No, the autism “rate” in California did not go down after removing thimerosal from vaccines

26 Feb

I recently attended a talk where the speaker showed autism prevalence by age group for a large HMO in California. The administrative prevalence (fraction of people in the HMO identified autistic) was still going up as of 2010, and the speaker indicated this trend continued to 2012. California is an interesting case study because not only was thimerosal removed from vaccines along with the rest of the U.S. starting in the late 1990’s, but the state enacted a law which required that pregnant women and children under three be given thimerosal free vaccines from 2006 onward. So, with the exception of an an exemption in 2009 and another one right now, even the influenza vaccine in thimerosal free. I bring this up because it is a common argument that somehow the exposure from the flu vaccine is keeping the rate climbing, even though at most this is a lower exposure than that from the 1990’s pediatric vaccine schedule.

This all said, the talk made me dive back into looking at autism prevalence. I decided to finally write about the fact that the autism prevalence in Denmark is higher post thimerosal than while thimerosal containing vaccines were in use. This is completely unsurprising, but a myth has been propogating that it came down and that fact was being hidden.

As it turns out I also checked back with what once was the most common source of autism data for the armchair epidemiologist: the California Department of Developmental Services (CDDS). (I admit one could argue that Special Education data are the most common source for the armchair epidemiologist). The CDDS provides services to disabled Californians and keeps and makes public statistics on their client base. For a long time, every quarter they would come out with a report. For a long time, every quarter these reports would be followed by announcements about how the data showed that vaccines cause autism. One of the people you could always count on was David Kirby (author of the book, Evidence of Harm: Mercury in Vaccines and the Autism Epidemic: A Medical Controversy, and basically a PR man for some of the vaccine-causation groups). Mr. Kirby went so far as to claim that these data were the “gold standard of autism epidemiology”. Well, the data had their uses (such as identifying and quantifying some of the social influences behind the increase) but it is not an easy task to get results from them. The idea that they represent an accurate count of all those with ASD’s (or even accurately account for all individuals with autistic disorder) is a stretch.

But this didn’t stop David Kirby. Back in 2005, David Kirby was claiming that there was an indication that the administrative prevalence in California was starting to drop, and if the trend continued this was a sign that the removal of thimerosal was having an effect:

Stay tuned. If the numbers in California and elsewhere continue to drop – and that still is a big if — the implication of thimerosal in the autism epidemic will be practically undeniable.

Well, by 2007 it was clear that the California data were not really showing a drop. In addition, the lack of a drop was published in 2008 as Continuing increases in autism reported to California’s developmental services system: mercury in retrograde.\

The rise in the number of autism clients in the CDDS database was key to the idea of the mercury-induced epidemic. David Kirby (and others) relied on these data and Mr. Kirby even acknowledged that the data should start showing a drop (statement from 2005):

If the total number of 3-5 year olds in the California DDS system has not declined by 2007, that would deal a severe blow to the autism-thimerosal hypothesis.

The reason is that 5 year olds in 2007 were born after the removal of thimerosal from vaccines. Their exposure to thimerosal was much less than kids in the 1990’s. If the “thimerosal caused an autism epidemic” idea were true, the rates would have to drop. They should drop back to pre-1990 (actually pre 1980) levels if thimerosal were the main, or even a main, cause of the rise.

My recollection is that Mr. Kirby did later backpedal and claim that we would have to wait until some much later date, but it was a weak argument (even by David Kirby standards).

Sorry to keep diving into past history, but one of the strangest moments in the mecury debate (and I can use the term this time, because there was a debate) came in San Diego in 2007. David Kirby debated Arthur Allen in the UCSD Price Center (about 100 yards from my old office, as it turns out). Presented with the fact that even though thimerosal exposure from vaccines had gone down, the California numbers kept going up, David Kirby presented (in something like 100 power point slides!) a four pronged response. First was a claim that California HMO’s had stockpiled thimerosal containing vaccines, so the exposure from vaccines didn’t really go down as much as reports were claiming. Then:

1) A gigantic plume of coal smoke from Chinese power plants has settled on California, depositing lots of mercury and therefore causing the autism numbers in the state to continue to grow.

2) Bad forest fires have put tons of mercury into the air, depositing lots of mercury etc…

3) Cremations (!). The burning of dead bodies with mercury amalgam in their mouths has added even more mercury to the air.

It was a hail Mary pass, to be blunt. Lot’s of handwaving and ignoring the facts.

In 2007, the CDDS changed the way they assessed and counted their clients and they stopped publishing the quarterly reports. As you can imagine, many claimed this was part of a conspiracy to hide the fact that the autism rates were declining in California. And with that the quarterly ritual of misinterpreting and deconstrucing the data came to an end.

