Once again, the powers-that-be have released a study claiming to vindicate the MMR re: autism, with most of the mainstream media dutifully waddling behind, rubber-stamping and disseminating the conclusions.
And once again, many of us are responding with skepticism.
It does seem some things never change. Once again we must contend with the misuse of limited, epidemiological data to promote wide-ranging, unwarranted conclusions, conclusions which either ignore or dismiss contrary data, as if one study could ever do that. And, as seems to be the usual result, general acceptance of that misuse.
This most recent study, published in the New England Journal of Medicine (NEJM) and based on data from Denmark, alleges to show that MMR could not be related to autism. It concludes that there are no differences between those vaccinated and unvaccinated against MMR as to incidence of autistic and "other autistic-spectrum" disorders. (Never mind that there is no genuine control group, that is, unless no vaccine but MMR could possibly be involved.)
Maybe this study says something about autism in Denmark; maybe it doesn't. However, the important question for those not living in Denmark is, does the Danish study say anything about what is happening elsewhere?
The incidence of autism reported in the Danish study cohort appears to be considerably lower than what has been recently reported in the US and other countries - an incidence of 1 out of 727 (or 738 out of 537,303) compared, for instance, to an incidence as high as 1 in 86 among primary school children in the UK and around 1 out of 150 children in the United States. Is that because there are real differences in incidence between Denmark and these other countries? If not, is the Danish study missing hordes of autistic children? Or are we instead overestimating the numbers occurring in the U.S. and other places?
A recent M.I.N.D. Institute study revealed the increase in autism in California to be real and alarming. Are we to accept the Danish results and ignore what is happening in our own country which may contradict them?
If there are real differences in incidence between the US and Denmark, why might that be? One reasonable possibility relates to thimerosal use in Denmark - it has been reported that Danish children did not receive vaccines containing thimerosal. If that is true, and if, for instance, it is the combination of thimerosal and MMR which leads to autism, there might well be no indication of problems with MMR in Denmark, but evidence of considerable involvement of MMR in the US and other countries where thimerosal has been used.
Thus even if MMR alone does not cause autism, the NEJM study in no way acquits MMR in combination with other co-factors. Why are they acting as if it does?
To the contrary, if the incidence of autism in Denmark is actually lower than in the US, and thimerosal wasn't used in childhood vaccines during the study period, this study actually raises a red flag about the possibility that MMR and thimerosal acting together are responsible for the epidemic of autism in some countries, since an important potential co-factor was missing in Denmark. At least it suggests the need for further study.
Another disturbing trend is the rejection of biological evidence in favor of weak epidemiological evidence (e.g., see my review of one IOM report). Why are the study authors behaving as if their study results justify dismissing or ignoring the growing body of human biological evidence that MMR and autism are related? It is only a retrospective epidemiological study, after all. Why are they trying to use it to trump solid biological mechanisms data?
Moreover, if Danish children did not receive thimerosal, why wasn't the absence of it in this population noted, given its obvious import and relevance to any study concerning autism?
The NEJM study raises far more questions than answers. And it begs the questions, "Why aren't better studies being done?" and "How might such studies be designed?"
I can't say why better studies aren't being conducted. But were they to be done, they would be long-term and prospective. They would be large enough to allow comparison of all vaccination and other possibly relevant combinations, including a "never vaccinated" control group. They would track study participants from birth or before. All aspects of health and other history would be recorded. Confounding factors would be controlled for by matching the groups.
As clues to the possible cause(s) of autism emerged, investigation into possible biological mechanisms would follow. Just as Wakefield and others have done.
Make no mistake about it, though - I'm sick and tired of hearing how better studies are too difficult to manage. I don't care how hard it is to find never vaccinated children. I don't care how much it costs to follow large numbers of children, to prospectively track all adverse vaccine reactions, to study biological mechanisms in a way that translates into meaningful human data.
(And if you're thinking money is the problem, note the following statement by Congressman Shays, made in the April hearing on government funding of autism research: "Let me just say something, just so I can put this on the record. I don't fault administrators when we in Congress don't appropriate the money, but where administrators become responsible is when they see a need and they can fill a need, they don't request the money, and then we in Congress don't respond. I am getting the sense that in the last years this has been mostly generated by Congress kind of pushing NIH and others to treat this as a more important effort. I may be wrong, and I am happy to be corrected." Is Congressman Shays wrong? If not, why aren't NIH and the CDC treating this situation more seriously?)
I also don't care that confidence in vaccines might be undermined were studies to be designed properly. All public confidence has been based on the understanding that such studies had already been conducted. That confidence has now been thoroughly shaken.
I simply don't care about any of the excuses which are keeping well-designed epidemiologic and biological mechanism studies from being conducted.
The public has been told the MMR vaccine is safe and that is why they have used it. All the public cares about is getting information it can trust and Public Health owes it nothing less. Until and unless the hard work of properly designing and conducting studies is done, I and others will continue to question and challenge MMR vaccine study results, and question and challenge MMR vaccine use.
"Eternal vigilance is the price of liberty." - John Philpot Curran (1808)