Study Shows No Link Between Autism and Measles Vaccine

A recent study found no link between the measles vaccine and autism. In the study, data on 95,000 children and their older siblings, including almost 2,000 with an older sibling with autism spectrum disorder (ASD), were examined to assess risk among those already at higher likelihood of developing autism because of a family connection. They found “no harmful association between the MMR [measles, mumps, rubella] vaccine receipt and ASD even among children already at high risk for ASD,” according to study authors, led by Anjali Jain of the Lewin Group, a healthcare consulting firm.

The study, which was funded by the National Institutes of Health and the Department of Health and Human Services, used claims data from a large commercial health plan, the Optum Research Database, part of insurer UnitedHealth. It illuminated reluctance among some parents to immunize their children if an older sibling has been diagnosed with autism. Research has shown that a child has a higher likelihood of developing autism if he or she has an older sibling with ASD. In the study, among kids whose siblings didn’t have autism, the MMR vaccination rate was 84 percent at age 2 and 92 percent at age 5. For kids with older siblings with autism, the vaccination rates were lower: 73 percent at age 2 and 86 percent at age 5. This data is particularly concerning because the vaccination rates drop below the 92 percent to 95 percent thought to be required for herd immunity.

“The only conclusion that can be drawn from the study is that there is no signal to suggest a relationship between MMR and the development of autism in children with or without a sibling who has autism,” explains Dr. Bryan King, a researcher at Seattle Children’s Autism Center and the University of Washington. “Taken together, some dozen studies have now shown that the age of onset of ASD does not differ between vaccinated and unvaccinated children, the severity of course of ASD does not differ between vaccinated and unvaccinated children, and now the risk of ASD recurrence in families does not differ between vaccinated and unvaccinated children.”

The study was published April 21 in The Journal of the American Medical Association.