All amusing history, sure, but one might ask, why bring all this up again? Well, because it turns out that the CDDS started putting out quarterly reports again in 2011. Yes, there’s a gap of a few years in the data. Yes, some things changed (for example, the CDDS now shows the PDD fraction of autism client base). Given these limitations–and the other limitations in the CDDS data (i.e. they are *not* the “gold standard” of autism epidemiology), what do these data show? The upward trends continue. More individuals served by the CDDS with autism, even though thimerosal was removed from vaccines. Here’s the total–all ages–count for CDDS clients in the autism category (click to enlarge):

CDDS total

Looking at the younger age groups, those whose exposure to thimerosal is much lower than for kids born in the 1990s, there is also an increase. Here is the age 3-5 age group (click to enlarge)

CDDS 3-5

and the 6-9 age group (click to enlarge):

CDDS 6-9

9 year olds in 2012 were born in 2003. Post the removal of thimerosal nationwide. 5 year olds were born in 2007, post thimerosal nationwide and post the California law prohibiting mercury in vaccines for pregnant women and small children. In both groups, the CDDS autism counts are higher than they were in 2002 (the earliest date in the currently available data). Which, in turn, was much higher than the counts from the 1990’s. Here is a figure from the Schechter-Grether paper refenced above:

S-G CDDS paper figure

Which is all a very long way of saying: years ago the evidence was against the thimerosal/epidemic idea; it is even more clear now. For years we heard Mr. Kirby and others talk about how those responsible should step up and admit what happened. Well, the fact is they did. Now it is time for those who promoted the mercury notion to step forward and show they have the guts to admit they were wrong. Because they were. Clearly wrong. It would take a lot of guts to step forward and admit the mistakes. Even though their influence has waned, it would help the autism communities. While I have focused on David Kirby in this discussion, the list is much longer of people who should step forward. I’m not going to hold my breath.

By Matt Carey

25 Responses to “No, the autism “rate” in California did not go down after removing thimerosal from vaccines”

  1. Grant February 26, 2013 at 16:30 #

    Sully, did you correct your numbers for better diagnosing and change of criteria? Isn’t this what you claim is behind the increase in autism numbers? Also, isn’t Schechter the director of immunization in California? To show that autism isn’t linked to the injection of infants with organic mercury which he supports, can we really trust his statistical analysis for this subject? Why is the director of immunization in California doing autism epidemiology work anyway? Doesn’t the position of director of immunization keep him busy enough?

    • Lara Lohne February 26, 2013 at 20:20 #

      When has any infant been injected with organic mercury? Thimerosal is a compound that contains mercury atoms, but is not by any stretch organic mercury. I feel it is actually in Schechter’s interest to show that vaccinations have no link to autism and the increase that we have seen is clearly due to better awareness and more broad diagnostic criteria. If one looks back on when the numbers began to rise, it coincides with the changes to the diagnostic definitions in 1994. This fact always seems to be ignored by vaccine causation propagators. I predict once the DSMV criteria are used, we will see another shift in prevalence, could go up, could go down. We definitely won’t see a rise in Asperger’s diagnosis simply because that is being done away with as a separate from ASD diagnosis. But we probably will see an increase in the cases of Language Disorder.

      • Grant February 26, 2013 at 20:37 #

        Thimerosal rapidly converts to ethylmercury in the body. Ethylmercury is a short chain aklymercury compound, just one carbon group removed from methylmercury. Organic mercury is just another term for alkylmercury compounds. Not much of a stretch at all Lara.

      • Sullivan (Matt Carey) February 26, 2013 at 23:43 #

        Thimerosal doesn’t increase autism risk. Multiple studies show this.

        The rise in autism diagnoses was not due to thimerosal. Same data that was used to claim there was a vaccine “epidemic” now shows that it wasn’t the cause.

        Glad you got to learn a little chemistry in the meantime, but it is irrelevant.

      • novalox February 27, 2013 at 02:01 #


        Do you even know the difference between ethylmercury and methylmercury?

        Also, have you ever heard of the phrase “The dose is the poison?”

    • Lawrence February 26, 2013 at 21:20 #

      @Grant – and table salt is made up of Chlorine and Sodium, both of which are toxic in their pure forms……chemistry at work.

    • Sullivan (Matt Carey) February 26, 2013 at 23:55 #

      He was chief of the technical assistance section, not of the entire immunization branch, at least as of 2009 (announcement below). But I agree that he had better things to do than show, yet again, that the increase in autism diagnoses was not due to thimerosal.

      Unfortunately there was enough misinformation about that he had to do this.

      So, if you want me to say “people promoting the notion that thimerosal was behind the increases in autism diagnoses forced public servants to take time away from other duties” I’ll agree. Somehow I don’t think that’s your point. It is the most clear point.

      Beginning February 17, Dr. Robert Schechter, Chief of the Branch’s Technical Assistance Section, will serve as Interim Immunization Branch Chief.  Dr. Backer is expected to return to his position as Branch Chief later this year

    • Sullivan (Matt Carey) February 27, 2013 at 00:06 #

      I love to see the conversations reversed. “Did you correct for changes…”

      No. I didn’t include the effects of diagnostic substitution, diagnostic accretion or other effects that made big changes…partly because those results were from the data from the 1980’s through early 2000’s.

