No. One of the most frequent concerns expressed by some parents is that certain vaccines might cause autism. Please know there is absolutely no credible medical or scientific evidence to support any link between vaccines and autism. In fact, numerous credible medical, science-based studies have shown that there is no link between receiving vaccines and developing autism. You can read more about these studies on the Centers for Disease Control and Prevention website, the Children’s Hospital of Philadelphia website and the Autism Science Foundation website.

Concerns about autism and vaccines typically center on three areas:

  1. The combination measles-mumps-rubella (MMR) vaccine
    In 1998, a British researcher named Andrew Wakefield raised the notion that the MMR vaccine might cause autism. In the medical journal The Lancet, he reported the stories of eight children who he claimed developed autism and intestinal problems soon after receiving the MMR vaccine. It is important to know that the Wakefield study was later retracted for scientific misconduct, as his studies were exposed as fraudulent and his data misrepresented.

    However, to test Wakefield’s discredited claims, researchers performed a series of studies comparing hundreds of thousands of children who had received the MMR vaccine with hundreds of thousands who had never received the vaccine. They found that the risk of autism was the same in both groups. The MMR vaccine, in fact, did not cause autism. Some parents wary of the safety of the MMR vaccine stopped getting their children immunized. As immunization rates dropped, outbreaks of measles and mumps led to hospitalizations and deaths that could have been prevented. Read the scientific studies on the Autism Science foundation website.

  2. Thimerosal, a mercury containing preservative previously contained in several vaccines
    Several studies have shown that thimerosal in vaccines does not cause autism. Thimerosal is a mercury-containing preservative that was used in vaccines to prevent contamination. Thimerosal is no longer used as a preservative in any childhood vaccine except for the influenza vaccine. Attention by the news media has caused some parents to fear that thimerosal contained in vaccines might have harmed their children. Addressing these concerns, scientists performed several studies to determine whether thimerosal causes autism. Hundreds of thousands of children who received thimerosal-containing vaccines were compared to hundreds of thousands of children who received the same vaccines free of thimerosal. The results were clear: The risk of autism was the same in both groups; thimerosal in vaccines did not cause autism. Read the scientific studies on the Autism Science foundation website.
  3. Concern that babies receive too many vaccines too soon
    Before they are licensed, new vaccines are tested alone or in combination with existing vaccines. These studies determine whether new vaccines change the safety and effectiveness of existing vaccines and whether existing vaccines affect the new vaccine. These studies are performed every time a new vaccine is added to the existing vaccination schedule.

Every day, a healthy child’s immune system successfully fights off millions of antigens—the parts of germs that cause the body’s immune system to go to work. Vaccines contain only a tiny fraction of the antigens that babies encounter every day in their environment, even if they receive several vaccines on one day.

  • Kids are exposed to 2,000 to 6,000 antigens every day.
  • A strep throat infection, for example, exposes children to at least 25 to 50 antigens. That’s comparable to the antigens in the vaccines that infants get at their two-month visit–the DTaP, IPV, HepB, Hib, and rotavirus vaccines combine to just 54 antigens.

And even though children receive more vaccines to protect against more diseases now compared to 20 years ago, the actual number of antigens in vaccines is dramatically less than decades ago because vaccine technology has improved, making vaccines more efficient.

  • With the 1980 immunization schedule, vaccines contained more than 15,096 antigens.
  • Today’s vaccines contain only 177 antigens in 12 vaccines that protect children and teens against 16 vaccine-preventable diseases.

Here is a list of 4 of the more than 20 reputable studies that have found no relationship between MMR vaccine and autism. These studies illustrate the variety of methods that have been used to investigate whether MMR vaccine is linked to autism.

Immunization Safety Review: Vaccines and Autism.
Institute of Medicine. The National Academies Press: 2004

Lack of Association between Measles Virus Vaccine and Autism with Enteropathy: A Case-Control Study
by Mady Hornig et al. PLoS ONE. September 2008.

Age at First Measles-Mumps-Rubella Vaccination in Children with Autism and School-Matched Control Subjects: A Population-Based Study in Metropolitan Atlanta
by Frank DeStefano et al. Pediatrics. February 2004.

A Population-Based Study of Measles, Mumps and Rubella Vaccination and Autism
by Kreesten Meldgaard Madsen et al. New England Journal of Medicine. November 7, 2002.

CDC: Vaccines Do Not Cause Autism
Children’s Hospital of Philadelphia: Vaccines and Autism
Children’s Hospital of Philadelphia: Vaccine and Autism Q&A