It has been quite awhile since we revisited the Land of Pharma. This time, I am only putting forth some good information published in the Wall Street Journal on 03 Feb 2010:
Lancet Retracts Study Tying Vaccine to Autism
By Shirley S. Wang
The study that first suggested a link between vaccines and autism and spurred a long-running, acrimonious debate over the safety of vaccines has been retracted by the British medical journal that published it. The withdrawal supports the scientific evidence that vaccinations don't cause autism, but isn't likely to persuade advocacy groups that believe in a link.
A new autism study shows clusters of high autism rates in parts of California. WSJ's health columnist Melinda Beck joins Simon Constable on the News Hub with more.
The 1998 study of 12 children triggered worry among British parents that the measles-mumps-rubella vaccine caused autism, and many decided not to immunize their children against measles, according to Richard Horton, editor in chief of the Lancet, which issued the retraction Tuesday. He called the study the "starting pistol," though not the only cause, of the controversy.
Concern about the safety of vaccines, particularly regarding the preservative often used, thimerosal, which contains mercury, spread to the U.S. as well. Research has shown that as many as 2.1% of U.S. children weren't immunized with the MMR vaccine in 2000, up from 0.77% of children in 1995, according to a 2008 study published in Pediatrics.
"This retraction by the Lancet came far too late," said Paul Offit, chief of infectious diseases at Children's Hospital of Philadelphia and a coinventor of a vaccination for babies against a gastrointestinal virus, Rotateq, that is marketed by Merck & Co. "It's very easy to scare people; it's very hard to unscare them."
A widely cited 2004 statistical review of existing studies by nonprofit health-information provider the Institute of Medicine, which traced the vaccine theory back to the Lancet study, concluded there was no causal link between the MMR vaccine and autism. Some autism activist groups, however, continue to advocate against vaccinations for children, despite the lack of scientific evidence for such a link.
"Certainly the retraction of this paper doesn't mean that MMR doesn't cause autism and it's all a farce," said Wendy Fournier, president of the National Autism Association. It is "possible" that the MMR vaccine causes autism, she said, but "the science is not there in terms of the mechanism." The concern is that measles virus has been found in children's intestines after vaccination, said Ms. Fournier.
"No one is anti-vaccine," she said. "It's a matter of having vaccines be as safe as they can."
A study published in 2008 by researchers from several universities and the Centers for Disease Control and Prevention examined children with gastrointestinal problems who had autism compared with those who didn't have autism. They concluded there wasn't any evidence that the vaccine was responsible for autism.
Ten of the 13 authors of the original paper, all of whom were researchers at the Royal Free Hospital and School of Medicine in London, partially retracted the paper in 2004. However, the first author, Andrew Wakefield, didn't. Dr. Wakefield, who is now at the Thoughtful House Center for Children in Austin, Texas, didn't immediately return phone calls seeking comment.
"Many consumer groups have spent 10 years waging a campaign against vaccines even in the face of scientific evidence," said Dr. Horton of the Lancet. "We didn't have the evidence back in 2004 to fully retract the paper but we did have enough concern to persuade the authors to partly retract the paper."
The Lancet decided to issue a complete retraction after an independent regulator for doctors in the U.K. concluded last week that the study was flawed. The General Medical Council's report on three of the researchers, including Dr. Wakefield, found evidence that some of their actions were conducted for experimental purposes, not clinical care, and without ethics approval. The report also found that Dr. Wakefield drew blood for research purposes from children at his son's birthday party, paying each child £5 (about $8).
The Lancet's Dr. Horton said the journal was particularly concerned about the ethical treatment of the children in the study, and that the children had been "cherry-picked" by the study's authors rather than just showing up in the hospital, as described in the paper.
The authors "did suggest these children arrived one after another and this syndrome was apparent, which does lead you to think this is something serious," said Dr. Horton.
"I hope this brings closure to this controversy," said Fred Volkmar, an autism researcher and professor of psychiatry at the Yale Child Study Center who wasn't involved in the Lancet study. "My fear, unfortunately, is that this won't totally allay the fear of all parents."
In the 1998 paper, Dr. Wakefield and his colleagues described 12 children with gastrointestinal problems. Eight experienced symptoms that were thought to be related to the MMR vaccine, according to their parents or a doctor, and nine of the 12 children exhibited autistic behaviors.
Dr. Wakefield has been outspoken about his concern about the measles vaccine. He has continually pushed the view that the vaccine caused autism, said Greg Poland, professor of medicine and infectious diseases at the Mayo Clinic and director of the vaccine research group in Rochester, Minn.
"With the retraction, the hypothesis that he put forward has been debunked," said Dr. Poland.
1 year ago
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