  2. lilady February 26, 2013 at 21:53 #

    Here’s the AAP Statement in support of the WHO’s continued use of multi-dose vials of vaccine:

    “….Although there are clear neurotoxic effects of methyl mercury absorption, ethyl mercury has not been associated with those consequences. Nevertheless, before data were available on risks of thimerosal in vaccines, in 1999 the American Academy of Pediatrics and the US Public Health Service recommended moving toward removing thimerosal use in preservatives as a precautionary measure.3 Thus, thimerosal as a preservative has been removed from most vaccines in the United States, generally resulting in distribution of vaccines in single-dose rather than multidose vials. US vaccines routinely recommended for children that still contain thimerosal as a preservative are seasonal influenza vaccines including the multi-dose presentation Afluria (CSL Limited) and multidose formulations (Fluzone (Sanofi Pasteur) and Fluvirin (Novartis).4 Thimerosal remains an important vaccine preservative in resource-poor countries. Thimerosal allows the use of multiuse vials, which reduce vaccine cost and the demand on already constrained cold-chain systems. Even in the United States, thimerosal could be critical for dealing with emergencies and the need to rapidly increase vaccine supply and delivery, such as during a serious pandemic of influenza.5…”

    Here’s the “show-stopper” for people who still don’t understand the differences between ethyl mercury compounds (Thimerosal), elemental Hg and methyl mercury.

    “Overwhelmingly, the evidence collected over the past 15 years has failed to yield any evidence of significant harm, including serious neurodevelopmental disorders, from use of thimerosal in vaccines. Dozens of studies from countries around the world have supported the safety of thimerosal-containing vaccines. Specifically, the Institute of Medicine, and others have concluded that the evidence favors rejection of a link between thimerosal and autism.6–12 Careful studies of the risk of other serious neurodevelopmental disorders have failed to support a causal link with thimerosal.13–17 In May 2002, the American Academy of Pediatrics retired its 1999 statement on thimerosal after evaluating new studies.3,18 The original decision is explained in an accompanying commentary in this issue by Dr Louis Z. Cooper and Dr Samuel Katz.19 Had the evidence that is available now been available in 1999, the policy reducing thimerosal use would likely have not been implemented. Furthermore, in 2008 the World Health Organization (WHO) endorsed the use of thimerosal in vaccines.20”

    @ Matt Carey: I’ve already *bookmarked* this article in a special folder…I am soooo going to use it when I respond to crank bloggers and their groupies who think of David Kirby as a reliable source on vaccines.

  3. Senrion Alanlyst February 27, 2013 at 09:23 #

    It’s a myth thimerasol has been removed from vaccines. It has not. Go ask if your flu vac is mercury free. It isn’t. only a few are and you have to special order them and then they still have other toxins. You can’t make a vaccine without toxins. Right now it’s not even remotely possible.

    • Sullivan (Matt Carey) February 27, 2013 at 13:30 #

      My last flu vaccine was mercury free. My doctor is also a pediatrician and he seems to only stock mercury free vaccines. The law in California is that pregnant women and children three and under can only be given mercury free vaccines, so he probably keeps mercury free entirely for convenience.

      I don’t think it’s that rare to get mercury free flu vaccines given that law is in place.

      Ask this question: what was the exposure to thimerosaal in the 1980’s, 1990’s and now?

      My recollection is:

      In the 1980’s, infants received 75 micrograms in vaccines. 3 DTP shots.

      In the 1990’s the oft quoted value was something like 187.5 micrograms.

      Now, there can’t be more than 1microgram per shot. In a lecture Laura Hewitson of Thoughtful House gave about her monkey study, she said that they measured much lower than 1 microgram.

      Assume the highest value, 1 microgram per shot. Kids today would get a maximum of about 20 micrograms exposure. Less than 1/3 the expo are in the 1980’s.

      Ask yourself, why haven’t autism rates fallen to pre 1980 reported levels?

      If you want to say “it’s aluminum” then ask, how much did aluminum exposures change in the past decade?

      The thimerosal epidemic didn’t happen.

    • Chris February 27, 2013 at 22:30 #

      According to this page out of a total of 145 million doses of flu vaccine, about 62 million will be thimerosal free.

      I do not consider over 40% to be a “few.” You may have another definition.

      And, as far as those other “toxins”, what you need to do is provide actual evidence that a vaccine is more toxic than the actual disease. I am waiting for someone to actually give me the proper analysis showing us that DTaP is more toxic than the toxins created by each of the bacteria that cause diphtheria, tetanus and pertussis. And, yes, the main damage of those diseases is caused by those very real toxins.

      • Sullivan (Matt Carey) February 28, 2013 at 00:11 #

        I don’t consider 62 million a few, either. Otherwise, I would like a few dollars, please 😉

      • Lara Lohne February 28, 2013 at 00:56 #

        Nice one Matt! LOL! Should you find that ‘few’ dollars, could I borrow a few of them?

    • brian February 28, 2013 at 21:41 #

      You might want to try to understand that the definition of “toxin” is not “something I don’t like or something that I can’t pronounce.”

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