Queensland's move to ensure all healthcare workers with direct contact with COVID patients have at least their first dose of vaccine has been criticised as not coming soon enough.
Two separate clusters have been linked to a doctor and nurse at the Princess Alexandra Hospital, but Chief Health Officer Jeannette Young said the mandate could not have happened sooner because of the number of staff needed to respond to a rapid escalation in caseload.
"We didn't have enough vaccine, we had to roll the vaccine out," she said on Tuesday.
"It's just so unfortunate that this outbreak has occurred when it did. Another month and all of these staff would absolutely have been protected."
The number of COVID cases in the state's hospitals has increased from five to 78 in about five weeks, most of which were acquired overseas.
The state opposition supports the mandate but said it should have happened sooner, criticising the vaccine rollout as sluggish.
"As a nurse the last thing that I would be doing is putting my staff at risk and we need to make sure that they're all vaccinated. It's a sensible decision, it should have happened earlier," shadow health minister Ros Bates said.
"It stands to reason that maybe if these staff had been vaccinated (or) not been treating COVID-positive cases, then we might not be in a lockdown."
More than 41,000 frontline healthcare and hotel quarantine workers had received their first vaccine dose, representing 89 per cent of the workforce, Premier Annastacia Palaszczuk said on Tuesday.
"We expect that to be completed over the next 48 hours," she said.
The two distinct clusters linked to the doctor and nurse at the PA Hospital were confirmed on Tuesday.
"She has exactly the same genome ... to a gentleman who arrived and was treated in the PA hospital and was treated on the 22nd of March," Dr Young said of the nurse.
She had a shift on March 23, and Dr Young believes she acquired the infection at the hospital despite not working directly with COVID patients that night.
The nurse's sister has been infected with the same genome, as have five of the new cases confirmed overnight.
"All of our cases are linked to either the first cluster with that doctor who worked at the PA or this second cluster, which is a brand new cluster unrelated to that first cluster linked to the nurse," Dr Young said.
Three of the new cases are under investigation, one of which is a known contact of an existing case and the other two are believed to be linked to the first cluster.
Two cases were acquired overseas and detected in hotel quarantine.