The idea that vaccines are a primary cause of autism has been around for some time. The idea took off in the 1990’s when Andrew Wakefield claimed that the MMR was causing autism, including suggesting that not only was MMR causing autism but was responsible for the rise in diagnoses observed. Later, the idea that the increase in thimerosal exposure in the pediatric vaccine schedule of the 1990’s in the US was proposed by some groups as causing the increase in diagnoses. Both ideas have since been shown to be invalid. As the evidence mounted that the idea that thimerosal and/or MMR caused an autism epidemic was false, the idea that the increase in vaccines themselves was causing autism. This idea was popularized by Jenny McCarthy of Generation Rescue in the slogan “too many too soon”.
The study is in the journal Pediatrics (full version available free): Increasing Exposure to Antibody-Stimulating Proteins and Polysaccharides
in Vaccines Is Not Associated with Risk of Autism.
The abstract:
Objective To evaluate the association between autism and the level of immunologic stimulation received from vaccines administered during the first 2 years of life.
Study design We analyzed data from a case-control study conducted in 3 managed care organizations (MCOs) of 256 children with autism spectrum disorder (ASD) and 752 control children matched on birth year, sex, and MCO. In addition to the broader category of ASD, we also evaluated autistic disorder and ASD with regression. ASD diagnoses were validated through standardized in-person evaluations. Exposure to total antibody-stimulating proteins and polysaccharides from vaccines was determined by summing the antigen content of each vaccine received, as obtained from immunization registries and medical records. Potential confounding factors were ascertained from parent interviews and medical charts. Conditional logistic regression was used to assess associations between ASD outcomes and exposure to antigens in selected time periods.
Results The aOR (95% CI) of ASD associated with each 25-unit increase in total antigen exposure was 0.999 (0.994-1.003) for cumulative exposure to age 3 months, 0.999 (0.997-1.001) for cumulative exposure to age 7 months, and 0.999 (0.998-1.001) for cumulative exposure to age 2 years. Similarly, no increased risk was found for autistic disorder or ASD with regression.
Conclusion In this study of MCO members, increasing exposure to antibody-stimulating proteins and polysaccharides
in vaccines during the first 2 years of life was not related to the risk of developing an ASD.
The study included autism with regression.
Of the 321 potential case children who participated in standardized assessments, 256 (79.8%) met study criteria for ASD. Among these 256 children, 187 (73%) met the stricter criteria for AD and 49 (19%) met the criteria for ASD with regression.
The authors begin the discussion section with:
We found no evidence indicating an association between exposure to antibody-stimulating proteins and polysaccharides contained in vaccines during the first 2 years of life and the risk of acquiring ASD, AD, or ASD with regression. We also detected no associations when exposures were evaluated as cumulative exposure from birth to 3 months, from birth to 7 months, or from birth to 2 years, or as maximum exposure on a single day during those 3 time periods. These results indicate that parental concerns that their children are receiving too many vaccines in the first 2 years of life or too many vaccines at a single doctor visit are not supported in terms of an increased risk of autism.
Are there limitations to this study? Sure. Enough to discount it or disregard it? No. Will some people discount it and disregard it? Yes.
Thimerosal doesn’t increase autism risk. MMR doesn’t increase autism risk. Number of antigens in vaccines doesn’t increase autism risk. There is limited researcher time and money in this world. It is good that we are applying those resources to other areas of autism etiology.
The CDC discusses this at Vaccines not associated with risk of autism. Shot of Prevention discusses this in Study Concludes Concern Over “Too Many, Too Soon” is Unfounded.
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By Matt Carey
Left Brain Right Brain 
Great post and great analysis of this latest study.
I agree with you…it is high time that we move past investigating the thoroughly debunked *theories* that vaccines, the ingredients in vaccines, the timing of vaccines and the number of antigens contained in vaccines are associated with the onset of ASDs.
Regardless of whether Thimerosol is linked to autism, it’s still 49% mercury. Thats reason enough to avoid vaccines that contain it.
@Krissy – please inform us as to what Pediatric Vaccines still contain Thimersol? That is so 1999 – this is 2013, a lot has changed since then.
Please tell us which vaccine on the present American pediatric schedule is only available with thimerosal. Please do not included influenza since half are thimerosal free.
I agree with you. That’s why I don’t eat any salt. Salt is 50% chloride, which makes chlorine gas. Chlorine gas is a weapon of mass destruction, a chemical weapon. Totally with you on this. There is no difference between mercury and thimerosal… Oh, wait. Nevermind. I took basic chemistry. It’s not.
Seawater and sea salt contain Uranium.
Drink Brawndo instead!
@krissy
Also, have you ever heard “the dose is the poison?”
Krissy has put her fingers in her ears and is loudly saying la la la la la.
It is tragic how many people still are fixated on this vaccine issue. But unfortunately a typical response when we are confronted by poignant problem with basically unknown causes.