IMFAR study: No Differences in Early Immunization Rates Among Children with Typical Development and Autism Spectrum Disorders

3 May

IMFAR, the International Meeting For Autism Research, is going on this week.  In preparation for the meeting, I posted the titles of a number of studies being presented.  The full abstracts are now available.  One might venture to guess that for a segment of the online parent community, this study (sadly) may get the most attention: No Differences in Early Immunization Rates Among Children with Typical Development and Autism Spectrum Disorders

It is not one of the very large population based epidemiological studies which have many thousands of participants.  But it is a good sized study with confirmed diagnoses.

As the abstract states, the difference immunization rates is not significant, with the autistic kids rate reported as slightly lower. One child was unimmunized, and that child is autistic.

One vaccine with significantly different uptake rates is the Hepatitis B vaccine, with autistic kids receiving this at a lower rate than the typically developing kids.  The HepB vaccine is one that gets a great deal of focus by those claiming vaccines causes an autism epidemic, with claims of much higher autism risk among those vaccinated with HepB. If this were true, one would expect the autistic group to show a higher uptake of this vaccine.

All in all, as the authors note, this is not a study about causation but the results do not lend support to the idea that vaccines are associated with higher autism risk. The study was undertaken by the MIND Institute, which is generally respected by the groups who promote the idea that vaccines are associated with autism.

K. Angkustsiri1,2, D. D. Li3 and R. Hansen2,4, (1)UC Davis MIND Institute, Sacramento, CA, (2)UC Davis Medical Center, Sacramento, CA, (3)M.I.N.D. Institute and Department of Psychiatry and Behavioral Sciences, University of California Davis Medical Center, Sacramento, CA, (4)The M.I.N.D. Institute, University of California, Davis, Sacramento, CA

Background: The relationship between vaccines and autism spectrum disorders (ASD) has been of great interest to families and health providers.

Objectives: This study compares the immunization practices of preschoolers with ASD and typical development (TD).

Methods: Immunization records were abstracted from 240 (161 ASD, 79 TD) children between the ages of 24.1-54.4 months participating in the Autism Phenome Project from April 2006 to August 2011. Seventy-eight percent were male. We compared immunization rates for the vaccines required by the State of California for children ages 18 months to 5 years (3 doses of Hep B, 4 DTAP, 4 Hib, 4 PCV, 3 IPV, and 1 MMR). Of note, there was a national HIB vaccine shortage from 2007-2009. Varicella was not included due to the possibility of naturally acquired immunity. 

Results: Immunization rates in ASD children were slightly lower than in TD (see Table 1), but this difference was not statistically significant, with the exception of Hep B, where 91.3% of children with ASD had received 3 doses compared to 98.7% of TD (p=0.024). These rates were at or above those reported in the 2011 National Immunization Survey (NIS). One (0.6%) ASD child had not received any immunizations. The national rate for children who received no immunizations was 0.8%. 

Conclusions: Despite the lack of evidence supporting any causal relation of vaccines to ASD (IOM, 2011) many parents remain concerned and some choose to delay or avoid vaccines. Immunization rates in preschoolers with ASD in our sample were generally lower than TD, although there were no statistically significant differences except for Hep B.  Our study, although not designed to specifically address a causal relationship, does not support an association between vaccines and ASD. In most cases, these immunization practices represent behavior during the first 18 months of life prior to receiving an ASD diagnosis. Further study looking at differences in vaccine acceptance during the 4-6 year booster period is warranted, as having an ASD diagnosis may affect parents’ attitudes towards future immunization.

ASD (n=161) TD (n=79) p-value 2011 NIS
Hep B 147 (91.3%) 78 (98.7%) 0.024 91.1%
DTAP 150 (93.2%) 78 (98.7%) 0.110 84.6%
Hib 107 (66.5%) 48 (60.8%) 0.386 shortage 2007-09
PCV 134 (83.2%) 66 (83.5%) 0.128 84.4%
IPV 149 (92.5%) 78 (98.7%) 0.066 93.9%
MMR 151 (93.8%) 75 (94.9%) 0.99 91.6%

By Matt Carey

13 Responses to “IMFAR study: No Differences in Early Immunization Rates Among Children with Typical Development and Autism Spectrum Disorders”

  1. futuredave5 May 3, 2013 at 21:24 #

    So did you happen to see any studies about whether autistic children tend to have more severe vaccine reactions? Or are all the studies just re-hashing old questions?

    • Chris May 4, 2013 at 02:13 #

      If they have more severe reactions to vaccines, would they not also have a much more severe reaction to the actual disease? It does not seem logical that a child would fare better with the disease versus that of a vaccine.

      • Dave May 5, 2013 at 01:41 #

        Chris, That seems like a good question as well. If only there were some sort of organization that met to study such questions.

        I don’t know that my son has ever had any diseases that were as serious as his vaccine reactions. But that might be because we got the vaccines anyway.

      • Chris May 5, 2013 at 02:17 #

        My now adult son had one that caused seizures before its vaccine was available. I met a woman whose first child died from meningitis from Hib (the disease, the vaccine was not yet out). There were kids in the deaf/hard of hearing preschool next to my son’s special ed. program that had measles or mumps before coming to the USA.

        There is a reason that there is an effort to prevent certain diseases, they do cause real damage.

  2. Jort May 4, 2013 at 00:29 #

    So another study that says not all vaccinated children develop autism. Don’t we already know that?

  3. krissy May 4, 2013 at 01:13 #

    That measles outbreak in Wales is pretty horrible.

  4. lauren May 6, 2013 at 14:37 #

    I really dont understand why people freak out so much about autism? I have autism. I’m an adult now and yes growing up was a little tuff but it is with most children and everything I’ve gone through has just made me that little bit wiser. I love my life and I wouldn’t change anything about my life or who I am. I have a talent for working with children and animals that most people take years to learn how to do or never learn how to do. My older brother has a more severe type of autism and he’ll never be able to live by himself but he also loves his life and wouldn’t change it. This whole vaccine thing, to me, just sounds like parent’s not excepting their children for who they are and see difference in people as a negative thing and that they would rather see their child dead from measles, mumps, etc. than have a child with ‘god forbid’ AUTISM!
    Seriously, get over yourself, we aren’t effing mongaloids!

    • Lawrence May 6, 2013 at 14:45 #

      @Lauren – be careful with how you portray others. Kids with Downs have as much right to live their lives as they wish as you do. That language is downright offensive.

    • Sullivan (Matt Carey) May 6, 2013 at 14:58 #


      I would encourage you to reconsider your statement. “Effing Mongoloids” is a very derogatory way to refer to people with Down syndrome. Even without the term, there’s no value in the comparison between disabilities.

      That said, many parents of children with Down syndrome provide a good example of avoiding stigmatizing portrayals of their children. Yes, it’s a very sadly self-selective group

  5. Eric B Baum PhD January 19, 2014 at 22:36 #

    As I read the study above, it says that the kids with autism had just about as many vaccines as the kids without autism. All this seems to imply is that the parents of autistic kids continued vaccinating them for the most part after they got autism, but maybe some of them stopped. It doesn’t actually even say that there was a single case of autism in their database who’d never gotten a vaccine.

    • Sullivan (Matt Carey) January 19, 2014 at 23:15 #

      No. But the authors did. Email. It’s a wonderful thing.


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    […] the “vaccine wars,” even when, yet again, we find that there is no link between autism and vaccines (any vaccine), I sometimes come across stories that shake me to the core. This is one such story, […]

  2. The measles situation in Wales, autism in the nonvaxxed, and flu jabs | autismjungle - May 5, 2013

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