Acting Chief Medical Officer Paul Kelly says granting emergency use of the Pfizer vaccine - like regulators have in the US, UK and Canada - is not necessary locally.

"We don't need any vaccine this year," Prof Kelly told reporters in Canberra on Saturday.

"Other countries are in far different state than us and they should be prioritised."

Australia will wait for national regulator the Therapeutic Goods Administration to run through its own approvals of the Pfizer vaccine with the expectation it will be distributed in early 2021.

He highlighted the nation's success at controlling virus transmission.

"Today is eighth day in a row we've not had any community transmission," Prof Kelly said.

"That's the first time we've been able to say that since February."

This is compared with the fact that Friday was the most deadly day of the virus yet, with more than 13,000 deaths globally and skyrocketing infections, Prof Kelly said.

The emphasis right now is on having an impenetrable hotel quarantine system.

"Whilst we're concentrated on bringing Australians home ... we have to make sure absolutely that our hotel quarantine system is the very best it can be," Prof Kelly said.

He said he had "all confidence" in the Victorian contact tracing system now it had been revamped and international flights had resumed since Monday.

Victoria ended its 42-day virus-free streak on Saturday as five international arrivals in hotel quarantine tested positive.

Other states are handling more active cases than Victoria in quarantine, with eight fresh infections recorded across NSW, Queensland and Western Australia in the past 24 hours.

Prof Kelly said the Pfizer vaccine had reported excellent interim results in the New England Journal of Medicine, showing 95 per cent effectiveness in people of all ages, healthy or chronically ill.

It had a strong safety profile but the TGA would still go through its own process, he said.

Australia has pre-purchased 10 million doses of the Pfizer vaccine, while an extra 20 million of the AstraZeneca vaccine and a further 11 million of Novavax have been ordered to boost supplies after the University of Queensland-CSL's vaccine effort was abandoned.

Labor's Mark Butler said on Saturday that world's best practice was to invest in five or six vaccines.

"With the loss of the University of Queensland option which has not been shown to be safe and effective, we are now down to three," he said.

"We support the Australian government's venture with those three vaccines but we encourage them to do more."

Meanwhile, five former prime ministers have offered to be among the first to be vaccinated against the virus when the time comes, to encourage the public to take it.

Prof Kelly expressed doubt as to whether they would be first in line for the jab.

The priority groups will be people at high risk of infection, those at high risk of exposure and front line health workers, he said.

Australian Associated Press