Many large studies have found that vaccines do not cause autism. The idea that vaccination caused autism was attractive to some people who wanted to find a clear cause. However, this idea arose from a few studies that were badly conducted and have since been proven wrong. Current research suggests that autism cannot be explained by a single cause, but is probably due to a combination of developmental, genetic and environmental factors.
DownloadA number of high-quality studies have compared the health of large numbers of vaccinated and unvaccinated children over many years. The largest study included 537,303 children born in Denmark and found that unvaccinated children were just as likely to develop autism as vaccinated children.1 When the results of this study were combined with the results of nine other studies to include medical information from nearly 1.5 million children living all around the world, researchers were able to confirm that vaccination could not be causing autism.2
Some people think there is a connection because a British a research group, led by Andrew Wakefield, suggested that some children who had received the measles-mumps-rubella (MMR) vaccine went on to develop bowel disease and developmental disorders such as autism.3 The results of the research, which had included only twelve children, were published in a respected medical journal in 1998. However, in 2004 the authors retracted their claim that there was any association between vaccination and autism. The paper was withdrawn from the journal in 2010 after the General Medical Council found that results reported in the paper had “proven to be false”.4 The journal printed an apology.5
After it became clear that the MMR vaccine was not the problem, some people suggested a preservative sometimes used in vaccines packaged in multi-dose containers might be linked to autism. The preservative, called thiomersal, is a salt that contains a tiny amount of mercury. The mercury salt in thiomersal (ethylmercury) is not like the mercury compound (methylmercury) that accumulates in the human body.
None of the vaccines normally given to children in Australia are packaged in multi-dose containers, so none of them contain thiomersal or any other form or mercury.
You can’t get separate vaccines for measles, mumps, and rubella for your child because they are not available in Australia. Some people suggest using separate vaccines for measles, mumps, and rubella instead of the combined measles, mumps, and rubella (MMR) vaccine. Medical researchers are confident that vaccines don’t cause autism.
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