The man in his 70s was tested after developing "very mild" symptoms. He self-quarantined after arriving in Australia and a small number of people he was in contact with have gone into isolation.

The case takes the total in the state to 439, with two active cases.

"I reassure you that we don’t have any new cases of community transmission," said chief public health officer Prof Nicola Spurrier.

In total, Australia has had 6,875 cases of the virus, and 97 deaths. It and New Zealand, which has also managed to control its outbreak, are planning a quarantine-free "travel bubble" between them.