Vaccines prepare your body to fight off harmful bacteria and viruses that make you sick.  How exactly do they do this?

• Vaccines contain harmless versions of germs or pieces of germs that teach your immune system how to protect you from disease.
• This process trains the immune system to remember the germ so it can fight off any real germs it may encounter. Once your immune system learns how to fight a disease, it can give you protection for life.
• It’s much safer for your immune system to learn how to protect you from disease through vaccination than for you to catch the disease itself.
• Having a vaccine not only protects you from disease, it also protects those around you — your family and your community.
• If enough people are vaccinated, it’s harder for the disease to spread to those people who cannot be vaccinated — such as people who are immunocompromised or too young to be vaccinated.