A new local COVID-19 case has been recorded in South Australia, a man aged in his 20s linked to the Modbury cluster.
The young man had been isolating at home after a member of his family contracted the virus on July 20.
He has been transferred to a dedicated COVID-19 quarantine health facility along with three members of his household, who will now need to re-start their 14 days of mandatory quarantine.
LIVE UPDATES: South Australians in Queensland urged to return home
Premier Steven Marshall said the prolonged time between his family member's positive test and his own – about 12 to 13 days – was "a good demonstration of how this virus can be quite different in different people".
As the whole household had been isolating, he said there was "no reason to expect that there has been any exposure" in the wider community.
"The fact that they were in quarantine is a massive relief in South Australia," he said.
READ MORE: South Australians in Queensland urged to return, as restrictions loosen
The new case brings the total number connected to the Modbury cluster to 22.
It had been six days since the last two cases connected to the cluster were revealed, with the state marking one week since its COVID-19 lockdown has lifted.
The premier also expressed growing concern about the Delta outbreak in Queensland, with a new case outside of the locked-down south-east recorded today.
He called on all South Australians still in Queensland to consider returning home, saying it was "very possible" border restrictions will be tightened further if the outbreak continues to grow.
"We really want people from South Australia to get back into our state, because we are very concerned about that situation," Chief Public Health Officer Professor Nicola Spurrier said.
Currently, South Australians can return from the 11 hotspot Queensland local government areas, but they must isolate at home for 14 days.
Those returning from outside those areas don't need to quarantine but must undergo testing on days one, five and 13.