In 1998, a doctor named Andrew Wakefield said that vaccines, like the one for measles, mumps, and rubella, might cause autism. This made a lot of people worried, and some didn't want to get vaccinated.

But later, many studies looked into this, involving millions of kids, and they found no proof that vaccines cause autism. The first study was taken back, and Dr. Wakefield lost his job because he didn't follow the rules and didn't tell the truth.

Most doctors and scientists agree that vaccines are safe and really important to keep everyone healthy. The problem is, sometimes people hear wrong information and get scared, so they don't want to get vaccinated. This can be a big problem because it can make diseases come back.

Doctors and experts say that vaccines are a good way to stay healthy and keep others safe too.