Queensland has recorded four new COVID-19 cases overnight, with three acquired locally and one recorded from an overseas traveller.
All three new cases were close contacts of seperate clusters and are considered 'low risk'.
One is the brother of the woman who worked at Prince Charles Hospital, who has been diagnosed with highly contagious Delta strain of the virus and triggered the state's latest snap lockdown.
Another case was linked to the Brisbane Portuguese restaurant cluster, that person has been in hotel quarantine for the entirety of their infectious period.
The third case was a crew member with a positive Virgin flight attendant, authorities are now investigating if they were in the community while infectious before entering quarantine.
There were 18,447 tests completed overnight and a record breaking 16,963 vaccines administered.
Premier Annastacia Palaszczuk said this is "good news" and that contact tracers have been afforded time to get on top of the outbreak.
"It's wonderful to see people doing the right thing, so I thank everyone sincerely," she said.
"Our mission over the next three days is to do that contact tracing and make sure that we have everyone who is a close contact."
Under the current lockdown residents in Greater Brisbane, Townsville, Gold Coast, Ipswich, Lockyer Valley, Scenic Rim, Magnetic Island and Palm Island and the Sunshine Coast must stay in their homes unless they're purchasing essentials items, are an essential worker, or seeking medical care.
Premier Palaszczuk urged everyone to keep there eye on the growing list of exposure sites and to come forward for testing at the first sign of any symptoms.
The Premier said that there will be a full investigation into why the medical worker who tested positive to the Delta strain while working at the Prince Charles Hospital in north Brisbane was not vaccinated.
"It wasn't a guideline, it wasn't a principle, it was a direction. So there will be a full investigation into that," she said.
"There will be a full and thorough investigation and someone will be held responsible.
'Running out' of vaccines
Queensland health minister Yvette D'Ath said the state has just eight days left of the in demand Pfizer vaccine.
Minister D'Ath said that the state government has had it's request for an extra 130 trays rejected by the Commonwealth and that the state is now at a "critical" low.
Queensland top health official Dr Jeanette Young has also criticised the federal government's decision to drop the age of AstraZeneca vaccine.
"I do not want under-40s to get AstraZeneca," Dr Young said.
Dr Young said that younger people are at risk of developing a rare "clotting" disease.
"They [young people] are at increased risk of getting the rare clotting syndrome," she said.
"We've seen up to 49 deaths in the UK from that syndrome. I don't want an 18-year-old in Queensland dying from a clotting illness who, if they got COVID probably wouldn't die."
