(CN) - Parents with autistic children failed to prove that the vaccination for measles, mumps and rubella caused their children's neurological disorders, three special masters of the U.S. Court of Federal Claims ruled Thursday.
The court issued three rulings on test cases of the more than 5,000 claims filed through the government's Vaccine Injury Compensation Program. Parents blamed the MMR vaccine and a mercury-containing preservative called thimerosal for causing autism or autism-like symptoms in their children.
Special Master Hastings, a judge in one of the cases, said the evidence was "overwhelmingly contrary" to the parents' claims.
"The expert witnesses presented by (the government) were far better qualified, far more experienced, and far more persuasive than the petitioners' experts, concerning most of the key points," Hastings wrote. "The numerous medical studies concerning these issues, performed by medical scientists worldwide, have come down strongly against the petitioners' contentions."
Special Master Vowell came to the same conclusion, noting, "It was abundantly clear that petitioners' theories of causation were speculative and unpersuasive."
Families of autistic children failed to meet their burden of proof that their children's symptoms were probably directly linked to a combination of MMR shots and other shots containing thimerosal, the judges ruled.
The court has yet to rule on separate claims that thimerosal alone caused autism symptoms, but the rulings on Thursday signaled skepticism.
"The petitioners have failed to demonstrate that thimerosal-containing vaccines can contribute to causing immune dysfunction," Hastings wrote.
The three rulings are Cedillo v. Secretary of Health and Human Services, decided by Hastings; Hazlehurst v. Secretary of Health and Human Services, issued by Special Master Campbell-Smith; and Snyder v. Secretary of Health and Human Services, written by Vowell.
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