Queensland has recorded two new local cases of COVID-19 with a lockdown still set to end on Friday night.
Millions of people in southeast Queensland, Townsville, Magnetic Island and Palm Island are in lockdown on Thursday amid four separate virus outbreaks, including three involving the more contagious Delta strain.
Premier Annastacia Palaszczuk says one of the new cases is linked to the Portuguese club cluster, while the other is a Qatar Airways check-in desk worker at Brisbane Airport.
The discovery of two new local cases, after more than 28,000, tests, is encouraging news for Queenslanders hoping the lockdown will end at 6pm on Friday, as originally scheduled.
"We've still got another 24 hours to go to see what happens over the next 24 hours, and we'll update you tomorrow in relation to whether or not we can leave that lockdown," the premier said.
"But like I said, it is very very encouraging us, at this stage."
Chief Health Officer Jeannette Young said the Qatar Airways worker had been symptomatic since Sunday, meaning she'd been infectious in the community since last Friday.
The 30-year-old woman lives with another person, who is also being tested.
The worker also visited an Officeworks in North Lakes and a Coles supermarket at Murrumba Downs.
Dr Young said the woman likely contracted the virus at the airport, where she was checking in passengers while being exposed to flight crew members.
"We don't always know which of them are positive, which is why I really and truly insist people must wear masks at the international airport, and our domestic airports, that is really critical," she said.
Health Minister Yvette D'Ath has appointed a private doctor to lead a probe into why a 19-year-old clerical worker, who caught the Delta strain while working outside a COVID-19 ward, wasn't vaccinated.
Mater Health Infectious Diseases Physician Paul Griffin will look into what happened at the Prince Charles Hospital, she said.
The government has also written to five major hospitals to ask why vaccinations shouldn't be expanded to staff working near, but not within, COVID-19 facilities.
"Every time we have had transmission we have looked at how we can improve our processes," Ms D'Ath said.
"Every jurisdiction has done this, that has had an outbreak, whether in hotel quarantine or in our hospital system, to learn the lessons of what we can do better, but also to look at the changing nature of these variants and the risk profile."
The lockdown covers residents of Brisbane, Ipswich, Logan City, Moreton Bay, Redlands, Sunshine Coast, Noosa, Somerset, Lockyer Valley, the Scenic Rim, the Gold Coast, Townsville, Magnetic Island and nearby Palm Island until 6pm on Friday.
Residents in those areas are only be allowed to leave home to shop for essential items, exercise, to do essential work if they can't do so from home, to receive medical care or to give compassionate care.
