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Can vaccines cause autism?

Question: 

Can vaccines cause autism?

Answer: 
  • Many large studies have found that vaccines do NOT cause autism.
  • A number of credible studies have compared the health of vaccinated and unvaccinated children over many years. They have found that unvaccinated children were just as likely to develop autism as vaccinated children.
  • It is not known exactly why some children develop autism; current research suggests that both genetics and environment likely play a role.
  • Because children with autism are often diagnosed after the age when they receive some vaccines, this has led some people to think that vaccines cause autism. But just because one thing happens after another, it does not mean there is a link between them.
  • Much of the controversy around a possible link between the MMR vaccine and autism came from a single small study published in 1998.
  • The study was found to be fraudulent and was withdrawn by the journal that published it.
  • Many large, high-quality scientific studies around the world have since taken place and have found no link between the MMR vaccine and autism. A summary of several of these studies and their conclusions are available.
Date last reviewed: 
Monday, Jan 31, 2022