NSW has recorded 390 new community Covid-19 cases - a new daily infection record since the start of the latest outbreak.
Two more Covid-related deaths have also been reported - a woman in her 40s in southwestern Sydney who died in her home, and a man in his 90s in the Hunter, New England area. The woman wasn't vaccinated and the man was vaccinated but also under palliative care.
Of today's locally acquired cases, 140 are linked to a known case or cluster and the source of infection for 250 cases is under investigation.
Ninety-eight cases were in isolation throughout their infectious period and 43 were in isolation for part of their infectious period. Fifty-eight cases were infectious in the community. The isolation status of 191 remains under investigation.
It comes amid reports children are increasingly catching coronavirus in NSW as the state's Delta outbreak continues to spread.
Young children have accounted for almost 15 per cent of NSW's coronavirus infections in the past fortnight. Yesterday, 44 children under the age of nine tested positive.
Those aged 10 to 19 also accounted for 70 of NSW's 345 locally acquired cases yesterday. This means a third of yesterday's cases were people aged 19 and younger.
A silver lining in the worrying surge of infections among children is the fact that the majority don't contract serious disease.
As of Tuesday, 12 per cent of teenagers aged 16 to 19 in NSW had received their first dose of a Covid-19 vaccine, up from 7 per cent a week earlier, the Sydney Morning Herald reported.
With NSW's community case numbers continuing to climb and a snap lockdown in the ACT, there are fears a state-wide lockdown could be looming.
Greater Sydney and multiple regional Local Government Areas (LGAs) are living under strict lockdown conditions, including Armidale, Dubbo, the Newcastle and Hunter region, the Northern Rivers, Tamworth and parts of western NSW.
NSW Deputy Premier John Barilaro told radio station 2GB this morning that a state-wide lockdown could be on the cards if the virus spreads from the ACT to southern NSW.
"We do have a lockdown situation in Canberra now.
"That could become problematic for southern NSW; if that was to breach there then I would absolutely be saying maybe it is time for a state-wide lockdown."
Locked-down Victorians are in for more pain ahead, with stay-at-home orders set to continue well beyond next Thursday.
That's according to some of Australia's top health experts, who told the Herald Sun newspaper today that the lockdown was likely to be extended again, with restrictions set to remain in place for weeks - if not months - to come.
Victoria recorded 15 new community Covid-19 cases overnight. Of those cases, 11 are linked to known outbreaks and four are still being investigated. Only eight were in quarantine throughout their infectious periods, meaning seven were in the community while infectious.
The head of Melbourne University's School of Population and Global Health, Nancy Baxter, told the Herald Sun she thought it was "unlikely" restrictions would lift next week.
And when it comes to interstate travel, she said Victorians would be out of luck for months on end.
"For the next three or four months we just need to accept there's no guarantee for interstate travel and plans."
The ACT has recorded two new local cases of Covid-19 today after Canberra entered a snap seven-day lockdown yesterday afternoon.
The lockdown was triggered by the state's first confirmed Covid-19 case from an unknown source in more than a year. Three close contacts of the original case had since tested positive.
There is now a total of six active Covid-19 cases in Australia's capital.
For the next seven days, Canberrans are only allowed to leave their homes for essential reasons, including essential employment, healthcare, essential groceries and supplies and up to one hour of outdoor exercise.
Queensland has today recorded seven new locally acquired cases of Covid-19, all linked to the existing cluster and detected while in home isolation.
Thousands of Queenslanders are in isolation, but a large number of those will be released as the 14-day period since the beginning of the cluster ticks over.
The state's Delta outbreak - which originated at the Indooroopilly State School and has now reached 137 - has largely been contained, but Premier Annastacia Palaszczuk fears the NSW crisis could breach the border.
On Thursday the Premier told Queenslanders "do not go" to NSW as she again threatened to ramp up border closure restrictions.