Queenslanders are breathing a sigh of relief, with the sunshine state recording no new COVID-19 cases and again dodging a lockdown.
Deputy Premier Steven Miles confirmed Queensland reported no new infections on Sunday, after detecting five new cases on Saturday.
The state government opted not to go into lockdown but flagged "very quick, fast action" may be needed if it saw seeding outside an infected family.
"I know the last 24 hours Queenslanders have had their fingers and toes crossed, and it's fantastic to bring news that we can breathe a sigh of relief," he told reporters on Sunday.
"There's no new cases in Queensland in the last 24 hours. This is the best result we could have hoped for.
"We're not out of the woods yet. We do need to continue to monitor the situation, particularly south of the river down through Logan and into the Gold Coast."
The outbreak has infected five members of the same family who live across two households, including a 13-year-old schoolgirl from Sunnybank.
The children were exposed to a visitor when they saw their father on Father's Day, then returned to their mother's home.
The man, who entered Queensland with two others on September 5, has since returned to NSW.
All three men are believed to have crossed the border with the correct passes but police are investigating.
Of the trio, two have since tested positive and Queensland Chief Health Officer Jeannette Young is now confident they are the source of the cluster.
"There's been minimal exposure from those two people, but people just need to be cautious," Dr Young said.
"We know that the person who did infect the 13-year-old girl had very little contact."
One of the men visited places in the Gold Coast area, prompting authorities to ask anyone with symptoms to come forward for testing.
There were more than 12,000 people tested on Saturday, while about 18,000 Queenslanders also got a COVID-19 vaccine dose.
It comes as the Queensland government announced a vaccine mandate for all hospital workers and ambulance staff.
Health Minister Yvette D'Ath said every worker must have had their first dose by the end of September and be fully vaccinated by the end of October.
"I know that's only three weeks away. But we're confident we can get there because the majority of our workforce is already vaccinated," she said.
Some 89 per cent of the state's staff in COVID-19 hospitals are already fully vaccinated, along with more than 80 per cent in general hospitals.
Ms D'Ath said the mandate had the support of unions, and the government would find alternative arrangements for staff who cannot or will not get vaccinated.
"For some of them, because they are working in really critical roles, they will be required to undertake further testing and another level of PPE," she said.
She wants to avoid the widespread transmission and deaths seen in the under pressure NSW hospital system.
"We're seeing too many deaths and too many infections in NSW not to do this," Ms D'Ath said.