The Chinese government has quarantined the city where the deadly coronavirus originated and plans to shut down the airport and public transport, according to reports on the country's social media networks.
China may have also drastically under reported the number of people infected by a mysterious coronavirus that has since spread around the world.
The number of deaths linked to the virus, that originated in China, has risen to 17 — a near doubling in the past 24 hours - according to officials in Hubei province. More than 500 people are infected.
But there are fears that figure could be as high as 10,000, with warnings the new strain is "as deadly as Spanish flu" which killed 50 million people.
Professor Neil Ferguson, an expert in mathematical biology at Imperial College London, said the death rate was "roughly the same as for The Spanish flu epidemic, at around one in 50".
The virus, which causes pneumonia-like symptoms, was discovered in the metropolis of Wuhan, the capital of Hubei, in late December.
Chinese officials had earlier counted 470 people infected across the country. But reporting by The Guardian suggests the true number may be as high as 1700.
Relatives told the publication that some Chinese hospitals are not testing patients for the virus.
A man named Huang alleges his mother was admitted to hospital with a fever and cough.
She was not tested for the mystery illness, nor quarantined from other patients.
She died on January 14 - with the official cause of death listed as severe pneumonia. Two doctors told the family privately that she had likely contracted the coronavirus, but provided no documentation.
The woman's family was allegedly pressured to cremate her body. Afterwards, staff disinfected the vehicle they had travelled in and threw away hazmat suits.
Incidents of the disease have also been reported in Japan, the Philippines, South Korea, Taiwan, Thailand and the US, as well as in the Chinese territories of Hong Kong and Macau.
There was one suspected case of the virus in Australia, with a man placed in isolation in Brisbane over fears he contracted it while in China. He has since been cleared and released from home isolation.
An Australian doctor ordered the tests when the man presented with flu-like symptoms after returning home from visiting the city of Wuhan.
He has since been released from isolation, with Queensland Health confirming he was no longer showing symptoms.
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Several countries increased border health checks to guard against the disease's spread, including Australia, the US, the UK and Russia.
The new coronavirus belongs to the same family of viruses that caused Severe Acute Respiratory Syndrome (SARS), a disease that killed 800 people globally in a 2002-03 pandemic that also started in China.
Scientists in China said the new coronavirus may have been transmitted during the illegal trade of wild animals.
China's Disease Control and Prevention Centre director Gao Fu said the virus is believed to have originated at a market in Wuhan, from where it mutated and became transmissible from person to person.
"From what we know, the source was the wild animals sold at the seafood market," Gao told journalists on Wednesday.
"The virus of this wild animal is gradually mutating."
NORTH KOREA BAN
North Korea has made the decision to ban foreign tourists from entering the country as a way of safeguarding against the spread of a deadly virus from China.
The announcement was made by leading operator, Young Pioneer Tours, with the company saying it had been informed North Korea was temporarily not allowing tourists due to the spread of the coronavirus, which has been named 2019-nCoV.
The mystery virus emerged in the city of Wuhan, China, and has so far killed at least nine people, with 440 confirmed cases and almost 1400 people under medical observation.
Most foreign tourists to North Korea are Chinese or people of other nationalities who travel to the North from China, its major diplomatic ally and biggest aid benefactor.