What Do Autism and Global Climate Change Have in Common?

On several major issues of the times, the community of scientists trained in the relevant fields has come to one conclusion and yet significant numbers of people continue to believe the opposite conclusion. I began to ponder this effect in the wake of the recent retraction of a scientific paper that was published in a respected medical journal in 1998 which suggested a possible link between the MMR (mumps, measles, rubella) vaccine and autism. That article was probably the spark that ignited widespread fear among parents of the vaccine which persists today. But the fact that many larger scale independent studies were conducted since that paper and found no such link did not help allay these fears. Why not?

I couldn't help but wonder if the mechanisms driving this disconnect between science and common belief were similar to those driving the rampant skepticism about global climate change science. My conclusion is there are similarities and differences in the two. The similarities include: (1) the way most people get the information on public policy issues, and (2) the effect of money and influence.

In the case of the vaccine fear, even though a respected medical journal (the Lancet) did publish an article raising the possibility of a link between autism and the MMR vaccine I suspect that very few of the people who feared the vaccine knew about that article and even fewer actually read it. No, their fear derived from sources such as inflammatory talk radio shows that echo stories about parents who said their children were diagnosed with autism soon after getting vaccinated. They might have also heard about someone who knew someone whose child had that happen. Word-of-mouth spreading of such tales gives an inflated impression of the number of such cases. They also heard statistics showing that the rate of autism diagnoses was increasing dramatically over the last several years - and guess what, so was the number of kids getting vaccinated! Hmm.

Of course none of these isolated facts are rational, scientifically valid reasons to jump to the conclusion that the vaccines caused the autism. The fact is, autism diagnoses have always occurred at about the same age that vaccines tend to be given so of course they will occur in close proximity and that in no way proves a causal link. And the increasing prevalence of autism diagnoses does not match up with the introduction of the vaccines as well as some would think. The fact is that many other things were increasing at the same time, so why attribute it to the vaccine? Two such factors that I have seen suggested for explaining the increase in autism diagnoses are: (1) Women are bearing children later in life, which is known to increase the odds of genetic diseases; and (2) Autism is diagnosed more readily-- even the definition of autism is being expanded to include behaviors that were not previously called autism.

But there is no need to speculate on these causes! Independent studies that look at large numbers of kids and sort out which ones got the vaccine and which ones didn't and then look at the rate of autism in each group are the best way to determine if a possible link exists. And guess what - such studies have been done and showed no evidence of a link! But do these fearful parents hear about such studies? If they do, will they process that information rationally? Apparently many do not. The talk radio source of their information is unfortunately biased toward the inflammatory, controversial bits of information. There is a simple reason for that-the purpose of these programs in not to inform but rather to entertain, and the motivation of the radio stations that put the programs on is profit. Profit is driven by ratings, and fear and controversy improves ratings. (By the way-a plug for public radio: their purpose IS to inform, so maybe we should listen to them more and commercial talk radio less!)

In the case of the vaccine fear, money had an even more insidious effect than merely driving talk radio hype. In the news about the retraction of the Lancet article it was revealed that the author was being paid by a law firm suing a vaccine maker - a suit that would benefit from casting doubt on the safety of the vaccine. Such conflicts of interest are supposed to be clearly listed with any article published in a scientific journal, but this one was not. But that wasn't even the main reason for the retraction - it was rather the flawed scientific methods used in the study and the fact that the evidence shown did not even support the conclusion given.

Perhaps ironically, many of the vaccine fear-mongers attribute a financial motivation to the scientific studies that show no link to autism. They point out correctly that 'there is a lot of money to be made' in selling vaccines. That is why I too would be skeptical of studies funded by the vaccine makers, but the fact is that many of the major studies reaching the same conclusion were not funded by the industry but rather by independent government agencies or non-profit groups! Of course there will always be 'conspiracy theorists' who think that even those agencies are corrupted by some mysterious evil power...

In the case of skepticism and outright hostile rejection of scientific conclusions related to climate change, talk radio and other mis-informed sources may have a role but there is another insidious money-driven factor: major corporations and industries that fear reduced profits from policies to address global change are actually funding organizations that actively attempt to discredit the science of global warming. These groups are given names that make them sound respectable, scientific, or even environmentally benevolent when their true aims are often contrary to these qualities. A good summary of some of these groups, which follows the money funding them, can be found here. Of course the primary industry doing the funding is the oil industry, with Exxon Mobil being a major player in these activities despite their green-sounding public advertising.

So when you hear inflammatory arguments that seem contrary to conclusions attributed to mainstream science, be thoughtful about it and consider the source! The source may be biased, or influenced by others who are driven by financial motivations. Follow the money.

Sources:

Bandolier, "MMR Vaccine," http://www.medicine.ox.ac.uk/bandolier/band84/MMR.html, accessed Feb. 11, 2010.

Wikipedia, the free encyclopedia, "MMR vaccine controversy," http://en.wikipedia.org/wiki/MMR_vaccine_controversy, accessed Feb. 11, 2010.

The Guardian, "ExxonMobil continuing to fund climate sceptic groups, records show," July 1, 2009.

Union of Concerned Scientists, "Global Warming Skeptic Organizations," http://www.ucsusa.org/global_warming/science_and_impacts/global_warming_contrarians/global-warming-skeptic.html, accessed Feb. 11, 2010.

Bloomberg, "Lancet Retracts Study Tying Child Vaccine to Autism," Feb 2, 2010, http://www.bloomberg.com/apps/news?pid=20601102&sid=aaLbZ1n4.rDw .