Article

Immunizations and autism: A review of the literature

Division of Neurology, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada.
The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques (Impact Factor: 1.6). 12/2006; 33(4):341-6.
Source: PubMed

ABSTRACT Because of a temporal correlation between the first notable signs and symptoms of autism and the routine childhood vaccination schedule, many parents have become increasingly concerned regarding the possible etiologic role vaccines may play in the development of autism. In particular, some have suggested an association between the Measles-Mumps-Rubella vaccine and autism. Our literature review found very few studies supporting this theory, with the overwhelming majority showing no causal association between the Measles-Mumps-Rubella vaccine and autism. The vaccine preservative thimerosal has alternatively been hypothesized to have a possible causal role in autism. Again, no convincing evidence was found to support this claim, nor for the use of chelation therapy in autism. With decreasing uptake of immunizations in children and the inevitable occurrence of measles outbreaks, it is important that clinicians be aware of the literature concerning vaccinations and autism so that they may have informed discussions with parents and caregivers.

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    • "However, the evidence for these risk factors, such as gastrointestinal or immune system abnormalities, allergies, and exposure of children to drugs, infection, certain foods, or heavy metals needs further substantiation. Vaccination can no longer be regarded as risk factor for autism (Doja and Roberts, 2006). Evidence from several rigorous scientific studies examining an association between vaccine use and autism have not identified such a link (Miller and Reynolds, 2009) and the data of former studies claiming an association were shown to be scientifically fraudulent (Flaherty, 2011). "
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    • "Because those data pertain primarily to children, and cognitive outcomes of Hg toxicity may vary with developmental stage at exposure, effects of thimerosal are beyond the scope of this paper. Detailed reviews are available elsewhere (Clements & McIntyre, 2006; Doja & Roberts, 2006; Nelson & Bauman, 2003). "
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