The World Health Organisation made the announcement after an emergency summit as cases globally, including nine in Australia, rise.
The World Health Organisation has declared the coronavirus outbreak a public health emergency as cases of the disease rise overseas.
Director-General of the organisation, Dr Tedros Adhanom Ghebreyesus, said the declaration was made because of the spread of the virus.
"The main reason for this declaration is not because of what is happening in China, but because of what is happening in other countries," he said after an emergency meeting in Geneva.
"Our greatest concern is the potential for the virus to spread to countries with weaker health systems, and which are ill-prepared to deal with it."
Infections from coronavirus have spread from China to more than 8100 people globally, surpassing the SARS epidemic's total.
A ninth person has been diagnosed with the deadly coronavirus in Australia, with four cases in NSW, three in Victoria and two in Queensland.
It comes as passengers who shared a Melbourne-Gold Coast flight on Monday are at risk of having contracted the coronavirus from a fellow passenger with the disease.
Tigerair provide passenger details to health authorities
Passengers on a Tiger Air flight on Monday are being contacted by the state government over fears they may have contracted the deadly coronavirus.
Two Chinese nationals now confirmed to be infected with the virus were on board Tiger Air flight TT566 from Melbourne to the Gold Coast on Monday.
They were part of a tour group who had come from the Chinese city of Wuhan.
Queensland Health confirmed the state's second case of coronavirus infection late on Thursday as a 42-year-old woman.
The government is now attempting to make contact with the 171 passengers aboard Monday evening's flight.https://twitter.com/TigerairAU/status/1222744226762350593?ref_src=twsrc%5Etfw
She said anyone who spent two hours or more exposed to an infectious person in a confined space could be at risk. The flight time from Melbourne to the Gold Coast is about two hours.
The development came as Queensland Health Minister Steven Miles approved a public health emergency order giving authorities the power to detain suspected coronavirus victims.
Under the order Dr Young can give written orders telling people to stay at a particular place, and authorities can use reasonable force on those who don't comply.
Queensland Premier Annastacia Palaszczuk and senior ministers opted not to travel to a Labor caucus meeting in the Gold Coast hinterland so they could manage the health situation.
A total of 41 people across Queensland were tested for coronavirus on Thursday.
Third coronavirus case confirmed in Victoria
Victoria's health department is gathering information on possible coronavirus public exposure sites after a third case surfaced.
A Chinese woman in her 40s has been confirmed as the third Victorian case of the deadly virus on Thursday evening.
The woman has been isolated in the Royal Melbourne Hospital, with eight other people awaiting results of their coronavirus tests in Victoria.
The visitor from Hubei province is in stable condition and two close contacts are being monitored for symptoms.
Two new cases of coronavirus infection confirmed on Thursday evening - this new case in Victoria and another in Queensland - brought the total number of cases in Australia to nine.
The health department is yet to confirm the woman's location and movements before she was referred to hospital.
It has been revealed that a man in his 60s, who was confirmed as having the virus on Wednesday, had dinner with his family on Australia Day at The House Of Delight restaurant in Glen Waverley.
Victoria's Chief Health Officer Dr Brett Sutton has urged anyone at the restaurant between 5.30pm and 7pm on January 26 to be watch for symptoms.
Although Dr Sutton said the restaurant was allowed to open, a sign outside the establishment says it will remain closed until February 9, "in order to minimise the risk of the Novel Coronavirus".
The man became infected while travelling in China's Hubei province. His five relatives were put in isolation with him, and four of them were yet to receive results of their tests.
As of Thursday evening, tests have so far cleared up to 71 people of the virus in Victoria.
China coronavirus cases surpass SARS
The number of coronavirus patients has now surpassed the amount of people infected by Severe Acute Respiratory Syndrome in 2002 and 2003.
The vast majority of patients are in China where the virus originated in an illegal wildlife market in Wuhan and has gone on to claim 170 lives, latest official data showed.
But more than 100 cases have emerged in other countries, from Japan to the US, spurring anti-China sentiment and a wave of mask-buying.
South Korean firm Kukje Pharma is considering doubling or tripling shifts to cope with a rush of orders for "tens of millions" of masks.
"There's only so much we can do," an official at the firm said on Thursday.
Chris Weston, head of research at Melbourne brokerage Pepperstone, said an emergency declaration by the WHO could alarm investors.
"The fear is that they (the WHO) might raise the alarm bells ... so people are taking money off the table," he said.
The 2002-2003 Severe Acute Respiratory Syndrome also came from China, killing about 800 people and costing the global economy an estimated A$49 billion.
Economists fear the impact could be bigger this time as China now accounts for a larger share of the world economy.
One government analyst has forecast the crisis would lop a percentage point off China's first-quarter growth.
Global stocks tumbled on Thursday, while the yuan hit its lowest this year and oil prices slid.
Almost all the deaths have been in Hubei province - of which Wuhan is the capital - where 60 million people are living under virtual lockdown.
One of 60 Myanmar students trapped in Wuhan said most of the shops there were closed.
"We cannot go out and buy food," Si Thu Tun told online news outlet the Democratic Voice of Burma.
"Honestly, I have one big potato and three packs of instant noodles and some rice," he said.
Myanmar plans a special flight to get the students out within three days.
Australia, South Korea, Singapore, New Zealand and Indonesia were quarantining evacuees for at least two weeks, though the US and Japan planned shorter, voluntary isolation.
Three Japanese, from 206 evacuated on Wednesday, were infected, and two of them had not shown symptoms.
India was the latest nation to report a case, a student of Wuhan University. Meanwhile South Koreans protested at facilities earmarked as quarantine centres, throwing eggs at a minister.
South Korean President Moon Jae-in called for co-operation as the country prepared to evacuate the first of about 700 citizens from Wuhan.
The impact of the crisis even reached an Italian cruise ship, whose 6000 passengers were kept on board while tests were held on two Chinese travellers.
Source: 9News https://www.9news.com.au/world/coronavirus-australia-ninth-person-diagnosed-as-virus-surpasses-sars/98ecfbe1-91e1-4427-83dd-740cbcf56dd2