Two more Queenslanders have been diagnosed with COVID-19 and more than 200 hospital staff are in quarantine as the corrective services cluster grows.
A nurse working with infected patients at Ipswich Hospital tested positive for the virus, Chief Health Officer Jeannette Young says.
The other case is the sister of a student at Staines Memorial College, who was already in quarantine.
"We (also) have 222 staff at the Ipswich hospital in quarantine," Dr Young told reporters on Sunday.
"That means there is some pressure on the capacity of the hospital."
She said both new cases had links to outbreaks in the Brisbane Youth Detention Centre and Queensland Corrective Services training centre.
"In one it is a household contact situation ... The second case is one of the nurses who has been looking after one of those known cases," she said.
"All of our cases are most likely - I don't have proof - linked to one of the three young women who went down to Melbourne," Dr Young added, referring to the female trio who allegedly lied on their border declarations after a shopping and party trip to Victoria in July.
Two of them then spent more than a week in the Brisbane area visiting restaurants, cafes and working before testing positive to coronavirus.
Dr Young reminded Moreton Bay islands residents to get tested if they develop virus symptoms after a Russell Island woman tested positive on Saturday.
The woman, who commuted on a local ferry while infectious, is also part of the corrective services cluster that has now grown to 83 cases.
"I want to commend her for her response," Dr Young said.
"She has, after hearing all of the messages about if you can't social distance wear a mask, been doing that."
Deputy Premier Steven Miles meanwhile launched a broadside aroundCOVID-19 at the opposition ahead of next months' election.
"I am disappointed the LNP was breaking the rules on the day that there was a positive case confirmed in the community," he said of Saturday's confirmed case.
Dr Miles also called out LNP frontbencher John-Paul Langbroek for urging Queensland's borders to be reopened.
He said opposition leader Deb Frecklington "should have the guts to sack him from the front bench".
There are currently 25 active COVID-19 cases in Queensland.