Increase in autism troubling

Some parents link illness to vaccines, but doctors unsure

By TODD ACKERMAN and MARY ANN FERGUS
Copyright 2002 Houston Chronicle

Beaumont residents Mark and Darla Williford can tell you exactly when their infant daughter stopped making eye contact, learning new words and smiling for the camera.

It was shortly after her first birthday, on the day in November 1995 that Laura received four vaccines. That night, she had a fever and was agitated, common side-effects of vaccination. But the next six months were anything but typical: the girl acted strangely, flipping lights on and off, for example, and she would scream and laugh for no reason.

"It looked like she was going insane," said her dad.

In March 1999, Laura was diagnosed with autism, a devastating neurological disorder marked by jerky, repetitive movements, a lack of language skills and social withdrawal. A month after the diagnosis, Mark Williford found a report about a possible link between autism and childhood vaccines that contained a mercury-based preservative. His daughter's vaccines contained the preservative, called thimerosal; her symptoms matched those of mercury poisoning.

"I remember reading the symptoms and a cold chill went up my spine," Williford recalled. "I said, `This is what's causing it.' "

In Texas and around the world, more and more people are becoming convinced that autism can be caused by the vaccines supposed to protect them. The U.S. Food and Drug Administration and Centers for Disease Control and Prevention say there's no evidence to support the hypothesis, but thousands of parents have joined a worldwide legal campaign to hold pharmaceutical companies liable for injecting infants with a known toxin.

It might sound like ambulance-chasing lawyers and blame-happy parents except for one thing: Autism's exploding these days and no one knows why.

The explosion, a tripling over the last decade, suggests an environmental component that could be explained by increased mercury exposure associated with a rapid increase in vaccinations during the 1990s. The mercury has now been removed from most vaccines, but concern over a possible link to autism has led to congressional hearings, multimillion-dollar studies, and clusters of class-action lawsuits that one of the lawyers says "could be the biggest thing to come down the litigation pipeline ever."

There also have been declining immunization rates in some countries, raising fears among public health leaders that the allegations could undermine a vaccine program considered one of the great medical breakthroughs of the past century. Some scientists acknowledge that this fear threatens to stifle open inquiry into whether the concerns are legitimate.

For the most part, however, doctors seem confident that the allegations aren't legitimate.

"Vaccines have been tested every which way and no link to autism has ever come up," said Dr. Jane Siegel, a pediatrics professor at the University of Texas Southwestern Medical Center in Dallas, who has served on national advisory committees on vaccines. "They're safe."

Still, scientists are at a loss to explain the dramatic increase in the incidence of autism, which was not described until the 1940s and then was attributed to cold "refrigerator" mothers. That theory has been debunked and researchers are zeroing in on genetic causes, but the disorder is still poorly understood. There is no cure, though a new intensive therapeutic program is helping some children.

Once thought to occur in 1 of every 10,000 children, autism today is estimated to afflict 1 in 500. A California study last month that found a three-fold increase from 1987 to 1998 said the hike couldn't be explained away by statistical anomalies or different definitions or growing public awareness, but the study could offer no explanation. The increase in Texas was more than twice as large as in California.

There are two ways vaccines are alleged to play a role. One is that certain vaccines -- the measles, mumps and rubella (MMR) shot has attracted the most attention -- may themselves cause autism or other problems in a small percentage of sensitive people. A study in the New England Journal of Medicine, published Thursday, found no evidence to support the MMR theory, the latest in a series of such findings involving that vaccine.

The other theory involves thimerosal, which until recently was used in many vaccines to guard against contamination when pediatricians jab the same vial repeatedly to vaccinate one child after another. The amount of mercury in each shot was slight, but advocates of this theory say a dangerous amount could accumulate because the number of required vaccinations has mushroomed since the late 1980s as researchers have figured out how to prevent more infectious diseases -- a typical child now gets 32 doses of 12 vaccines by the age of 6; a 2-month-old may get five shots during one visit to the doctor's office.

