Is there a connection between vaccines and autism?
No. Autism is a condition that affects the brain and makes communicating and interacting with other people more difficult. The cause(s) of autism — also known as autism spectrum disorder (ASD) or pervasive developmental disorder (PDD) — is unknown. However, genetics, differences in brain anatomy, and toxic substances in the environment are thought to contribute to children developing the condition.
So how did the idea that vaccines play a role get started? Much of the blame lies with a study published in 1998 that suggested that the MMR (measles-mumps-rubella) vaccine, or infection with the naturally occurring measles virus itself, might cause autism. Since then, numerous scientific studies have shown that there is no link between vaccines — or any of their ingredients — and autism. And the research used in that study was found to be false, the doctor who wrote it lost his medical license, and the medical journal that published it retracted the paper (this means that they believe it never should have been published).
Even with the overwhelming evidence that vaccines are safe and effective, some parents still decide not to have their children vaccinated or to delay vaccinations. But this is extremely risky because vaccine-preventable diseases like measles are still very much around. So if an unvaccinated child gets one of these preventable diseases, other people around that child could get very sick.
Sometimes, kids can have a reaction to a vaccine like a mild fever or rash. But it's clear that the risk of serious reactions to the MMR and other recommended vaccines is small compared with the health risks associated with the often-serious diseases they prevent.
If you have concerns about any vaccine recommended for your child, talk to your doctor. Ask about the benefits and risks of each vaccine and why they're so important for safeguarding your child's health.
Reviewed by: Rupal Christine Gupta, MD
Date reviewed: February 2015