At 15 months old, Michelle Cedillo was a bright-eyed, cheery toddler who cooed her favorite words like “mommy” and “kitty.” That month Michelle had a routine vaccination against measles, mumps and rubella. She came down with a fever that lasted four days and, according to her parents, resulted in a drastic change. “She did not respond to her name any longer,” says her mother, Theresa Cedillo. “She didn’t look at us. She didn’t talk.”
Michelle was later diagnosed with a severe case of autism—the neurological disorder that affects one in 150 American children—and, 11 years later, her parents are still trying to figure out what went wrong. On June 11 a claim filed by the Cedillo family against the Department of Health & Human Services, which maintains a fund to compensate people injured by vaccines, went to trial in Washington, D.C. The family claims that thimerosal, a mercury-based preservative once common in childhood vaccinations (it was phased out starting in 1999 as a precautionary measure but is still used in some flu vaccines), in addition to their daughter’s MMR shot, somehow triggered her autism. Their case before the nation’s so-called vaccine court is the first of 4,800 claims linking autism and childhood shots to be heard by the three judges. The results are being closely watched by thousands of families desperate to understand what scientists have so far been unable to explain: What causes their children’s autism?
The debate has already turned bitter, including at the leading advocacy group, Autism Speaks, where cofounders Bob and Suzanne Wright have clashed with their daughter Katie, who insists vaccinations caused her own son’s autism. “There’s a lot of kids in this country who have literally been poisoned by the recommended vaccine program in the United States,” says Wendy Fournier of the National Autism Association. Nearly all academic and government scientists, though, say there is no link. A 2004 study by the Institute of Medicine’s Immunization Safety Review Committee reached the same conclusion. “We could find no evidence of a biological mechanism by which either thimerosal or MMR could cause autism,” says Dr. Marie McCormick of Harvard’s School of Public Health, who led the study.
While the search for a cause continues (see box), the arguments rage on. The Cedillos’ attorney Kevin Conway, whose firm is handling about 1,200 autism cases, says the mercury in thimerosal from numerous shots, for such diseases as hepatitis B and diphtheria, suppressed Michelle’s immune system at a vulnerable stage of development. Then, according to the family’s claim, Michelle received a measles vaccine in late 1995, which because of the child’s weakened immune system was able to travel through her bloodstream to the brain, where it caused inflammation and brought on autism. The family also blames the measles vaccine for Michelle’s severe gastrointestinal problems. Because of the thimerosal, says Conway, “she was unable to clear the measles virus in that vaccine [from her system].”
Attorneys representing the government are likely to attack the Cedillos’ theory on several fronts. Chemicals, including the small amounts of thimerosal once found in vaccines, are typically flushed from the body within a week, says Peter Hotez, chair of microbiology, immunology and tropical medicine at George Washington University. Dr. Samuel Katz, who helped develop the measles shot, says, “We have no evidence the measles virus persists in the intestines of anyone, even immune-deficient individuals.” (Neither Hotez nor Katz is involved in the Cedillo case.)
A verdict in the trial isn’t expected for up to a year. The Cedillos are optimistic. If they win, they stand to get compensation from the federal fund set up for people hurt by vaccinations. Claimants in non-autism cases have won up to $10 million—an amount that would certainly help. Theresa, 45, a homemaker in Yuma, Ariz., and her husband, Michael, 51, a utility worker, spent about $18,000 last year caring for Michelle, now 12, who can’t walk without assistance or talk but loves watching Teletubbies and listening to music. “I didn’t file this claim with the intent of saying, ‘See, I told you so,'” Theresa says. “I’m hopeful that something good will come out of it.”