Eighteen people have been tested for coronavirus in NSW, 10 in Queensland, four in South Australia and one in Tasmania.
The death toll in China has reached 41, with more than 1300 cases confirmed.
Prime Minister Scott Morrison urged Australians not to panic and said the federal government was “taking this issue incredibly seriously” and had “activated the necessary precautions and procedures”.
Federal Health Minister Greg Hunt said Victorian and Commonwealth authorities would undertake “contact tracing” for passengers who had travelled on the January 19 Wuhan to Melbourne via Guanghzhou flight and would provide them with “information and advice”.
It comes as NSW Health confirmed three cases” of the deadly coronavirus – with another four people undergoing tests. Test results for the two NSW men suspected of having the virus will be confirmed late Saturday afternoon.
Authorities in China have put 14 cities in lockdown, closed parts of the Great Wall of China and Disneyland in Shanghai.
Victorian Health Minister Jenny Mikakos announced on Saturday a Chinese national aged in his 50s, had tested positive for the novel coronavirus in Melbourne after spending two weeks in Wuhan, the epicentre of the outbreak.
He is being treated at Monash Medical Centre in Clayton after arriving in Melbourne at 9am on January 19 on China Southern Airlines flight CZ321 from Guangzhou.
He displayed no symptoms on the flight to Melbourne, Ms Mikakos said.
Authorities warn it is “highly likely” there will be other cases of the deadly virus in Australia and it is still possible more passengers on the man’s flight will be diagnosed with coronavirus.
Mr Morrison noted that all flights out of Hubei province had been halted by the Chinese government.
Mr Hunt said the government was prepared to deal with the spread of the virus.
“Australia has world-class health systems with processes for the identification and treatment of cases, including isolation facilities in each state and territory,” Mr Hunt said.
“Our laboratories have developed testing processes for this novel coronavirus that can provide a level of certainty within a day.”
Yesterday the Department of Foreign Affairs and Trade raised the level of travel advice for Wuhan and Hubei Province in China to ‘level 4 – do not travel’ and issued a Smartraveller bulletin on the virus outbreak. The advice level for China as a whole has not changed.
Chief Medical Officer Brendan Murphy said it was important for people who had recently arrived in Australia from Wuhan, and those in close contact with them, to watch for signs of the coronavirus.
“We don’t know exactly how long symptoms take to show after a person has been infected, but there is an incubation period and some patients will have very mild symptoms,” Professor Murphy said.
“Symptoms include fever, cough, sore throat, vomiting and difficulty breathing. Difficulty breathing is a sign of possible pneumonia and requires immediate medical attention.
“People who arrive in Australia from an international flight with these symptoms should alert their airline, or a biosecurity officer if they have disembarked.”
Professor Murphy said it was not unexpected that the coronavirus would make it to Australia “given the number of cases that have been found outside of China and the significant traffic from Wuhan City”.
“There are other cases being tested each day, many of them are negative, but I wouldn’t be surprised if we had further confirmed cases,” he said.
Victoria’s deputy chief health officer Angie Bone said she was concerned that the infected man had visited a GP the day before presenting in hospital, but the doctor did not suspect the man had coronavirus despite him being a Chinese national and resident of Wuhan.
The man was confirmed as having coronavirus at 2.15am on Saturday.
Dr Bone said the man never went to the Huanan seafood wholesale market in Wuhan where the virus is thought to have originated.
“He’s potentially a second-hand case,” Dr Bone said, adding that little was known about the incubation periods of the virus so it was unclear where he contracted it.
NSW Chief Health Officer Kerry Chant confirmed all people tested for coronavirus in NSW had recently travelled to China.
She described it as a continually “revolving number,” and said some people in NSW had already been cleared of the virus, before others came forward to be tested.
“The fact is we are continuing to identify cases that meet the case definition,” she said. “We still don’t understand the transmissibility of this virus, but the evidence is that patient to patient transmission has occurred in Wuhan.”
Ms Mikakos said there was no cause for alarm for the community, and the patient in Victoria was isolated.
She said the risk of transmission remained low. Victorian and Commonwealth officials would be stationed at Melbourne Airport and a hotline would be set up for people to get information about coronavirus.
“This is an evolving situation. We are now one of 11 countries who have confirmed cases,” Ms Mikakos said.
“I do want to stress there is no reason for alarm in the general community. We have had flu pandemic and other situations in the past, including SARs, our system is geared up well to respond to these situations.”
The Melbourne patient has pneumonia and is in a stable condition, she said. Hospital staff treating him are wearing masks, gloves, and gowns while treating the man in an isolated room in the Monash Medical Centre.
Ms Mikakos stressed the man had spent his time since arrival with relatives at their home. He did not visit any public places, authorities said.
Dr Bone said anyone travelling to and from China should already be on high alert for the virus, adding that the man had shown no symptoms on the flight.
She said while authorities are not certain how infectious the virus was “it was quite possible” those who had contracted the coronavirus only become infectious once their symptoms appear.
Victorians and visitors returning from Wuhan City or other locations cases have been detected and being urged to closely monitor their health.
Professor Murphy said the Victorian government had acted swiftly and appropriately.
“Victoria has followed its strict protocols, including isolating the affected person,” he said. “I understand the patient has pneumonia and is in a stable condition.”
France has confirmed three cases of coronavirus marking the first confirmed diagnoses in Europe, while two cases have been confirmed in the United States.
Australian authorities are encouraging anyone who recently visited China and suspects they have the virus to ring ahead before presenting to their GP or emergency departments. They also urged them to make their travel history clear to medical staff.
Melissa Cunningham is The Age’s health reporter.
Dana is health and industrial relations reporter for The Sydney Morning Herald and The Age.