Special Court Says Connection Between Vaccines and Autism is 'Scientifically Unsupportable'

In a major blow to parents who believe that their children's autism was caused by childhood vaccines, a special court ruled today that "the theory of vaccine-related causation is scientifically unsupportable" and in three separate cases, denied parents any compensation from the makers of the vaccine.

In one of the cases, George and Victoria Mead of Portland, Oregon argued before a special master appointed by the United States Court of Federal Claims that their son William's autism was caused by mercury in the vaccine preservative thimerosal. The couple's attorney claimed that these vaccines cause brain swelling that results in autism.

Dr. Richard Besser will have more on this story tonight on "ABC World News with Diane Sawyer" on your ABC station.

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Pediatricians applauded the ruling. "The rulings support the science and clinical evidence," said Dr. Ari Brown, an Austin, Texas-based pediatrician and co-author of the book "Baby 411." "It's pretty clear it is not the cause. I hope that these rulings give additional reassurance to parents and parents-to-be about the safety of vaccines."

"Vaccinations prevent often-serious infectious diseases and have been an important reason for improved disease-free survival of children in the modern era," said Dr. Shlomo Shinnar, professor of Neurology, Pediatrics and Epidemiology and Population Health at the Albert Einstein College of Medicine in Bronx, N.Y. "While no treatment is free of side effects, they have proven safe and effective."

Dr. Michael Wasserman, a pediatrician with the Ochsner Clinic Foundation in New Orleans, La., weighed in too: "It's great to learn that evidence, logic and science are prevailing in this case."

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Parents Groups Express Outrage Over Ruling

Groups who had argued there was a link between vaccines and autism expressed outrage. One of them, the Coalition for Vaccine Safety (CVS), said in a statement that it believed the Special Masters of the Court of Federal Claims "appear to have based their decisions on the government policy to protect the vaccine program rather than to fulfill their role to do justice by vaccine-injured children."

"The deck is stacked against families in Vaccine Court," said Rebecca Estepp, a CVS steering committee member and mother of a petitioner in the Omnibus Autism Proceeding, in the statement. "Government attorneys defend a government program, using government-funded science, before government judges. Where's the justice in that?"

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"The government has its thumb on the scales of justice," said Laura Bono, parent of a child whose case was dismissed, in a statement issued by the advocacy group SafeMinds. "The process is dysfunctional and many families will not see justice done."

Autism Ruling: Court's Denial of Vaccine-Autism Link Significant

The court's rejection of the theory linking autism to vaccines is significant, particularly because the standard of proof in these vaccine cases is lower than in most court cases. The easier standard is intended to help families whose children have been injured, but even with that advantage, the science did not back up the claims.

It is not the first time that the theorized connection between autism and vaccine has been questioned by the court.

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Friday's ruling is far from the first defeat handed to the parents of approximately 5,000 children who claim that vaccines containing the mercury-based preservative thimerosal led to the development of autism spectrum disorders in their children. In a similar case before the court in February 2009, the court discounted parents' claims that the Measles-Mumps-Rubella vaccine (MMR) and thimerosal caused autism and even questioned the integrity of their medical and legal advisers. Another subsequent issue, a hypothesis that MMR vaccine alone could cause autism, was voluntarily dismissed.

Scientific Evidence Does Not Support Link

The weight of scientific evidence in recent years has overwhelmingly refuted a connection between childhood vaccines and autism. In 2001, a study showed that autism incidence has risen since thimerosal was removed from childhood vaccinations. In 2003, an Institute of Medicine (IOM) report concluded that no association exists between thimerosal and autism. And last month, the Lancet officially retracted the 1998 paper by Dr. Andrew Wakefield that served as a central pillar for the idea that vaccines and autism are somehow linked.

But despite the majority of current literature that refutes this association, including a January 2010 statement by the CDC and 2004 statement by the IOM, many parents who believe in a connection between autism and vaccines are unlikely to change their minds or accept the court's finding. Fears may still linger among parents in general as well, research shows. A survey in the journal Pediatrics on March 1 found that 90 percent of parents with minor children agreed that vaccines protected from disease, but 25 percent also indicated that they thought vaccines might cause autism.

ABC's John Donvan, Brian Hartman, and Reynolds Holding contributed to this report.