Two elderly Queenslanders are "not out of the woods" after being given overdoses of the coronavirus vaccine at an aged-care home.
Investigations are under way after the only two residents to receive shots at Brisbane's Holy Spirit Nursing Home on Tuesday were given four times the correct dose.
The pair - an 88-year-old man in hospital and a 94-year-old woman who remains at the home - have so far not shown any adverse reactions but they are being closely monitored.
"They are not out of the woods in that sense and so we are very concerned for their welfare," said Lincoln Hopper, the CEO of home operator St Vincent's Care Services.
A GP employed by third-party vaccination provider Healthcare Australia has resigned after administering the overdoses.
A nurse who worked out what was happening intervened and prevented any further incorrect shots being given.
Mr Hopper said vaccinations are continuing at St Vincent's Care Services homes.
But the group is carrying out on-site checks to ensure people working for companies trusted by the federal government to deliver vaccines have completed the mandatory training.
He said confidence in the vaccination program "has not been rocked" but there must be no repeat of what happened on Tuesday.
"That error has been so severe that we are reporting that GP to the health authorities. The regulator will need to understand what happened and what caused the error but it is distressing to us, our residents and their families."
The Queensland premier has sought urgent assurances from Prime Minister Scott Morrison that his plans for aged-care and broader community vaccinations are safe.
"None of this is good enough and the federal government must explain itself," Annastacia Palaszczuk told parliament on Wednesday.
She will ask the prime minister to convene a national cabinet meeting as soon as possible, saying public trust in the vaccination rollout is on the line.
"I want to know what training is being provided to people the federal government is employing to administer the vaccine in our aged-care facilities. I want to know about the communications strategies for the next phases of the rollout.
"People need and must have full confidence in this vaccine."
Healthcare workers are meant to complete online training modules before being able to administer the coronavirus vaccines, which come in multi-dose vials.
Health Minister Greg Hunt could not say if the doctor had completed the training.
"We will leave that to the investigation as to whether or not they either did not understand or did not complete (the training) - but it was a very serious breach in terms of following the protocol," he told reporters in Canberra.
"There has to be proof of participation and completion."