People returning to Beijing from extended holidays have been ordered to undergo a 14-day self-quarantine to help prevent spread of the new coronavirus, while hard-hit Hubei province reported more than 2,400 new cases.

Key points: A shutdown on the scale of China's current response is unprecedented

A shutdown on the scale of China's current response is unprecedented Some economists are forecasting major economic consequences of the outbreak

Some economists are forecasting major economic consequences of the outbreak Chinese authorities expect that 160 million people will soon return to their home cities

State newspaper Beijing Daily said people failing to obey would be punished, but it was not immediately clear how that would be enforced or whether the restrictions would apply to non-residents of the Chinese capital or foreigners arriving from abroad.

"From now on, all those who have returned to Beijing should stay at home or submit to group observation for 14 days after arriving," read the notice from Beijing's virus prevention working group cited by the Beijing Daily.

"Those who refuse to accept home or centralised observation and other prevention and control measures will be held accountable under law."

The virus, also known as COVID-19, is killing about 2 per cent of those it infects, but is able to spread faster than other respiratory viruses that have emerged this century.

Hubei officials said there were 2,420 new cases on Friday and 139 more deaths.

Including the latest numbers from Hubei, the total number of cases in mainland China now exceeds 66,000, with more than 1,500 deaths.

The figures show no sign that the outbreak is nearing a peak, said Adam Kamradt-Scott, an infectious diseases expert at the Centre for International Security Studies at the University of Sydney.

Epidemic 'under control', assures Chinese official

Vehicles spraying disinfectant have been deployed across Chinese cities. ( Reuters via China Daily )

Around 500 million people in China are currently affected by policies put in place restricting movement, to contain COVID-19.

That's more than the entire population of the United States and is equivalent to roughly 6.5 per cent of the world's population.

As of Friday, at least 48 cities and four provinces in China have issued official notices for lockdown policies, with measures ranging from "closed-off management", where residents of a community have to be registered before they are allowed in or out, to restrictions that shut down highways, railways and public transport systems.

Beijing trains were almost empty on the first day "back to work" for China after the extended Lunar New Year holiday. ( ABC: Steve Wang )

Citizens cannot leave the cities of Wuhan, Huanggang, Ezhou and a few others in Hubei province, while Shanghai and Beijing have only put movement restrictions in place for some smaller communities such as building blocks or neighbourhoods.

Many cities have reduced public transport lines and routes, while a few have closed intra-city public transport entirely.

Altogether, 80.41 million people have been affected by shut bus or metro lines.

Transport restrictions and official advice to stay home has dissuaded many from travelling back to work. ( ABC: Steve Wang )

A top Chinese official acknowledged that coronavirus was a huge challenge, but defended Beijing's management of the outbreak and lashed out at the "overreaction" of some countries.

State Councillor Wang Yi, who also serves as China's foreign minister, said China has taken decisive measures to fight the epidemic, many going beyond international health regulations and World Health Organization (WHO) recommendations.

"Through our efforts, the epidemic is overall under control," he said.

Shutdown is having a major impact on the economy

Across Beijing and in cities around the nation, many small shops run by out-of-towners remain locked up. ( ABC: Steve Wang )

China is struggling to get the world's second-largest economy going after the annual Lunar New Year holiday, which was extended to prevent further contagion.

Cinemas, temples and other tourist sites were shut down to prevent crowds from forming. Group tours were cancelled and businesspeople told to put off travel.

President Xi Jinping warned top officials last week that efforts to contain the virus had gone too far and were threatening the economy, Reuters sources said.

A report published by the China Cuisine Association said scare over the epidemic has cost the catering sector 500 billion yuan in lost earnings during the week-long Lunar New Year holiday, with 93 per cent of restaurants shutting down operations.

Restaurants have struggled to cope with the impact of a virus that has infected tens of thousands of people worldwide and sent dozens of cities into lockdown. ( AP: Mark Schiefelbein )

But as some businesses reopen, Beijing has told anyone who still can work from home to stay there.

Amid these measures, canteen lunches have been banned in favour of boxed meals eaten at desks. Meetings are held online, not in person.

Employees must wear masks all day and report their temperature twice a day as fever is one of the virus' main symptoms.

Xu Yahua, an official from China's transport ministry, said the government expects 160 million people to start returning to their cities of residence next week.

Economists polled by Reuters said China's economic downturn would be short-lived if the outbreak was contained, but expected this quarter would show China's slowest growth rate since the global financial crisis.

The Chinese carmakers' association said auto sales in China were likely to slide more than 10 per cent in the first half of the year because of the epidemic.

Michael Pettis, a finance professor at Peking University, recently told the ABC that China's Government will likely nevertheless press on with a GDP target of 6 per cent.

"What we may see is GDP growth for the first quarter down substantially, but then in subsequent quarters they'll likely significantly increase spending," he said.

The death toll in mainland China has jumped by more than 100 in recent days. ( AP: Zhang Yuwei via Xinhua )

A WHO-led joint mission with China will start its outbreak investigation work this weekend, focusing on how the new coronavirus is spreading and its severity, WHO director Tedros Adhanom Ghebreyesus said.

The mission will also seek more details on how, where and when the more than 1,700 health workers infected contracted the new virus, WHO officials said.

Outside mainland China, there have been nearly 450 cases in some 24 countries and territories, and three deaths.

Japan confirmed its first coronavirus death on Thursday. One person has died in Hong Kong and one in the Philippines.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 57 seconds 57 s Authorities are apparently using drones to chastise residents

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