WUHAN, China — The rapid spread of a deadly virus across China caused growing global alarm on Monday, with Germany advising citizens to avoid the country, Mongolia closing its border and other nations racing to evacuate citizens trapped at the epicenter of the epidemic.

The coronavirus has now killed 81 people and infected more than 2,700 across China, with cases found in around a dozen countries as far away as France and the United States.

In a sign of the mounting official concern, Premier Li Keqiang visited ground-zero to oversee containment efforts in Wuhan, a city of 11 million people where the disease emerged late last month.

The government has sealed off Wuhan and other cities in Hubei province, effectively trapping tens of millions of people, including thousands of foreigners, in a bid to quarantine the virus that struck amid the Lunar New Year holiday.

The Communist government decided to extend the holiday, initially due to end on Jan. 30, for three days to limit population flows and control the epidemic.

Twenty-four new deaths were confirmed in Hubei on Monday, and the southern island province of Hainan reported its first fatality, bringing the nationwide toll to 81.

More than 700 new infections were confirmed, while the number of suspected cases doubled over 24 hours to nearly 6,000.

The youngest infected patient was a nine-month-old baby being treated in Beijing.

In Wuhan, reporters saw construction workers making progress in the construction of one of two field hospitals that China is racing to complete by next week to relieve overcrowded hospitals swamped with people waiting hours to see doctors.

On day five under quarantine, residents shouted "Go Wuhan" from their windows, according to videos posted online, and journalists saw a building lighting up the words in red in front of the Yangtze river in the evening.

"I'm getting more concerned everyday," Do Quang Duy, 32, a Vietnamese masters student in Wuhan, said.

Landlocked Mongolia, which is heavily dependent on trade with China, closed the border with its huge neighbor to cars.

Schools and universities will be shut until March 2, while public gatherings involving sports and entertainment are also suspended, Vice Prime Minister Enkhtuvshin Ulziisaikhan said.

Malaysia banned visitors from Wuhan and its surrounding Hubei province.

In Germany, Foreign Minister Heiko Maas said the government was holding crisis talks with health experts to discuss the spread of the virus.

"Travellers should consider delaying or cancelling any unnecessary trips to China," Maas said.

The US, France and Japan are among countries looking to evacuate their citizens from Wuhan.

A US-bound flight is scheduled to leave Wuhan on Tuesday with consular staff and some American citizens. France plans to fly citizens out of the city in the middle of this week.

Belgium, Bangladesh, India and Spain said they were working to repatriate their nationals, while Germany was considering the possibility.

World Health Organization chief Tedros Adhanom Ghebreyesus headed to Beijing for discussions with Chinese officials.

But the WHO last week stopped short of declaring the outbreak a global emergency, which could have prompted international trade or travel restrictions.

The world body on Monday said the global risk from the deadly virus in China was "high", admitting an error in its previous reports that said it was "moderate".

Global stock markets and oil prices plunged Monday over coronavirus fears.

The virus is believed to have jumped to people from animals in a Wuhan market that sold a wide range of exotic wild game.

China on Sunday banned all wildlife trade until the emergency passes.

The virus has caused global concern because of its similarity to Severe Acute Respiratory Syndrome (SARS), which killed hundreds across mainland China and Hong Kong in 2002-2003 and was also traced to the wild game trade.

Authorities around China have already imposed aggressive curbs on transport during the usually high-traffic new year season to keep the virus out.

At Beijing's main international airport, almost all passengers wear masks. Fever checks are conducted at subway and railway stations.

Typically, hundreds of millions of people crisscross China in jam-packed buses and trains during the holiday, a time for family reunions.

But the festivities have been ruined this year by coronavirus, which can be transmitted between humans, with people told to avoid gatherings.

Countless popular public attractions and seasonal festivals have been shut down. Several Beijing malls shortened their opening hours, according to state media.

The nationwide measures threaten to put a dent on an economy that was already slowing down.

Beijing and Shanghai were among places mandating stringent checks and 14-day observation periods for people arriving from Hubei.

Wuhan's mayor Zhou Xianwang said around five million people had left the stricken city during the new year travel rush in January, highlighting fears the virus could spread further.

"(Shanghai's) biggest risk is still imported risk," Gu Honghui, a top official in the city government, told reporters. — AFP