Australians aged 30 and older are now eligible for a fourth dose of the COVID-19 vaccine.
The decision comes after recommendations from the Australian Technical Advisory Group on Immunization ATAGI were accepted by the government earlier this afternoon.
Health Minister Mark Butler announced on July 11 that 7.4 million people can get their fourth dose from July 11.
Here's where things are currently at.
Who is eligible for a fourth COVID jab?
ATAGI said the shot was recommended for people over 50, while people aged 30 to 49 may choose to have a fourth dose.
Australians under 65 were strongly urged to get the booster shot, according to Butler.
He said there was an open question about whether young, healthy people needed it.
ATAGI did not support making the fourth dose available to healthy adults under the age of 30 years, as it was not clear whether the benefits outweighed the risks in this population group.
From Monday, July 11 to 11 there will be a fourth dose for those who are newly eligible.
How long does it take to wait for my last dose?
If you've had COVID- 19 since receiving your booster shot, you have to wait four months after you've acquired the infection.
People may be able to receive the vaccine after a shorter period in special circumstances, but that wait time cannot be less than three months.
Which vaccine should I get for my fourth shot?
Pfizer and Moderna, both of which are mRNA vaccines, are ATAGI's preferred vaccines.
AstraZeneca vaccine can be used when someone can't have an mRNA vaccine for medical reasons or if they decline one.
Novavax is approved to be administered as a fourth dose, but only if no other vaccine is considered suitable for that person.
How many people have had three or more doses?
In Australia, almost 14 million people aged 16 and over have received three or more doses of the COVID- 19 vaccine.
According to the data from the Australia Immunisation Register, it's estimated that about 70.6 per cent of people are currently eligible for the booster shot.
How many people have had four or more doses?
There are more than 2.1 million people aged 65 and older.
The number of people who are eligible for a winter dose changes from day to day because people are only eligible for the winter booster four months after they received their third dose.
Why weren't fourth doses recommended for everyone before?
In a statement, ATAGI said there was insufficient evidence of the benefits of an additional booster dose, and they would recommend them for people who don't fall into the categories listed above.
The statement says that protection against infection wanes after the first booster dose.
The protection against severe disease rather than all infection is relatively well maintained, especially in young healthy populations. ATAGI is saying that while people outside the four groups may get sick from COVID - 19, there is a lower risk that they'll get seriously ill from the virus.