Health officials are pleased Victoria's coronavirus infections are not dramatically increasing but want to see them start to drop as the renewed lockdown has an effect.
Victoria recorded another 374 cases on Tuesday and three more people have died.
NSW confirmed 13 new cases, just one of whom is in hotel quarantine, while Tasmanian officials reported a woman in hotel quarantine after visiting Victoria tested positive.
Most of the NSW cases were linked to growing clusters at an outer Sydney restaurant and pub.
Victorian Premier Daniel Andrews is confident his state's strict lockdown measures are having a direct impact.
"At the end of the day, we're not seeing the (case numbers) doubling and doubling again," he told reporters.
Deputy Chief Medical Officer Michael Kidd said everyone had hoped there would be a drop in cases over the first few weeks, as with the earlier lockdown in March and April.
"We have got to wait and watch just for another few days to see what happens and see if we do actually turn down the curve with those numbers," he said in Canberra.
His colleague Nick Coatsworth warned people to change behaviour around social distancing, hygiene and testing or risk a Melbourne-style outbreak.
"If people don't get the message, they will find themselves in the situation that greater Melbourne and Mitchell Shire are in at the moment," he said.
But he said rising cases in NSW were still linked to known outbreaks, making it different to Victoria at this stage.
NSW Premier Gladys Berejikilian is urging people to wear masks in public in situations where it is difficult for people to keep their distance.
But she's stopped short of following the Victorian government which will make face coverings compulsory in Melbourne and Mitchell Shire from Thursday.
Prime Minister Scott Morrison outlined an extension of the JobKeeper and JobSeeker coronavirus support payments, the size of which will be reduced in coming months.
In the United Kingdom, Oxford University scientists working with pharmaceutical giant AstraZeneca say a trial shows the vaccine produces a protective immune response and appears to be safe.
Professor Kidd said the results were encouraging but was cautious in his optimism.
"There is still a long way to go with those trials to see if that response is maintained over an extended period of time, if the vaccines themselves are going to be safe to distribute widely through the population and whether the vaccines are going to be able to be mass-produced," he said in Canberra.
The vaccine is intended to induce antibody and T-cell responses so it can attack the virus and infected cells.
Expanded trials will aim to vaccinate 50,000 people over the next six to eight weeks.