Health officials are urging Australians not to become complacent about coronavirus as social and business restrictions are stripped away.
Australia has gone 24 hours without a single case of community transmission but Acting Chief Medical Officer Paul Kelly warned the threat remained.
England has joined France and Germany in reintroducing nationwide lockdowns and the United States is recording 100,000 new infections each day.
"We haven't beaten it yet," Professor Kelly told ABC radio on Monday.
"We need to absolutely keep our eye on the ball. There is a global pandemic going on and those disturbing numbers from many of our friends overseas give us food for thought."
Professor Kelly said complacency was one of the major risks going forward.
"We need to remember this virus hasn't gone away," he said.
"There was and continues to be an increase in cases coming into our quarantine hotels."
Victoria has recorded three straight days of no new coronavirus cases, its best numbers in five months.
Now all states and territories have brought coronavirus under control, Prime Minister Scott Morrison wants all internal borders reopened by Christmas.
"I'm very hopeful it will be reached and certainly the prime minister is very keen for that to happen," Professor Kelly said.
"I'm sure all Australians are if it can be done safely, but those internal border measures are really decisions for the states."
Meanwhile, Health Minister Greg Hunt says Australia is close to securing two more sources for a coronavirus vaccine, which he expects will start rolling out in 2021.
So far, the government has two coronavirus vaccine contracts in place.
One is with the University of Oxford and AstraZeneca and the other is with the University of Queensland and CSL.
"The results from both of those have actually been positive, more positive than we had expected," Mr Hunt told reporters.
"We are now close to additional contracts and there are two further ones on the advice of the medical expert panel which are being pursued and which I am confident will be completed within the coming weeks if not earlier."
He wants all Australians who are willing to be vaccinated to receive their jabs within the next 12 months.
Australian Associated Press
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