Greater Brisbane's lockdown could still end before the Easter holidays after just two new coronavirus cases emerged in the community.
The cases were reported after 33,408 tests were conducted in the 24 hours to 9am on Wednesday.
One is a nurse from Brisbane's Princess Alexandra Hospital, who had received her first vaccine dose, and the other is her housemate.
Another case of community transmission linked to one of two Brisbane clusters was also reported in the northern NSW town of Byron Bay on Wednesday.
The two new cases in Queensland take the total number of community infections to 17, along with two COVID-19 patients who initially spread the virus to hospital workers.
Premier Annastacia Palaszczuk says a decision on extending the Greater Brisbane lockdown, which is due to end at 5pm on Thursday, will be made in the next 24 hours.
"The fact we do not have any unlinked community transmission in the southeast or in our state is absolutely encouraging," she told reporters.
"Fingers crossed all will be looking good for Easter.
"If we see very good testing rates across Queensland and we don't see any unlinked community transmission, the signs for Easter are looking positive."
Infectious COVID-19 cases have visited venues in Greater Brisbane, the Gold Coast, Gladstone, Toowoomba, Hervey Bay and Gin Gin.
Most cases are now in Brisbane or regional hospitals, including on the Gold Coast, at Toowoomba, and Bundaberg.
Chief Health Officer Jeannette Young said 1700 people were self-quarantining and getting tested after possibly coming into contact with known cases.
Health Minister Yvette D'Ath is also self-isolating after she woke up with a sore throat and flu-like symptoms, and decided to get a COVID-19 test. She lives in the Moreton Bay region, which has a number of exposure sites.
"I immediately got a COVID test this morning and am isolating until I get a negative result," Ms D'Ath posted on Twitter.
"This is the right thing to do. Everyone is reminded to get a COVID test if you have any symptoms, regardless of how mild."
The number of exposure sites in Queensland jumped beyond 100 overnight, with the NSW government issuing alerts for a number of venues in Byron Bay and Ballina.
Brisbane's Princess Alexandra Hospital, where two nurses and a doctor have tested positive, was locked down even harder on Tuesday night.
Queensland's second-largest hospital started turning away all but the most critical patients on Wednesday morning. And, like all Brisbane hospitals, it had been turning away visitors since Friday.
The hospital is testing staff who've worked in its coronavirus ward, 5D.
Any staff member who set foot inside that ward between March 23 and 26 has also been ordered to enter 14 days of quarantine, from their last entry.
Senior hospital managers have been asked to help identify those staff, with the quarantine directive expected to affect large numbers of workers and disrupt clinical services.
Opposition Leader David Crisafulli said the government must offer businesses and tourism operators immediate grants, tax waivers and mental health support to cope with lockdown.
He said the announcement about extending the Greater Brisbane lockdown, and restrictions across Queensland, should happen as soon as possible on Thursday.
"Minutes matter, and if an announcement can be made at 7am tomorrow, please make the announcement at 7am," Mr Crisafulli said.
"Don't wait until later in the morning. That's how critical it is."