Chinese Premier Li Keqiang visited the central city of Wuhan, the epicenter of the outbreak, as the government sought to signal it was responding seriously to the crisis.
The total number of confirmed cases in China rose about 30% to 2,744, about half of them in Hubei province, whose capital is Wuhan.
As worries grew around the world, Chinese-ruled Hong Kong, which has had eight confirmed cases, banned entry to people who had visited Hubei in the past 14 days. The ban did not cover Hong Kong residents.
The number of deaths from the flu-like virus in Hubei climbed to 76 from 56, health officials said, with five deaths elsewhere in China, including the southern island province of Hainan, which reported its first fatality on Monday.
While a small number of cases have been confirmed in more than 10 countries, linked to people who traveled from Wuhan, no deaths have been reported elsewhere.
Li is the most senior leader to visit Wuhan since the outbreak began. Clad in a blue protective suit and mask, he inspected efforts to contain the epidemic and spoke to patients and medical staff, the government said.
The government is extending the week-long Lunar New Year holiday by three days to February 2, in a bid to slow the spread of the virus. The Lunar New Year is usually a time for millions of people to travel, but many have had to cancel their plans because of travel curbs over the virus.
Wuhan is already in virtual lockdown and severe limits on movement are in place in several other Chinese cities.
The city of 11 million clamped down further on Monday, announcing the suspension of visa and passport services until January 30.
Despite the curbs, the mayor of Wuhan said on Sunday that five million people had left the city for holidays and other reasons.
Images from Wuhan showing hospital corridors packed with people seeking treatment have circulated on social media, along with complaints of soaring prices for essentials such as vegetables.