Victoria has recorded a slight rise in its daily COVID-19 cases, and infections in NSW continue to steadily decrease as attention turns to rolling out vaccine booster shots across the nation.
There were 1510 new cases reported on Tuesday by Victoria and four deaths.
There are now 817 Victorians in hospital with COVID, 147 of whom are in intensive care, with 88 of those on a ventilator.
However, new figures have shown three-quarters of over 16s in the state have been fully vaccinated.
In NSW, there were 282 new local cases and two from hotel quarantine, while there was one additional death.
Hospital admissions have decreased, down to 457, with 109 in ICU.
Vaccination rates continue to climb with the state now at 85 per cent of its over 16s being fully vaccinated.
Queensland also recorded two new COVID-19 infections, one of them a Gold Coast teenager who is a close contact of a household case, while the second is in home quarantine.
Health officials in the state also said a truck driver tested positive interstate but was infectious while in Queensland.
There were 12 new cases reported in the ACT, with the capital now at 89.3 per cent of its over 12s being fully vaccinated.
The new virus numbers come as focus turns to COVID-19 booster shots and their rollout to the general public.
Meetings were held on Monday by the national medical regulator's vaccine committee and the Australian Technical Advisory Group on Immunisation discussing whether to approve a third dose.
While booster shots have already been made available to severely immunocompromised Australians, they are yet to be approved for the general public.
Infectious diseases expert Peter Collignon said mixing and matching vaccine brands for booster shots would be "inevitable".
He told the Seven Network it was likely some Australians would get a different vaccine brand for their third dose compared to their first two when booster shots are approved.
"How you best mix and match we don't know yet, but we can get data from North America," Professor Collignon said.
"Summer is likely to have much less transmission than next winter, so we have got about four or five months to get an answer for this."
The medical regulator will be considering data surrounding booster shots from overseas before a final decision is made.
A spokeswoman for the Therapeutic Goods Administration told AAP an approval decision was being undertaken as a priority and was expected to be finalised in coming days.
It is likely mRNA vaccines, such as Pfizer and Moderna, would be predominantly used for the third vaccine doses.
Australian Associated Press
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