"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a link between vaccines and autism and spurred a long-running, acrimonious debate over the safety of vaccines has been retracted by the British medical journal that published it.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.
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."