Vaccination or immunisation – what’s the difference?

Vaccination is when you get a vaccine by injection, drops in the mouth, or swallowed. When you have a vaccine, your immune system makes antibodies that fight off infection or disease. Immunisation is the process of both getting a vaccine and developing immunity to a disease as a result. There are also immunisation treatments available that contain pre-made antibodies. These treatments provide almost immediate protection against certain diseases once administered.

How vaccines work

Vaccines contain small amounts of dead, weakened or partial virus or bacteria. When you have a vaccine, your immune system makes antibodies. These fight off infection and disease in your body.

If you catch the virus or bacteria in the future, your body quickly produces antibodies to stop the disease or reduce its impact. Your body produces these quicker than if you haven’t had a vaccination.

Once you have a vaccination, you have a much better chance of not developing the disease the vaccine was for. If you do develop the disease, your illness will most likely be less severe.

Watch our short video and learn more about how vaccines work.

Vaccines are safe, clever, and help protect us from serious diseases like measles, whooping cough or the flu.
But how do they work?
Well, let's take a look at our immune system first.
Every day, we come into contact with germs.
But thanks to a healthy immune system we can usually avoid getting sick.
You see, our immune system is on constant alert for viruses and bacteria trying to enter our body.
If they do get in, white blood cells surround them and create antibodies, that lock onto and destroy the germs.
Vaccines work in the same way by, stimulating the immune system into triggering this same response.
The vaccines seem like viruses or bacteria, but actually, their non-harmful forms or parts of the viruses or bacteria, which are just enough to trigger our immune response.
Our antibodies then destroy it without us getting sick.
These antibodies stay in our body for some time.
So, in the future...
If we do come into contact with the real virus or bacteria, our immune system remembers it, and how to fight it.
Think of vaccines as battle training for our immune system!
That's why vaccines are our best form of protection.

How immunisation works

Immunisation helps your body fight diseases. If you have contact with someone who has a disease you’ve had a vaccine for, your immune system remembers it. In most cases it stops the disease developing and reduces its impact of serious complications and outcomes such as severe illness, death or disability.

How we know vaccines are safe

The Therapeutic Goods Administration (TGA) regulates all medicines in Australia, including vaccines.

Before they approve a vaccine for use in Australia, it’s tested on thousands of people in clinical trials for safety and effectiveness.

The TGA also continuously monitors vaccines to make sure they’re safe.

The Australian Academy of Science reviews clinical trials that investigate the safety of vaccines. You can find out about vaccine safety on their website.

Vaccine reactions

Serious reactions are extremely rare.

Minor reactions include short term redness, swelling, pain and mild fever. There are things you can do if you or someone else has a reaction including:

  • taking paracetamol for fever or discomfort, make sure you take them as directed on the packet
  • consulting your doctor if the reaction persists
  • seeking urgent medical advice if a serious or unexpected reaction occurs.

If you have questions about possible side effects from vaccines, speak to your doctor or health provider.

Where to get vaccinated

Getting vaccinated is easy. You can get most vaccines from your GP or other vaccination service providers. Find out where to get vaccinated.

Last updated: March 2024