High immunisation rates of children suggest Australians more broadly will be keen to take their COVID-19 jab when it becomes available.

Treasurer Josh Frydenberg insists Australia is still on track to receive the Pfizer COVID-19 vaccine from February, as new figures suggest people are more than happy to get their jab.

The Therapeutic Goods Administration is due to approve the Pfizer vaccine, and others Australia has signed up to, in the coming weeks.

"We are not about to cut corners," Mr Frydenberg told reporters in Melbourne on Sunday.

He said Australia is not in the same position as the US and UK where there are tens of thousands of cases each day with many lives lost.

"We have the virus under control here in Australia," the treasurer said.

"But we do want to roll out the vaccine, that's why the TGA's is going through its normal processes and we are still on track to receive this Pfizer vaccine, mid to late February."

There were no new locally acquired COVID-19 cases recorded across Australia on Sunday, while four new infections were reported in hotel quarantine in NSW and Victoria.

Health Minister Greg Hunt believes new immunisation figures show Australians have faith in the TGA to provide expert advice and ensure the safety and efficacy of all vaccines provided to the community.

Immunisation rates for five-year-olds are now beyond the aspirational target of 95 per cent coverage, reaching 95.09 per cent in the December quarter of 2020 and exceeding the World Health Organisation estimated international average of 86 per cent.

"Reaching our target of 95 per cent supports herd immunity to stop the spread of vaccine-preventable diseases," Mr Hunt said in a statement on Sunday.

"These figures show Australians have both the capacity and the will to lead the world in taking up COVID-19 vaccines, as they recognise how important vaccination is, and how it protects and saves lives."

Aboriginal and Torres Strait Islander children at five years old have the highest rates of immunisation in the country at 97.25 per cent.

At the same time, Australia's seasonal influenza vaccination program continues to provide increasing numbers of vaccines to Australians of all ages.

Meanwhile, Victorian authorities on Sunday said there were no new cases linked to Australian Open tennis quarantine and that one case has now been reclassified, meaning there are now nine positive cases rather than 10.

In Victoria more broadly there was just one new case, a man in his 40s who is in hotel quarantine.

Victorian health authorities asked people to stay sensible and celebrate Australia Day in a COVID-safe way.

"The movement of people is a main driver for the spread of COVID-19 and this virus can spread quickly, so we urge the people of Victoria to use common sense this Australia Day," they said.

There were no new locally acquired COVID-19 cases in South Australia and NSW, but three were recorded in NSW hotel quarantine.

Even so, the NSW health department reiterated testing rates are too low.

It said sewage testing detected coronavirus fragments at Warriewood on the northern beaches and North Head, which takes in Manly. Recent sewage testing has also uncovered coronavirus fragments at Liverpool.

"High testing rates are necessary to give confidence that no cases are going undetected in the community," Dr Christine Selvey said.