Some Australian teenagers could receive their COVID-19 booster within days after approval cleared a major hurdle.
But NSW Health Minister Brad Hazzard has blamed "confusing" messaging on booster timeframes for slowing the national rollout, with over a third of eligible Australians yet to receive third dose.
The Therapeutic Goods Administration on Friday granted Pfizer provisional approval to offer a third dose to 16- and 17-year-olds, two months after the nation's booster program began.
Health Minister Greg Hunt on Friday described the development as "an important next step", with the Australian Technical Advisory Group on Immunisation working through final approval.
"We are hoping to receive the ATAGI advice within the next week, if not earlier. And if that's a positive then we can make this available immediately," he told reporters.
"It's available widely, we have doses distributed that are available being drawn on daily. So if we receive advice, then it will be authorised for approval the next day."
If approved, teenagers who received any vaccine would be eligible to receive a Pfizer booster. The cohort will receive the same dosage as adult Australians.
Pfizer was already administered as a booster to 16- and 17-year-olds in Israel, the US, and the UK.
Australia's chief nursing and midwifery officer, Professor Alison McMillan, said while young people accounted for fewer hospital admissions, boosters in the age range were vital.
"I know they are often hearing people say that this is a mild disease and you shouldn't worry, but you should, and you should make sure you do all you can to protect others," she said.
Authorities have warned boosters were particularly important after the highly-infectious Omicron variant of COVID-19, which reduced the efficacy of a two-dose course.
Data suggested the variant, which has spread rapidly across Australia since December, provided some immunity against severe illness from reinfection.
But experts have warned reinfections remained a threat with the Delta strain continuing to circulate. Mr Hunt urged Australians who had recovered from COVID-19 against complacency.
"If you have had Omicron, the simple message is: you still need to be boosted," Mr Hunt said.
"We want all Australians to come forward to be boosted. Once you've cleared your symptoms, then it's appropriate for you to come forward, so long as you are eligible for your dose."
Professor McMillan said COVID-19 patients should come forward for a booster as soon as they stopped displaying symptoms.
MORE COVID-19 NEWS:
Over a third of eligible Australians - more than 3.6 million - were yet to receive a booster.
Wait times for third doses have been slashed progressively from six months to four months since December. They will be cut to three months from Monday.
NSW Health Minister Brad Hazzard suggested mixed messaging from federal authorities was partly to blame for slow uptake.
"The TGA and the special advisory group to the federal government were telling us that we can have the booster five months after we had had our second shot, then it moved to four months, then it moved to three months," he told the ABC.
"I think that's been very confusing for most people."
Mr Hazzard also joined Victoria Premier Daniel Andrews in calling for 'fully-vaccinated' to be redefined as those who had received a third dose.
Mr Andrews unsuccesfully lobbied national cabinet to adopt the new definition on Thursday. The federal government insisted it would not pre-empt advice from ATAGI, which was working through the issue.
Prime Minister Scott Morrison also defended the federal government's handling of aged care facilities, maligned during the deadly 2020 Victorian outbreak.
Mr Morrison insisted aged care residents were a "key focus" of the Commonwealth, with 86 per cent of having received a booster visit, and backed under-fire Aged Care Services Minister Richard Colbeck.
Mr Colbeck declined to appear before a COVID-19 committee, citing the demands of the Omicron wave, but was later found to have attended an Ashes Test match in Hobart.
Mr Morrison said he understood the criticism, which Mr Colbeck had "taken on board".
"I know what he does each and every day or the welfare of people living in our residential aged care facilities, and he'll take the criticism on the chin and he'll get back to work."
Our coverage of the health and safety aspects of this outbreak of COVID-19 in the ACT is free for anyone to access. However, we depend on subscription revenue to support our journalism. If you are able, please subscribe here. If you are already a subscriber, thank you for your support. You can also sign up for our newsletters for regular updates.