Researchers discovered no link between the measles vaccine and increased risk of autism, a common concern cited by anti-vaccination advocates.
A study published Tuesday in the Journal of the American Medical Association reports that a sampling from nearly 100,000 children produced no evidence that the vaccine against the once-common ailment increases the risk of autism in children.
A late 2014 measles outbreak at Disneyland in California was linked to unvaccinated children. The issue highlighted the anti-vax movement, which is composed of parents who decline to vaccinate their children due to concerns about adverse health reactions.
Among other highly publicized claims, anti-vaxxers posit a link between the measles-mumps-rubella (MMR) vaccine and increased diagnoses of autism. The measles vaccine was introduced in 1963, and the Centers for Disease Control reports an increase in autism prevalence from 6.7 children in every 1,000 in 2000 to 14.7 in every 1,000 in 2010.
For the new report, researchers looked at a sample of insurance claims for 95,000 privately insured children who had older siblings from January 1997-December 2012. The children were continuously enrolled in a private health plan from birth to at least five years of age.
Of the children, 1,929 had an older sibling with autism and were therefore at a higher risk for autism.
The vaccination rate for children with siblings without autism was 84 percent at two years and 92 percent at age five years, said the
The vaccination rates for children with older siblings who had autism were lower, 73 percent at two years and 86 percent at five years.
Researchers found no association between vaccination and increased autism risk. They also found no link between either one or two doses of the vaccine and autism. The measles vaccine is recommended for children ages 12-15 months and a second dose for ages four-six years old.
The study also noted that the data come from children enrolled in a private health plan for five years and might not apply to other groups.
“The findings of this study may not be applicable to more ethnically and socioeconomically diverse populations that have less access to health care services,” the authors of the study note.
Anti-vaccination advocates frequently point to a 1998 study from a group led by Andrew Wakefield. The study has been widely debunked and was retracted by the medical journal that published it.
However, concerns sparked by that study persist.
The anti-vaccination site ThinkTwice Global Vaccine Institute did not immediately return a request for comment.
