Wednesday marks the final day of a door-to-door campaign in Wuhan, the central Chinese city where the virus emerged, to root out anyone with symptoms whom authorities may have missed so far.
"This must be taken seriously," said Wang Zhonglin, Wuhan's newly minted Communist Party secretary.
"There's nothing more important than human life," Wang said in remarks published by the government of Hubei province, where Wuhan is located. "If a single new case is found (after Wednesday), the district leaders will be held responsible."
Mainland China has reported a total of 74,185 cases of the new form of coronavirus and 2,004 deaths. New cases have fallen to under 2,000 for the past two days, but officials and analysts have warned that the threat of a more serious outbreak remains as workers gradually return to work following a prolonged Lunar New Year holiday.
In Hong Kong, a spokesman for Princess Margaret Hospital reported the city's second death out of 62 cases. Media reported the victim was a 70-year-old man with underlying illnesses.
"Prevention and control work is at a critical time," Chinese President Xi Jinping said during a phone call Tuesday evening with British Prime Minister Boris Johnson, according to Chinese state media.
Likewise, U.N. Secretary-General Antonio Guterres told The Associated Press in an interview in Lahore, Pakistan, that the virus outbreak "is not out of control, but it is a very dangerous situation." He said that "the risks are enormous and we need to be prepared worldwide for that."
The much-criticized quarantine of a cruise ship in Japan ends later Wednesday. The Diamond Princess' 542 virus cases were the most in any place outside of China, and medical experts have called its quarantine a failure.
The passengers from the MS Westerdam, another cruise ship, who remain in Cambodia have tested negative for the virus, Cambodia's Health Ministry announced Wednesday.
One of the almost 700 passengers who had already left Cambodia after the ship docked last week was found to have the virus when she was tested after arriving in Kuala Lumpur, Malaysia. The discovery that the 83-year-old American woman harbored the virus caused the suspension of plans to send home the other passengers still in Cambodia.
The dispersal of the others who also departed Cambodia to various countries has caused concern that they might be undetected carriers of the virus, and health authorities in several countries were tracing them to take protective measures.
The Westerdam was allowed to dock in Cambodia after Japan, Taiwan, the Philippines, Guam and Thailand refused to let it land because of fear that its passengers might spread the virus.
China has locked down several cities in the hardest-hit province of Hubei, halting nearly all transportation and movement except for the quarantine efforts, medical care and delivery of food and basic necessities.
The country also may postpone its biggest political meeting of the year, the annual congress due to start in March, to avoid having people travel to Beijing while the virus is still spreading. One of the automotive industry's biggest events, China's biannual auto show, was postponed, and many sports and entertainment events have been delayed or canceled.
Many countries have also set up border screenings and airlines canceled flights to and from China to prevent further spread of the disease, which has been detected in around two dozen countries and caused almost 1,000 confirmed cases outside mainland China. Five deaths have been reported outside the mainland, in Hong Kong, Taiwan, Japan, the Philippines and France.
South Korea evacuated six South Koreans and a Japanese family member from the ship, and they began an additional 14-day quarantine Wednesday. More than 300 American passengers were evacuated earlier and are quarantined in the United States, including at least 14 who had tested positive for the virus.
On Tuesday, the U.S. government said the more than 100 American passengers who stayed on the ship or were hospitalized in Japan would have to wait for another two weeks before they could return to the U.S.
The U.S. also upgraded its travel advisory for China to Level 4, telling its citizens not to travel to anywhere in the country and advising those currently in China to attempt to depart by commercial means.
"In the event that the situation further deteriorates, the ability of the U.S. Embassy and Consulates to provide assistance to U.S. nationals within China may be limited. The United States is not offering chartered evacuation flights from China," the notice said.
"We strongly urge U.S. citizens remaining in China to stay home as much as possible and limit contact with others, including large gatherings. Consider stocking up on food and other supplies to limit movement outside the home," the notice said. The U.S. previously flew out scores of its citizens on charter flights from Wuhan but does not have any further plans to do so, it said.
Despite such warnings, Beijing was showing signs of coming back to life this week, with road traffic at around a quarter of usual, up from virtually nothing a week ago. While most restaurants, stores and office buildings remained closed, others had reopened. People entering were required to have their temperatures taken and register their contact information.