Australia's leading vaccine advisory group said the gap between the second and third vaccine dose would remain at five months for the time being.

However, the Australian Technical Advisory Group on Immunisation said there would be some flexibility for those who were close to the five-month period and looking to get their booster shot.

Chief medical officer Professor Paul Kelly said people would be able to get their booster shot one or two weeks early if they needed to.

"Because of this time of year, ATAGI is urging anyone giving vaccines to be flexible, given clinics may be closed or people may be travelling," Professor Kelly told reporters in Canberra.

"But mostly, the five months is the time (ATAGI) want to stress."

ATAGI continues to meet regularly to review the time frame for booster shots.

The chief medical officer said talks were also under way with overseas colleagues on the spread of the Omicron variant.

The new strain has led to an explosion of cases in several states, with NSW recording a pandemic-high daily case number of 2213, with one death.

While the rise in cases were not unexpected, Professor Kelly said Omicron had given an added complexity to the situation.

"There are some places that are seeing cases for the first time, locally transmitted. This is what we knew would happen," Professor Kelly said.

"There was an expectation that as we opened up as a society, became more attuned to living with COVID, that indeed we have to live with COVID."

Thursday saw a record number of booster shots administered across the country, with more than 135,000 third doses handed out.

The head of Australia's vaccine rollout Lieutenant General John Frewen said there were no concerns with vaccine supply issues.

"The amounts that we have available far exceed any demand right now, we have done forecasting work on exactly when boosters come due," he said.

"The big demand when large numbers of people become eligible for boosters is into the February and March period."

The change from a six-month wait to a five-month wait between the second dose and third dose has seen the number of people eligible for boosters rise from 1.7 million to four million people.

That figure is expected to jump further to seven million eligible by the end of January and 11 million by the end of February.

Thursday saw the national booster program tick over one million doses administered, as the overall national vaccine rate passed 90 per cent of over 16s.

Prime Minister Scott Morrison said the vaccination milestone was an incredible achievement.

"Thanks to the efforts of every single Australian, we are coming through COVID with one of the lowest fatality rates, strongest economies and now highest vaccination rates in the world," he said on Facebook.

There were eight new infections in the Northern Territory as Tennant Creek was forced into a lockdown just a week before Christmas.

Victoria registered 1510 new cases and seven deaths on Friday while the ACT had 20 new cases.

South Australia will ease restrictions further on December 28 despite recording 64 new cases.

Queensland Premier Annastacia Palaszczuk reintroduced a mask mandate for hospitals, retail, public transport and airports after the state recorded 16 new cases.

Australian Associated Press