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Autism Risk Unrelated to Total Vaccine Exposure in Early Childhood

Science Update

A child’s risk for developing an autism spectrum disorder (ASD) is not increased by receiving “too many vaccines too soon,” according to a new study published in The Journal of Pediatrics .

Although previous scientific evidence has shown that vaccines do not cause autism, more than 1 in 10 parents refuse or delay vaccinations for their young children. A main safety concern of these parents is the number of vaccines administered, both on a single day and over the course of a child’s first 2 years of life.

In the first study of its kind, researchers from the CDC and Abt Associates, Inc. compared vaccine records for over 1000 children born from 1994–1999, some of whom were later diagnosed with ASD. The researchers calculated the total number of vaccine antigens each child received between birth and age 2, as well as the maximum number of antigens each child received on a single day.

The study found that the total number of vaccine antigens received was the same between children with ASD and those without ASD. Additionally, antigen number was also found to be unrelated to the development of two sub-categories of ASD—autistic disorder and ASD with regression.

The researchers concluded, “The possibility that immunological stimulation from vaccines during the first 1 or 2 years of life could be related to the development of ASD is not well-supported by what is known about the neurobiology of ASDs.”

Learn more about autism spectrum disorders.