hina has warned the ability of the coronavirus to spread is getting stronger as the death toll increased to 80 and the number of confirmed cases reached more than 2,700.
The authorities said little is known about the new virus, and they are unclear on the risks posed by it mutating.
National Health Commission Minister Ma Xiaowei said the incubation period for the coronavirus can range from one to 14 days, and it is infectious during this time.
This was not the case with the previous Severe Acute Respiratory Syndrome (SARS) outbreak, which also originated in China and killed nearly 800 people around the world in 2002 and 2003.
"According to recent clinical information, the virus' ability to spread seems to be getting somewhat stronger," Mr Ma told reporters.
In response to the mounting crisis, containment efforts - which to date have included travel restrictions and the cancellation of major events - are to be ramped up in China.
The Lunar New Year holiday has been extended by three days in an effort to contain the virus' spread
The US is also to evacuate its diplomatic staff from the central Chinese city of Wuhan in Hubei, the epicentre of the outbreak, and has offered a limited number of seats on the flight to its citizens at greater risk of coronavirus.
The UK Foreign Office has advised against "all travel to Wuhan" and said people should leave if they are able to do so.
The government is "looking at all options" to help stranded Britons, Home Secretary Priti Patel told Sky News.
More than 50 people have now been tested for coronavirus in the UK, but there are still no confirmed cases, according to the Department of Health (DoH).
France is also looking at repatriating around 800 of its nationals from Wuhan, the government has said.
China's National Health Commission said on Monday morning there were 769 new cases confirmed in the 24 hours through midnight on Sunday.
So far 80 people in China have died in the latest outbreak, which has spread to other parts of the country including Beijing and Shanghai, with confirmed cases reaching 2,744.
A small number of cases have also been confirmed in Thailand, Japan, South Korea, the US, Vietnam, Singapore, Malaysia, Nepal, France, Australia and Canada.
In Wuhan, where 11 million residents are already on lockdown, most vehicle use has been banned and 6,000 taxis have been earmarked to help transport people if needed.
The Chinese military has sent 450 medical staff, some with experience in past outbreaks including SARS and Ebola, to to help treat patients, while supplies, including 14,000 protective suits, are being rushed to the city.
Two new dedicated hospitals are also being built in the city to cope with rising numbers of cases.
Medical workers have been among those infected - and according to Wuhan media reports, a 62-year-old doctor has died from the virus.
Chinese President Xi Jinping has described the situation as "grave" and said the government was stepping up efforts to restrict travel and public gatherings.
The outbreak has overshadowed the start of the Lunar New Year, when hundreds of millions of Chinese travel at home and abroad to be with families, with public events cancelled and many tourist sites shut, including Beijing's Forbidden City and part of the Great Wall.
Cruise operators have also cancelled some sailings due to embark from Chinese ports.
The Chinese government has also extended the Lunar New Year holiday by three days to next Sunday in an effort to contain the spread of the virus.
Hong Kong, which has six confirmed cases, has declared a virus emergency, scrapped celebrations and halted direct transport links with Wuhan.
In Beijing, people have been urged not to shake hands but instead salute using a traditional cupped-hand gesture.
Canada has a "presumptive" confirmed case of the virus in a resident who had returned from Wuhan, while the US has registered four cases in Washington state, Chicago, Southern California and Arizona.
Australia, Japan and Malaysia have each declared four cases.
France reported Europe's first cases on Friday.
No deaths have been reported outside China.
Airports around the world have stepped up screening of passengers from China, although some health officials and experts have questioned the effectiveness of such screenings.
Doctors at a Paris hospital said two of the three Chinese nationals in France who have been diagnosed with the virus had arrived in the country without showing any symptoms.
A report by infectious disease specialists at Imperial College London on Saturday said the epidemic "represents a clear and ongoing global health threat".
It added: "It is uncertain at the current time whether it is possible to contain the continuing epidemic within China."
