April 25, 2001 (Washington) -- A report that virtually cleared the measles-mumps-rubella vaccine as a possible cause of autism came under withering attack on Capitol Hill Wednesday, with legislators questioning the document's accuracy and integrity. Chairman Dan Burton (R-Ind.) of the House Committee on Government Reform said the analysis was a "disservice to the American people."
The study, which was published Monday, said that the universally used preventive shot apparently doesn't cause the incurable brain disorder.
Still, the panel of experts assembled by the National Academy of Sciences' Institute of Medicine (IOM) couldn't completely rule out the link between the disease and the vaccine in a small number of children. The ambiguity of the findings infuriated Burton, who is holding two days of hearings this week on the skyrocketing rate of autism in the United States.
"You put out a report to the people of this country, saying the [MMR vaccine] doesn't cause autism ... and then you've got an out in the back of the thing, and you can't tell me, the committee chairman, under oath, that there's no causal link, because you just don't know, do you?" Burton asked Marie McCormick, MD, ScD, of the Harvard School of Public Health and IOM panel chairwoman.
"I don't know," responded McCormick after saying earlier that the door was still open and that the theory had not been disproved. Her brother, incidentally, has two autistic children.
It's estimated that the number of children affected by this condition has grown from 4 per 10,000 five years ago to one in 500 children today. The symptoms range from violent behavior to total withdrawal.
Burton's grandson Christian reportedly developed the disease after receiving vaccines that are routinely recommended by federal health officials. And the public figure has adopted the vaccine safety issue as a political and personal crusade.
The congressman was also angered that two of the report's reviewers are believed to have had financial ties to the pharmaceutical industry. The IOM's committee on immunization safety was created as an independent body without conflicts of interests.
Susanne Stoiber, the IOM's executive officer, said the reviewers only offered suggestions. They didn't change the report's basic conclusion. "To the best of our knowledge, aside from the fact that [the reviewers] may own mutual funds that hold pharmaceutical stocks, there is no reason to believe that there are any financial ties," she said.
Nonetheless, Burton insisted on seeing the financial records of the vaccine committee members, as well as the reviewers. He vowed to use his subpoena power if necessary.
Andrew Wakefield, MD, also testified at the hearing. The English scientist has his own theory about the relationship between the shot and autism. His studies of a small number of children suggest that a double-dose of the vaccine could lead to a low-level measles infection. He believes the measles virus could cause a leak from the bowel into the general system and ultimately the brain, causing a toxic reaction, in susceptible children, that could lead to autism.
Wakefield says the IOM panel requested information on his observations in a closed session, but it didn't wind up in the final report. At the time, his latest studies were still being reviewed for scientific publication, so he couldn't present them in public. When asked at the hearing if the MMR vaccine is as safe as it can get, he responded, "No, absolutely, not."
But Wakefield was contradicted by another English scientist, Elizabeth Miller, MD, head of that country's Public Health Laboratory Service. Her studies show there has not been an increase of such problems in the U.K. since the vaccine was introduced there.
"I don't think it would be profitable to hijack the research agenda to concentrate on answering [Wakefield's] question, which is derived basically from speculation ... and ... unpublished evidence," she says.
Burton raised additional concerns that some of the information clearing the vaccine in the IOM report came from Merck, the product's manufacturer.
During the hearing, several physicians whose children have autism told the committee about their ordeal. One of them is Sharon Humiston, MD. A former immunization scientist for the U.S. government, she says she doesn't believe that the MMR vaccine was responsible for her son Quinn's disease. But she's desperately looking for answers, particularly to one heartbreaking question.
"What is going to happen to Quinn after [my husband and I] die? What are we going to do now to help?" she asked tearfully.