Do vaccinations increase the risk of Autism Spectrum Disorder (ASD)?

From the Guidelines

Vaccinations do not increase the risk of Autism Spectrum Disorder (ASD). This is supported by a large body of scientific evidence, including a statement from the American Academy of Pediatrics (AAP) that "thimerosal-containing vaccines are not associated with increased risk of autism spectrum disorders in children" 1. The AAP extends its strongest support to the current World Health Organization recommendations to retain the use of thimerosal as a preservative in multiuse vials in the global vaccine supply. The benefits of protecting children against the known risks of influenza are clear, and children should receive any available formulation of an inactivated influenza vaccine (IIV) rather than delaying vaccination while waiting for reduced thimerosal-content or thimerosal-free vaccines 1.

Some key points to consider:

• A large body of scientific evidence demonstrates that thimerosal-containing vaccines are not associated with increased risk of autism spectrum disorders in children 1.
• Thimerosal from vaccines has not been linked to any medical condition, including autism spectrum disorder 1.
• The American Academy of Pediatrics (AAP) supports the current World Health Organization recommendations for use of thimerosal as a preservative in multiuse vials in the global vaccine supply 1.
• The benefits of protecting children against the known risks of influenza are clear, and children should receive any available formulation of an IIV rather than delaying vaccination while waiting for reduced thimerosal-content or thimerosal-free vaccines 1.

It is essential to note that the concern about a link between vaccines and autism originally stemmed from a now-discredited 1998 study that suggested a link between the MMR (measles, mumps, rubella) vaccine and autism. This study was later found to be fraudulent and was retracted. Since then, extensive research involving millions of children has consistently shown no link between vaccines and autism. Autism is a complex developmental disorder that begins before birth, long before a child receives any vaccines. The apparent "onset" of autism often coincides with the age at which children receive many of their vaccinations, which has led some to incorrectly assume a causal relationship. Vaccines are rigorously tested for safety and are continuously monitored. They prevent serious diseases and save millions of lives. Parents should follow the recommended vaccination schedule provided by their healthcare provider to protect their children's health.

From the Research

Vaccinations and Autism Spectrum Disorder (ASD)

• There is no evidence to suggest that vaccinations increase the risk of Autism Spectrum Disorder (ASD) 2, 3, 4, 5, 6
• Multiple studies have investigated the potential link between vaccinations and ASD, including the measles, mumps, and rubella (MMR) vaccine and preservatives used in other childhood vaccines, and found no association 2, 3, 6
• A meta-analysis of case-control and cohort studies found no relationship between vaccination and autism or ASD, and no relationship between autism and MMR, thimerosal, or mercury 2
• A nationwide cohort study in Denmark found no increased risk for autism after MMR vaccination, and no evidence for increased risk of developing autism or ASD following MMR, mercury, or thimerosal exposure 3
• The majority of scientists, physicians, and public health researchers refute causation between vaccines and autism, and the presumed association has been a major contributor to parents' refusal to immunize their children 4

Study Findings

• A study published in 2014 found that the components of vaccines (thimerosal or mercury) or multiple vaccines (MMR) are not associated with the development of autism or ASD 2
• A study published in 2019 found that MMR vaccination does not increase the risk for autism, and is not associated with clustering of autism cases after vaccination 3
• A study published in 2022 found that despite the overwhelming data demonstrating that there is no link between vaccines and autism, many parents are hesitant to immunize their children because of the alleged association 4
• A systematic review published in 2022 explored the link between vaccination and autism in children, and found no evidence to support a link between the two 5
• A study published in 2010 found that the etiology of autism is still unknown, but extensive research indicates that childhood vaccination is not a cause of the sharp increase in autism diagnoses in recent decades 6