A fifth person in Australia has potentially contracted the new coronavirus as the nation's Chief Medical Officer says more cases are "highly likely" to emerge.

Preliminary test results for one person being investigated by NSW Health have come back positive for the deadly coronavirus, with confirmation expected on Monday. Four other people tested negative.

Passengers arrive at Sydney Airport wearing masks. Credit:Janie Barrett

In Victoria, health authorities said 11 more people were waiting for test results, while in Queensland six people tested negative on Sunday afternoon.

A Chinese man in his 50s was the first person to test positive for the virus in Australia, and he remains in quarantine at the Monash Medical Centre in Melbourne.