Australia's coronavirus booster shot program is being rolled out.
Here's everything you need to know about getting your third vaccination.
Covid booster eligibility
You are eligible for a booster if you are 18 or over - if you are under that age you do not yet require a booster.
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You need to have had your second dose of any vaccine at least five months ago.
Amid the emergence of the new Omicron variant, that has been brought forward from six months.
You can check when you had your last shot on your vaccine certificate.
Booster doses are not mandatory, but are recommended by the Australian government,
Can you get a Moderna booster shot if you've had Pfizer or AstraZeneca jab?
Australia is using three COVID-19 vaccines- Pfizer, Moderna and AstraZeneca- although the latter is being phased out.
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You can have the Pfizer or Moderna vaccine as a booster dose regardless of which vaccine you had for your first two doses.
The government says you can have AstraZeneca if you can't have the others for medical reasons, or if you had that for your first two.
It doesn't matter which brand you have.
Do you need two doses of the Pfizer and AstraZeneca COVID-19 vaccine to get a booster shot?
Yes, your booster shot is also known as a third vaccination.
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Where/how to book booster shots
You can book via the government site here.
Doctors surgeries, pharmacies and also state vaccination hubs are all now giving out booster shots.
Boosters remain free of charge.
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Omicron severity against booster shots
Studies are still under way into how vaccines protect against the new Omicron variant, which was first reported in southern Africa.
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Chief Medical Officer, Dr Brendan Murphy, said boosters have been made more important by Omicron.
"We do believe that as one gets towards six months, their waning immunity of the primary vaccination means that a booster will be very important to continue that protection against this variant," he said.
"We're still learning about Omicron, but that evidence seems to be coming out of the lab."
Why get a booster
Two doses of COVID-19 vaccine provide very good protection, especially against severe disease, according to the Australian Government.
A booster dose will make sure the protection from the first dose is even stronger and longer lasting, and should help prevent spread of the virus, it says.
Last week, Health Minister Greg Hunt said almost 700,000 people had already had their boosters in Australia.
By the start of January, 4.1 million Australians will be eligible to have the booster.
For more details visit the official government website
