How immunisation works

Vaccines stimulate the body’s natural defences

Children come into contact with many germs, including bacteria and viruses each day and their immune system responds in various ways to protect the body. Vaccines strengthen the body’s immune system by training it to quickly recognise and clear out germs (bacteria and viruses) that the vaccination has made them familiar with.

When you’re vaccinated, your body produces an immune response. This is how your body defends itself against bacteria and viruses and other harmful substances.

When you come in contact with that disease in the future, your immune system remembers it. Your immune system responds quickly to prevent the disease from developing.

Without a vaccine, a child can only become immune to a disease by being exposed to the germ, with the risk of severe illness. Sometimes your child will need more than one dose of a vaccine. This is because a young child's immune system does not work as well as an older child or adult. The immune system of young children is still maturing.

Vaccination helps to protect the community from contagious diseases.

The National Immunisation Program has further details about how vaccines help immunity.

Page last updated: 01 Sep 2017