Seven Australian cities are now in lockdown as authorities scramble to prevent spread of the highly contagious Delta coronavirus variant.
Officials reported a slight case rise on Wednesday, to over 200 cases.
Near half the population - over 12 million people - are under stay-at-home orders in Sydney, Brisbane, Perth, Darwin, Townsville and the Gold Coast.
On Wednesday, the outback town of Alice Springs also entered a snap lockdown after cases emerged in South Australia.
Local officials are concerned the virus could spread to nearby vulnerable Aboriginal communities.
Across the country on Wednesday, state leaders said they were facing a "pressure cooker situation" as new cases emerged.
Many have urged faster vaccinations as just 5% of the population remains vaccinated.
But messaging about the nation's main vaccine, the AstraZeneca jab, has been confused. On Wednesday, Queensland and Western Australia state premiers contradicted Prime Minister Scott Morrison's direction that people under 40 could get the jab.
How Delta burst Australia's Covid bubble
After months where it had nearly eradicated the virus, the Delta outbreaks have shocked Australia out of its previously relaxed lifestyle.
The variant has sprung up in five of its eight states and territories, just a fortnight after the first cluster took hold in Sydney.
For the past year, Australia has enjoyed near-zero transmission rates, recording just one Covid-related death this year.
It had prevented wider community transmission through measures including closed borders, hotel quarantine and aggressive tracing systems.
But leaks from hotel quarantine have highlighted gaps in the defences. That's sparked a blame game between state and federal leaders.
Prime Minister Scott Morrison's rollout of the nation's vaccine programme has also been severely criticised.
The low rate has been attributed to supply problems and public concern around the AstraZeneca jab and its rare blood clotting risk.
Spike in Australians rejecting AstraZeneca vaccine
What's gone wrong with Australia's vaccine rollout?
On Monday, Mr Morrison opened access to the vaccine to people aged under 40 - but that advice has not been endorsed by state governments or the Australian Medical Association.
Critics say a lack of public health messaging has exacerbated widespread hesitancy over the jab.
On Wednesday, the Queensland state government lashed the federal government for confusing messaging, and said it did not endorse AstraZeneca for young people.
It also warned it was due to run out of its Pfizer supplies in eight days - and said its request for more stock from the government had been turned down.
Calls to tighten borders
Queensland Premier Annastacia Palaszczuk also called for a crackdown on the number of international arrivals, after noting the state's new Delta cases stemmed from a business traveller flying between Indonesia and Brisbane who had infected a hospital receptionist.
Queensland plunged three cities - Brisbane, Townsville and the Gold Coast- into a three-day lockdown on Tuesday following the case detection.
"The person who brought the virus into Queensland was a regular traveller, not a vulnerable Australian returning home...and I honestly think we need a serious discussion about ensuring that people are vaccinated coming into this country," said Ms Palaszczuk.
"We have got to minimise the risk. We are at a pressure cooker moment at the moment. Right across Australia, it's like a pressure cooker."
Western Australia and Victoria have also called for a reassessment of the numbers of people allowed into the country.
New South Wales recorded 22 new cases on Wednesday taking its cluster to about 170 cases. Its capital, Sydney, and surrounding regions remain in lockdown until 9 July.