Hard Conversations: Vaccines and Autism, Part 2
So where did this hype about autism and vaccines come from?
In 1998 Andrew Wakefield published a case series of 12 children who had behavioral problems including autism (9 of the patients), and also gastrointestinal problems. In all except but 2 cases, the parents said that the onset of behavioral problems was around the same time as the MMR vaccination. He took these children and did a bunch of testing on them including colonoscopy with biopsy, lumbar puncture, EEG, MRI, and a bunch of lab studies on their blood/serum. All the children had something abnormal on colonoscopy – but not necessarily the same thing in any of them, just something.
So firstly, do we all remember where case series are on our evidence scale? They were right near the bottom, just over expert opinion. This is exactly why. Wakefield cherry picked 12 children with ASD (which we have described as relatively common) and linked them with gastrointestinal problems. How often has your child, ASD or not, had gastrointestinal problems?
Based on this, not at all convincing evidence, Wakefield called for a suspension of the MMR vaccine, claiming that somehow these GI findings provide a mechanism for autism to be caused by autoimmune disease (There is a lot of hand waving here, I can’t even make it sound more reasonable than this if I tried). But the evidence never showed bore this out; in fact, large studies in both Europe and here show no correlation between MMR and ASD. The Institute of Medicine and the Cochrane collaboration also failed to find any such link.
In kind of a follow up to this study Wakefield and his collaborators put up a couple of studies showing that you could get measles virus from the intestines, and/or blood cells of ASD patients with GI problems. I won’t get into detail except that to say the labs where these studies were done were subsequently plagued with contamination problems. No one could replicate those results.
A key to science is replication of results. We believe gravity because I know, I can always drop an apple, and it will always hit the ground. The results from Wakefield’s studies have so far been not replicable, only Wakefield and his collaborators can get those results. Studies using more accurate technology have pretty definitively ruled this theory out; you can’t find measles in a patient vaccinated with MMR, that’s not related to the cause of ASD.
Now here’s the ironic kicker: often advocates of Wakefield’s position often accuse people who disagree with them of being paid off by Big Pharma, something one blogger has described as “the pharma shill gambit.” However, Andrew Wakefield, in 1997 filed a patent for a vaccine that would have been a competitor to MMR. Additionally it turns out, some parents in the original study were working with lawyers to sue the manufacturers of the MMR vaccine, and the UK legal aid board paid 55,000 pounds to help fund the research in that Lancet article. If that wasn’t enough, Wakefield was personally given 400,000 pounds by the lawyers in the MMR suit. Currently, Wakefield is being investigated for professional misconduct for all the shady activities in this sad story.
But wait, we’re not done – despite the fact that we still have no initial reason to suspect vaccines aren’t safe, since the article purporting that link was just revealed to be pretty fraudulent the anti-vaccine advocates said “well ok, Wakefield may be wrong, but let’s try again.” The next question raised was about thimerosal, a mercury containing preservative used in some vaccines. It was pointed out in the discussion of part 1, that MMR never contained thimerosal. Mercury is bad right? Let’s just take it out and not worry about it. That’s exactly what the FDA did, they called for the removal of thimerosal, and it has been removed. This is important: no one ever proved thimerosal does anything bad. They took it out. Since it’s been removed, other studies have shown the rate of autism continues to climb. Which simply wouldn’t be the case if thimerosal was to blame.
A small side note: in the discussion on part 1, someone said that there might be “trace” amounts of mercury still in vaccines – there’s no reason for that to be true, any more than there should be trace amounts of cyanide, or trace amounts of gold in vaccines. And even if there were trace amounts of mercury in vaccines, so what? The dose makes the poison, we encounter mercury in everyday life in higher doses than “trace” amounts, among other places in seafood.
This post is primarily a summary with discussion of “Autism Spectrum Disorder : No causal relationship with vaccines”, so rather than post a reference to each individual study they reference, I have reposted the reference to the review article, and Wakefield’s Lancet article.
Link to part 3 here.
On Deck: a quick wrapup of one last hypothesis for vaccine-autism connection, “Vaccine overload.”
In the pipeline: A discussion of why Hannah Poling doesn’t mean every ASD child has a mitochondrial disease.
For those who hit their saturation point on autism: Once we wrap up this series of posts, I’ll intersperse some more personal stories, hopefully some fun things, and “cool science” instead of just serious things, but the next series of Hard Conversations will either be about Naturopathic medicine, TCM/acupuncture, or chiropractics . Please email me if you have any specific thoughts on which one should be next, it’ll either be by popular demand or whatever has the most interesting articles in the popular press when I’m ready to tackle it.
One more sidenote: Someone appropriately pointed out that the comments swiftly leave the realm of “can be understood by a layperson”. I’ll endevour to steer the discussion back in the “clear and understandable” direction when I can.