Health authorities in New South Wales are investigating four possible cases of the deadly coronavirus.
NSW Health says it will not be disclosing the hospital locations of patients under investigation for privacy reasons.
It has not been revealed if the patients were on a flight which arrived in Sydney yesterday from the Chinese city of Wuhan.
"We will update the public immediately of any confirmed cases and need to disclose a person's movements," a statement read.
The death toll in China has risen to 25 and nearly 850 cases of patients infected with the virus are globally confirmed.
The virus originated in Wuhan, which has since been placed in lockdown.
The virus has already spread to other Chinese cities, while abroad, Thailand has confirmed four cases, South Korea and Japan have two cases each while the United States, Singapore and Taiwan have each reported one.
A flight from Wuhan arrived in Sydney yesterday and passengers were screened individually for symptoms of the highly contagious bug.
Australian authorities took no chances when China Eastern flight 749 from Wuhan touched down, stationing biosecurity officers and border security staff at the terminal to interview passengers.
Sydney is the only Australian city with direct flights to Wuhan.
The services, which were launched in 2017, run three times a week.
The University of Queensland (UQ) is confident it can develop a vaccine for the potentially deadly coronavirus in as few as 16 weeks as four people in NSW and two people in Brisbane are monitored for the virus.
Researchers from the university have been funded by an international organisation to use new rapid medical development technology to help create a vaccine for the new virus strain.