Here’s What the Science Says About Vaccines

Where Did This Idea Come From?

To understand why these claims persist, it’s important to know their origin. In 1998, a discredited British doctor named Andrew Wakefield published a paper that linked the MMR vaccine to autism. It turned out his research was false and funded by lawyers suing vaccine companies. The paper was retracted¹, and the doctor lost his license. Unfortunately, the damage was already done with vaccination rates dropping^2,3, and measles outbreaks began to climb again⁴.

What Does the Science Say?

Since then, scientists all over the world have studied this question in depth. Here’s what they found:

• More than 70 studies have looked for any link between vaccines and autism.
• A small number of those studies claimed to find a connection, but most were later retracted for bad data or conflicts of interest.
• In contrast, over 40 high-quality studies involving more than 5.6 million people across seven countries found no connection between vaccines and autism.
  

These larger studies were carefully designed and reviewed by independent experts.

What About Vaccine Ingredients?

Over the years, people have raised concerns about ingredients like thimerosal (a preservative removed from most vaccines in 1999⁵) and aluminum additives (an ingredient that helps vaccines work better). These claims have also been studied.

• A Danish study of 1.2 million children found no link between aluminum in vaccines and autism nor any other health conditions⁶.
• Independent research continues to show that vaccine ingredients are safe at the levels used.