Australians with severely weakened immune systems will be offered a third coronavirus jab to maximise protection against the deadly disease.
The Australian Technical Advisory Group on Immunisation on Friday released new recommendations for all people aged 12 and above with certain conditions or undergoing specific therapies.
Up to 500,000 people will be able to receive a booster shot from Monday.
A Pfizer jab is preferred for people two to six months after their second dose with a minimum interval of four weeks in exceptional circumstances.
Severely immunocompromised people who received their second dose more than six months ago should get another injection as soon as possible.
ATAGI is expected to provide advice about booster shots for the wider population by the end of October.
Health Minister Greg Hunt said Australia had secured 151 million doses to enable a booster program.
"There's enough vaccine for every Australian to have first and second doses," he told reporters.
"There's enough vaccine for every Australian as they come due for boosters."
Booster shots will be made available to organ or stem cell transplant recipients, people with blood cancer and those receiving treatments that dampen their immune systems.
People living with HIV that is not controlled by therapy, receiving certain arthritis medications and those born with an immunodeficiency are also included.
Labor's health spokesman Mark Butler wants to know when frontline healthcare workers and older Australians will be eligible for booster shots.
"We've seen evidence that the immunity from those vaccines does start to wane after several months," he told reporters in Adelaide.
"Are we going to see, yet again, something that's too little, too late on booster shots?"
ATAGI is expected to provide advice on booster doses for healthcare workers, older adults and the general population in its next update.
Chief Medical Officer Paul Kelly said the general principle would be for people to receive an mRNA vaccine such as Pfizer or Moderna as their third dose.
"A third dose is likely, at this stage, to be the last dose we have to do," he said.
Professor Kelly believes coronavirus vaccines are unlikely to be like the annual flu jab.
He has also released a plan for health workers who come into contact with coronavirus to keep working rather than be isolated.
Australia has now vaccinated more than 60 per cent of its population aged 16 and above, while 81.5 per cent have receive at least one dose.
The health minister said the latest increase took Australia past the United States, Israel and the European Union on first-dose coverage.
Mr Hunt said Pfizer was in talks with the Therapeutic Goods Administration about applying for children aged five to 11 to be approved for vaccination.
Victoria reported 1838 new COVID cases on Friday, the highest single-day total of any state or territory since the pandemic began.
There were five more deaths across the state and 11 in NSW, which recorded 646 new local cases.
Canberra detected 40 more infections.
© AAP 2021