Critics wonder if all that mercury was more than those little bodies could handle, whether the result is autism or some other crippling neurological disorder.

"It's outrageous to think that injecting a child with all that toxicity is an acceptable risk," said Bernard Rimland, director of the Autism Research Institute in San Diego. "It's also outrageous that despite such compelling evidence of harm, the medical community would subject children to it."

In 1999, the FDA concluded that infant children who receive the recommended series of immunizations are receiving more mercury than is considered safe by the U.S. Environmental Protection Agency and asked vaccine manufacturers to voluntarily phase out their use of thimerosal. The conclusion was later echoed by the CDC, pediatric organizations and a blue-ribbon panel of experts that reviewed all the existing studies on thimerosal and autism.

The manufacturers now say they're producing thimerosal-free vaccines, and a Texas Department of Health representative said the agency is confident of this. Believers in the mercury theory, however, are skeptical about whether all the old stuff is off the shelves.

For instance, it took an intense effort by Williford to get the Beaumont Health Department to replace its supply last year. The department finally agreed in August 2001, following six months of Williford's making requests, talking to his state representatives and appearing at City Council meetings.

For his and other families, the struggle was to understand what was happening. After her son was diagnosed with mild pervasive developmental disorder at age 2 1/2, autism a couple of years later, and then "severe autism," Spring resident Gina Shaw traveled to California in 2000 for a Defeat Autism Now conference.

There, she heard a speaker present new information suggesting a link between thimerosal and autism. Coming on the heels of a test that had revealed high levels of metals in her son's blood, the theory seemed persuasive.

Tears began running down Shaw's cheeks as she listened to the speaker. She grew angry that government agencies allowed the use of vaccines containing thimerosal. "I was mad as hell," she said, "because they did this to my baby."

Shaw and her husband, Darwin, can barely look at early photographs of Brett. They show a laughing child with twinkling blue eyes.

But in photos taken after his second birthday, Brett is stonefaced. He could barely sit still long enough to be photographed.

Now 10, Brett mumbles a few random words such as "bye" and "eat." He can follow simple instructions but doesn't understand everyday conversations between his parents and his 12-year-old sister, Brianna. He takes special-education classes and functions at a 2-year-old's level.

Unable even to write his name, Brett lives largely in a world of his own, entertaining himself with simple computer games or playing alone in a closet or tent.

The Shaws estimate that they've spent $50,000 on their child's care. (The Willifords have spent $60,000.)

In January, the Shaws filed a complaint with the U.S. Court of Federal Claims in Washington, D.C., under the National Vaccine Injury Compensation Program, which compensates people injured by routine vaccinations. The complaint was handled by Hitt, Patterson & Sell in Houston, one of four Texas firms leading the litigation onslaught.

Two other firms are also based in Houston -- Gallagher, Lewis, Downey & Kim and Williams & Bailey -- and one is a Dallas firm, Waters & Kraus.

The firms are part of two legal coalitions that estimate they have about 4,000 clients between them. The first lawsuit in a state civil court, filed by Waters & Kraus, concerns a Plano boy who had a growing vocabulary at 20 months, then lost all his language skills, was diagnosed with autism and found to have high levels of mercury exposure. The lawsuit is in Brazoria County, where one of the defendants, Dow Chemical Co., has a drug manufacturing plant.

Attorney Jeff Sell believes in the cases as a litigator and father. His 8-year-old twins have autism.

Sell cannot file a complaint through the Vaccine Court because those must be filed within three years of the onset of symptoms, and it was five years before he made a connection. But because the Vaccine Court strictly limits damages, the potential for bigger money is in civil courts anyway.

"With as many as 200,000 possible cases of developmental disorders that could be tied to vaccines, this could turn out to be one of the biggest mass tort cases ever in the United States," said Michael Williams, chairman of the Mercury Vaccine Alliance, which already has filed seven class-action lawsuits around the country. "But we won't know for two or three years."

