Australia could start a population-wide coronavirus vaccine booster program before the end of the year with aged care residents in line for third jabs within weeks.
The nation reached a major vaccination milestone on Wednesday of more than 70 per cent of people aged 16 and above now fully vaccinated.
As the rollout ploughs on, attention is shifting to boosting people's protection in coming months.
People in nursing homes are expected to start receiving boosters from the second week of November subject to approval from the medicines regulator and expert immunisation panel.
Health Minister Greg Hunt believes the general population could start receiving third injections later this year.
"Would I like to see it commence this year and do I expect it to commence this year? Yes, and yes," he told reporters in Canberra.
The Therapeutic Goods Administration and Australian Technical Advisory Group on Immunisation are preparing advice on boosters for the wider population.
About 500,000 people with severely compromised immune systems have started receiving third doses.
Chief Health Officer Paul Kelly signalled people who were immunised against coronavirus at the start of the rollout would be the first to receive boosters.
"They will be the first in line because they are now six or more months after that second dose," he said.
Professor Kelly met with ATAGI on Tuesday when evidence from booster programs around the world was considered.
"We are able to look at the data that had come out from Israel," he said.
"It very much confirms this is safe, it is effective in all age groups for both decreasing infection as well as severe disease and, for the older age groups, prevention of death."
People who received AstraZeneca in their initial two-dose course are likely to receive Pfizer or Moderna as their booster.
Opposition health spokesman Mark Butler said health, border and quarantine workers should join the booster program at the same time as aged care.
"Every step of the way, Scott Morrison has been months and months behind the rest of the developed world," he told reporters in Adelaide.
"The Australian people can't afford for him to bungle boosters as well."
Charities and the World Health Organisation have opposed boosters in wealthy countries while poorer nations are still desperate for first rounds of vaccines.
Infectious diseases expert Robert Booy said Australia's booster program was not urgent given Papua New Guinea was fighting a major outbreak with a vaccination rate of under five per cent.
"They've got hundreds of thousands of cases and deaths," he told the Nine Network.
Professor Booy said vaccinating PNG would save move lives and help prevent new coronavirus variants.
"We'd be stopping a mutation. A mutation in Papua New Guinea which is a canoe ride away from Australia," he said.
"That is a way to stop further problems with COVID, to help our neighbours, to help ourselves.
Victoria recorded 1841 new local coronavirus cases and 12 deaths on Wednesday.
Seven people died in NSW where there were 283 more infections.
Australian Associated Press