No new locally-acquired COVID-19 cases have been recorded in South Australia, Victoria or Western Australia as the country deals with widespread outbreaks.
SA reported five new local cases on Wednesday involving a miner who recently returned from the Northern Territory, his wife and three of their children, all aged under 10.
A further 28 miners who returned to the state from the same site last week have been retested and again produced negative results.
No new cases were detected from 11,700 tests on Wednesday after Premier Steven Marshall opted not to plunge the state into lockdown.
South Australian Premier Steven Marshall says he is relieved the state has recorded no new coronavirus cases. Source: AAP
"It's a huge relief for every single person in this state," the premier told reporters on Thursday.
"We're very pleased with the way things are going at the moment."
Victoria also reported a clean COVID sheet on Thursday, with no local or overseas cases detected among just over 29,000 tests.
The state's COVID commander Jeroen Weimar said local active cases in the state have fallen to just eight and there are fewer than 230 primary close contacts in isolation.
Two infected returned travellers are in hospital, as is an Arcare Maidstone aged care resident who continues to shed the virus.
In Western Australia, the four-day lockdown in Perth and the Peel region is on track to finish on schedule, with the state recording no new coronavirus cases on Thursday.
More than two million people are under lockdown until 12.01am on Saturday after local cases of the Delta variant were detected.
About 15,800 West Australians got swabbed on Wednesday, a result Premier Mark McGowan described as "amazingly encouraging" while urging further testing.
Locked down Darwinites out exercising along the foreshore at Nightcliff, in Darwin. Source: AAP
"It puts WA in the best possible position, especially as our contact tracers continue to find potential contacts," he told reporters on Thursday.
"When it comes time to lift restrictions we want to be confident this incredibly infectious virus, the Delta variant, is not still in the community.
"The next 24 hours are crucial ... we hope to have more to say about the next steps we are going to take tomorrow."
Masked members of the public are seen on St Georges Terrace in Perth. Source: AAP
The outbreak has been traced to a 51-year-old physiotherapist who recently returned to WA from NSW, where she contracted the Delta variant.
Infections were subsequently detected in two men aged in their 20s and 30s and a 32-year-old woman who attended various venues throughout Perth's northern suburbs.
Of 360 close contacts identified to date, 295 have so far tested negative, as have 1173 out of 2503 casual contacts.
