Medical Institute Set to Determine if Vaccines Really Cause Autism

From the WebMD Archives

Jan. 10, 2001 (Washington) -- When Morgan S. Curtis was born, everything was normal -- at least from all appearances. He looked like any other baby, according to his parents Kenneth and Kimberly Curtis, and life was a picnic, they say. But when Morgan had just passed his second birthday, they were hit by a thunderous realization. Despite his happy demeanor and normal appearance, the couple's "pink, chubby Michelin Man" was diagnosed as being moderately autistic.

Autism: To many people, the word generates images of acclaimed Hollywood actor Dustin Hoffman in Rain Man -- a sort of idiot with sparks of genius, a savant. But the reality, Kimberly Curtis assures WebMD, is quite different. "It's hard when they can't tell you how they are or what they are thinking," she says. "It really varies from day to day."

Autism is a disorder of brain development that is characterized by problems with social interaction, communication skills, a strict routine, and the need for repetitive behavior, such as swaying or watching the same video over and over again. There is no cure, but intensive education can help autistic children develop new skills. Unfortunately, these programs are expensive and can cost anywhere from $8,000 to $100,000 a year for a residential school setting.

But for parents with newly diagnosed children, these day-to-day challenges and expenses are not the only hurdles they must overcome. Often, parents of autistic children also must deal with the simple frustration of not knowing why their child is autistic.

For that reason, Congress has now ordered the Institute of Medicine (IOM) to investigate an alleged link between childhood vaccinations and autism. The IOM is a division of the National Academy of Sciences, an institution whose members serve as scientific advisers to Congress. Meeting this Thursday, Jan. 11, the IOM is charged with the task of looking at whether childhood vaccinations really do cause autism, or if there's another cause out there that hasn't been identified.

The IOM is then required to make a recommendation on what course of action U.S. health authorities should take in terms of recommending childhood vaccinations.


For those parents of autistic children who believe there is a connection, there is a lot at stake. The current U.S. policy is to encourage timely immunizations. As a result, state authorities generally ban children from attending public schools unless they have been immunized. Some states also charge parents with child neglect and/or abuse if they fail to have their children immunized.

There is no clear evidence to establish a link between vaccination and autism. But over the past three years, the notion has gained broad support, thanks in large part to a handful of researchers. These researchers allegedly have documented a time-based association between the onset of autism and the administration of a vaccine for measles, mumps, and rubella (MMR).

The diagnosis of autism often occurs around age 2, when the MMR vaccine is administered. There also has been an apparent increase in the incidence of autism since the introduction of the MMR vaccine. These associations spurred some researchers to look for a possible link.

Chief among those is British researcher Andrew Wakefield, MD, an expert in bowel diseases at the Royal Free Hospital School of Medicine in London. In 1998, Wakefield sparked the debate by publishing a paper outlining the time-based association and hypothesizing that the MMR vaccine may trigger autism by causing bowel damage.

A damaged bowel would fail to properly filter dietary products in the gut and, in effect, allow toxic materials to be distributed in the brain, Wakefield explained.

Since then, his theory has inspired other researchers to pursue the link between MMR and autism. Among that group is Vijendra Singh, PhD, a research professor at Utah State University in Logan, Utah.

"Based upon my research, there is a good possibility that the MMR vaccine might be the culprit," Singh tells WebMD.

His research shows that up to 80% of autistic children have antibodies triggered by the measles virus that also appear to attack a particular protein in the brain, Singh explains. Therefore, it is conceivable that the MMR vaccine may be responsible because it exposes the child to the virus, Singh says. It also is not inconceivable that those children with bowel damage would be more susceptible because their brains would be exposed to a higher level of that virus, he says.


"I cannot conclusively say that I have found a fundamental cause," Singh tells WebMD. "But this is good science. It should not be ignored."

Still, the majority of experts disagree. They say the time-based association is coincidental and that autism is a genetic disease that is triggered by some other environmental factor during the first three months of pregnancy.

In fact, there is absolute proof that the MMR vaccine is not a cause of autism, says Paul Offit, MD, a pediatrician and chief of infectious disease at the University of Pennsylvania School of Medicine. The incidence of autism is really no greater whether children receive the vaccine or not, he explains. And although the diagnosis is often made around age 2, trained experts frequently can identify autistic children at a much earlier age, he tells WebMD.

As for the increase in the number of reported cases, Offit points out that U.S. and U.K. recently adopted a broader definition of autism that seems to be capturing a larger number of cases.

And as for Wakefield's bowel theory, Offit observes that Wakefield failed to study the children who got the vaccine but didn't develop autism when he developed his theory -- even though those children often exhibit the same bowel symptoms.

Despite being confident that the MMR vaccine is not a trigger for autism, Offit and his peers are concerned about the scheduled IOM review. "This is not a sound scientific process," Offit tells WebMD. "What bothers me is that this process tends to be political."

The possible connection between the MMR vaccine and autism has generated a lot of political attention. It also has managed to capture the imagination of at least one powerful Republican in Congress -- Rep. Dan Burton of Indiana, whose grandson is autistic.

Burton, who chairs the powerful House Government Reform Committee, is believed to be the root-cause behind this IOM review. In April, Burton held an emotionally charged congressional hearing, during which he explicitly stated his belief that there is a link between the MMR vaccine and autism.


Offit now fears that Burton and his supporters will use the IOM review to discourage parents from having their children immunized. "It's sad to see so much time being spent on offering parents an explanation that is so clearly wrong," Offit says.

According to the CDC, there also could be a tragic impact. Thanks in large part to the measles vaccine, the agency observes, the number of reported measles cases has now dropped to about 100 per year from more than 27,000 a year in just one decade. In 1999, the agency says, there were no reported deaths compared to about 64 deaths in 1990.

But Kimberly Curtis is not surprised at Burton's and other parents' persistence.

Anger -- That's the initial feeling parents and relatives confront when their loved ones are first diagnosed, and it feels good to have something or someone else to blame, she explains. "It's the hardest phase to deal with," she tells WebMD.

Kimberly Curtis now councils other parents with autistic children in the Washington, D.C., and Baltimore region. Since Morgan's birth about eight years ago, she has had three more children, all of whom received the MMR vaccination without becoming autistic.

The IOM committee charged with looking into the alleged connection will meet three times this year and, over the course of the next three years, also will attempt to address eight other vaccine-related safety concerns. The CDC and the National Institutes of Health, or NIH, will jointly fund the entire project.

"The intent is to have a mechanism by which we can get a [quick review and decision] by a panel of credible and nongovernment people to look at issues," Martin Myers, MD, a director of the CDC's national vaccine program, recently explained at an NIH-sponsored meeting.

The level of public concern has also made it imperative that these vaccine-related safety issues be addressed, said Kathleen Stratton, PhD, a senior IOM program director, who will help chair the 14-member review committee.