The death toll in mainland China from the new coronavirus has surged to 811, the National Health Commission said on Sunday, as deaths in the country surpassed those recorded during the 2002-2003 severe acute respiratory syndrome (SARS) outbreak.

In China, a total of 37,198 infections have been confirmed, most of which are in Hubei province and its capital, Wuhan, where the virus originated.

A US citizen became the first foreigner to die of the illness in China on February 6, while two deaths have been recorded elsewhere - one in Hong Kong and one in the Philippines. A Japanese man suspected of having the virus also died in China on February 8.

At least 25 countries have confirmed cases and several nations have evacuated their citizens from Hubei. Major airlines have suspended flights to and from China in an attempt to stop the spread.

WHO chief Tedros Adhanom Ghebreyesus has announced the departure of the advanced team for a WHO-led international expert mission to China to investigate the coronavirus.

The team is led by Dr Bruce Aylward, a "veteran of past public health emergencies," Tedros said in a tweet.