Complicating the plaintiffs' case is that the children could have been exposed to mercury from other sources, such as fish or dental fillings. Even if science ultimately finds a link between mercury and autism, it might not be clear whether the culprit was the vaccines or exposure from the mother's fillings or consumption of fish while the child was in the womb.

At the moment, of course, the biggest threat to the lawsuits' success is the lack of science backing them, say legal observers. Scientists acknowledge that mercury is a potent neurotoxin known to damage the brains, nervous systems and immune systems of unborn children, but beyond that little is certain.

For one thing, although autism sometimes can be detectable as early as 6 months, it more often appears to hit later, at 1 1/2 to 2 years, and after the child had appeared to be developed normally. Those skeptical of a vaccine link say it is just a coincidence that symptoms appear at the same time the MMR vaccine is given.

For another, there have been few well-designed studies looking into the mercury allegation. The blue-ribbon panel of experts assembled to look into the matter called the idea that thimerosal poses a significant threat to the developing brain "biologically plausible" but said none of the existing studies had been designed well enough to produce evidence of a link.

Both sides in the debates have seized on the panel's report.

(The evidence is much better that the MMR vaccine doesn't cause autism, said the head of the panel. The New England Journal of Medicine study published Thursday tracked 500,000 Danish children born between 1991 and 1998 and found no statistical difference in autism between those who received the MMR vaccine and those who didn't. The vaccine has never contained thimerosal.)

Typical of the contentiousness surrounding the issue was a July 2000 congressional hearing convened by U.S. Rep. Dan Burton, R-Ind., whose autistic grandson seemed healthy and talkative until getting a series of vaccinations at one time. Rep. Henry Waxman, D-Calif., complained that the hearing was unfairly stacked with parents and experts alleging a connection between vaccination and autism, and the only thing committee members could agree on was the need for further study of the issue.

"The fact is, there just hasn't been much done in this area," said Irva Hertz-Picciotto, a professor of maternal and child health at the University of California-Davis School of Medicine, recently awarded a federally funded center to study the issue. "We don't know much about the epidemiology of autism, let alone whether mercury could foster it."

This much is known about autism: There's a genetic susceptibility -- the risk increases for younger siblings of autistic children -- that scientists think involves 10 to 20 genes. But the environment also can play a role: It was more common in babies born to mothers who took thalidomide or had rubella during pregnancy. New studies will look at the interaction between genes and environment.

One theory is that some autistic children lack a protein called metallothionein, which the body needs to excrete toxic metals, such as mercury, before they damage the brain and gut. In one study of 503 children with autism or other pervasive developmental delays, all but four were missing the protein. But the theory is considered speculative at this point.

The problem with the few studies that have been done is that they're retrospective, not prospective -- they ask parents to recall the vaccine shots and onset of autism, a method considered unreliable. The new studies will track babies receiving vaccines to determine who develops autism and who doesn't; and will analyze blood, urine and hair samples of different population groups (those with autism, those developing normally and those diagnosed as retarded but not autistic) for environmental agents and genetic information.

Over it all looms the vaccine program -- a savior to some, a sacred cow to others. Those who worry about the effect of the allegations say society is vulnerable because people don't know what it was like before vaccines, when diseases such as diptheria and polio claimed thousands of lives a year.

Others, like Baylor College of Medicine vaccine researcher Bonnie Dunbar, worry that the program's special status is interfering with the scientific process. After adverse reactions to the hepatitis B vaccine by family members and co-workers convinced her to research the theory that in some people the immune system attacks itself rather than the vaccine's viral material, drug companies denied her access to materials and the government turned down her requests for grant money.

"No one wants to hear anything bad about vaccines," said Dunbar, a professor of molecular and cellular biology who has spent most of her career developing vaccines. "Health institutes' and pharmaceutical companies' lack of support for research into adverse reactions to some vaccines is appalling."