Everyone—babies, kids, and adults—needs vaccinations to stay healthy and help keep diseases from spreading. Vaccines are important for everyone in your family.

What is a vaccine? A vaccine helps your body fight off certain diseases. Most vaccines are given with a needle, but some can be taken as a liquid or spray. If you're scared of needles, your doctor might have tips to help you feel better about it.

How do vaccines work? Most vaccines use inactive (dead) or weakened bacteria to teach your body how to fight those germs. This way, if you ever come across the real germs, your body will be ready to fight them off. Some vaccines tell your body to make certain proteins that help you stay healthy, too.

Why are vaccines important? Vaccines help stop serious diseases, like whooping cough and measles, from spreading. Because of vaccines, these diseases are now very rare. Vaccines also help you avoid missing school or work, spending extra money on health care, and getting really sick.

Some vaccines need to be taken every year, like the flu shot. Others are needed at certain ages or for special reasons, like traveling to another country or working in healthcare.