The number of people killed in China by the coronavirus has risen to 81, with almost 3,000 confirmed ill.
The national new year holiday has been extended by three days to Sunday, in an attempt to contain the spread.
On Monday, Chinese Premier Li Keqiang visited Wuhan, the capital of Hubei province and centre of the outbreak.
The number of deaths in Hubei province has climbed from 56 to 76, with five deaths elsewhere.
Wuhan is in lockdown and several other cities have imposed travel bans.
In Shanghai, the government has stopped businesses from returning to work until 10 February.
The ban applies to all companies apart from utilities, medical firms, medical suppliers, and supermarkets.
Meanwhile, the director-general of the World Health Organization, Tedros Adhanom Ghebreyesus, is in Beijing to discuss the outbreak with the Chinese government and health experts.
The BBC’s Robin Brant in Shanghai says extending the main holiday of the year is a highly unusual move.
But after the pre-new year travel surge, the prospect of half a billion people getting back on trains, planes and buses and criss-crossing the country again is the last thing the government wants, he adds.
At least 44 cases have been confirmed abroad, including in Thailand, the United States, and Australia.
There have been no deaths outside China.
The coronavirus causes severe acute respiratory infection and there is no specific cure or vaccine.
Most of the deaths have been of elderly people or those with pre-existing respiratory problems.