Table of Contents
Introduction
On December 11, 2018, Mark Green, a member-elect of the US House of Representatives from Tennessee and a physician, told a town hall audience, “Let me say this about autism. I have committed to people in my community, up in Montgomery County, to stand on the CDC’s desk and get the real data on vaccines. Because there is some concern that the rise in autism is the result of the preservatives that are in our vaccines.”
By saying that he intended to push the CDC on the question of whether vaccines—and specifically the mercury-containing preservative thimerosal—might be contributing to the autism epidemic, Green committed the sin of heresy against the vaccine religion, and the mainstream corporate media was quick to attack him for it. The suggestion that vaccines might cause autism is “baseless”, declared CBS News. Green made the claim “falsely”, declared CNN.
The website FactCheck.org also dutifully got in on the act with an article by Jessica McDonald stating that Green “inaccurately claimed that vaccine preservatives might cause autism.” His statement, McDonald writes, was “bogus”.
To counter Green’s ostensibly “bogus” claim, McDonald writes (bold emphasis added):
Multiple large studies already have investigated whether any aspect of vaccination — including preservatives — can cause autism and found no evidence they do. The CDC alone has conducted nine investigations into the preservative thimerosal, finding no link to the disease….
Green’s suggestion that vaccine preservatives could be behind the “rise in autism” is not backed by science.
As the CDC says on its website, “there is no link between vaccines and autism,” and “vaccine ingredients do not cause autism.” And in fact, as we have written before, it is not necessarily clear that there has been a rise in autism. There certainly have been more reported cases in recent years, but during that time the definition expanded and awareness increased.
Then McDonald explains that the concern about thimerosal is the fact that it contains mercury. Specifically, thimerosal is about half ethylmercury by weight and is used in multi-dose vials of vaccines to prevent contamination. It was included in numerous childhood vaccines until the decision was made in 1999 to remove it from most. It is still used in multi-dose flu vaccines, which the CDC recommends for children as young as six months as well as pregnant women.
After explaining that the concern is related to the use of mercury in vaccines, McDonald continues (emphasis added):
Although the phrase “mercury-containing” might sound scary, thimerosal has a stellar safety record. Not only is the amount of mercury in a vaccine extremely small, but it’s also a type known as ethylmercury. This type of mercury is different from methylmercury, which is the form that accumulates in fish and is toxic to people. Ethylmercury is broken down in the body much more quickly, so it poses less of a risk.
The thimerosal in vaccines is only thought to be dangerous if a person has an allergy to the chemical, and that’s rare. The side effects are minor: a little bit of redness and swelling at a vaccine injection site.
I have preserved McDonald’s links to her sources in the above quotes from her FactCheck.org article. As you can see, so far, she has relied entirely on information the CDC presents to the public on its website—apart from the suggestion that the increase in autism prevalence is a statistical artifact, not real, which we’ll come back to.
You can click the links and verify for yourself that she is representing the CDC’s information accurately.
After taking the CDC’s word for it that science has demonstrated that vaccines do not cause autism and that the form of mercury in vaccines, unlike methylmercury, is not toxic, McDonald, feigning due diligence, cites some references from the scientific literature, including an Institute of Medicine report that the CDC also relies on to support its claims. She writes (emphasis added):
Numerous studies specifically have looked at thimerosal and autism. In 2004, the Institute of Medicine, which is now known as the Health and Medicine Division of the National Academies, reviewed the evidence and rejected a causal relationship between thimerosal-containing vaccines and autism. A 2006 study of nearly 28,000 children in Canada found pervasive developmental disorders were actually more common in the kids who received thimerosal-free vaccines — and concluded that the amount of thimerosal exposure was “unrelated” to the increasing reports of such disorders.
The CDC also published nine investigations between 2003 and 2012 that failed to find a connection between thimerosal and autism. Two of these studies observed that autism rates continued to increase in countries such as Denmark and Sweden even when thimerosal was decreased or removed from vaccines.
Finally, McDonald explains the removal of thimerosal from most childhood vaccines by writing (emphasis added):
Indeed, despite a lack of serious safety concerns, the United States decided to begin removing thimerosal from childhood vaccines in 1999, and today all vaccines for children ages 6 and younger are available without thimerosal. This, however, was not done because of concerns about autism. As the CDC explains, “This was done as part of a broader national effort to reduce all types of mercury exposure in children before studies were conducted that determined that thimerosal was not harmful. It was done as a precaution.” And consistent with the data in other countries, reported autism rates in America have continued to rise despite thimerosal removal.
So now let’s fact-check FactCheck.org’s—and by extension, the CDC’s—claims about vaccine safety.
The Safety of the CDC’s Childhood Vaccine Schedule Has NOT Been Scientifically Demonstrated
First, McDonald’s claim that numerous large studies have examined whether “any aspect of vaccination” can cause autism is a bald-faced lie.
In fact, it is such a bold lie, we can see that her claim is false by turning to her own key source from the scientific literature: the 2004 IOM report, which reviewed the available studies, including those conducted by the CDC.
It is true that the IOM report concluded that the weight of scientific evidence supported the rejection of the hypothesis that vaccines can cause autism. However, far from investigating whether “any aspect of vaccination” might increase the risk of autism, what the IOM review showed was that the studies that had been done to date had only considered one combination vaccine (the measles, mumps, and rubella, or MMR vaccine) and one vaccine ingredient (thimerosal).
Of course, concerns about the harms of vaccination are not limited to concerns only about the MMR vaccine or the use of thimerosal and whether either of those might cause autism. There are concerns about all the vaccines, both individually and cumulatively. These concerns are not limited to fears about autism, but numerous other diseases, as well, including the alarming increases in a wide range of autoimmune diseases and other developmental disorders. They are not limited to concerns about mercury, but also numerous other vaccine ingredients, including aluminum.
Today, if following the CDC’s recommended routine childhood vaccine schedule, children can be exposed to as many as 43 doses of 10 vaccines by age six—two of which are combination vaccines containing three vaccine doses each (MMR and the diphtheria, tetanus, and pertussis, or DTaP vaccine).
And, as we can learn by examining FactCheck.org’s own primary source from the literature, the studies that have been done to investigate whether there might be an association between vaccines and autism have only considered one of them.
They have only considered one vaccine ingredient, despite concerns about numerous other ingredients, including human DNA from aborted fetal tissue, animal DNA, and aluminum. There are also concerns about contamination, such as with retroviruses, which are well founded because such contamination has happened before, such as the discovery of a monkey virus in polio vaccines and pig viruses in rotavirus vaccines.
Far from numerous studies having investigated whether “any aspect of vaccination” might be associated with autism, as another report by the IOM in 2013 explicitly acknowledged, “existing research has not been designed to test the entire immunization schedule”. The IOM reiterated, “studies designed to examine the long-term effects of the cumulative number of vaccines or other aspects of the immunization schedule have not been conducted.” (Emphasis added.)
That is to say, the safety of the CDC’s routine childhood vaccine schedule has not been scientifically demonstrated. It is merely assumed. People who believe it is safe do so not based on science, but on faith.
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