sums of money by trial lawyers to find a link between MMR and autism. That’s OK with AoA, who will dismiss a study simply because it was funded by the CDC.

COIs aside, the study has major flaws. They found a delay in the appearance of neurological milestones in monkeys who had been given the HepB vaccine compared to placebo. However, the numbers in the study were very small, and not balanced – there were only 13 monkeys in the vaccine group, four receiving saline injection, and three getting no injection. Further, the authors assume without justification that the milestones they are assessing are a meaningful marker of ultimate neurological development in monkeys, let alone humans.This is exacerbated by the fact that the monkeys were followed for only two weeks. (As far as we know – it is quite possible we are being fed a small subset of the actual data, as David Gorski explains).

David brings up many more dire concerns about this study, such as the fact that monkeys were assigned to groups on a “semi-random” basis. What? Semi-random sounds an awful lot like non-random, which (given the small numbers) could produce just about any result you wish.

In short, this is a terrible and suspect study that tells us nothing about the association of vaccines and autism. It’s only purpose is to give another round of press coverage to anti-vaccine propaganda.

Meanwhile, the evidence overwhelmingly supports the conclusion that vaccines are safe, there is no real increase in autism incidence, and vaccines do not cause autism.

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