BEIJING—China on Wednesday reported another drop in the number of new cases of a viral infection and 97 more deaths, pushing the total dead past 1,100 even as the country remains largely closed down to prevent the spread of the disease.

The National Health Commission on Wednesday said 2,015 new cases had been reported over the last 24 hours, declining for a second day. The total number of cases in mainland China is 44,653, although many experts say a large number of others infected have gone uncounted.

The 97 additional deaths from the virus raised the mainland toll to 1,113.

Despite the official end of the extended Lunar New Year holiday, China remained mostly closed for business as many remained at home, with some 60 million people under virtual quarantine.

The World Health Organization has named the disease caused by the virus as COVID-19, avoiding any animal or geographic designation to avoid stigmatization and to show the disease comes from a new coronavirus discovered in 2019.

The illness was first reported in December and connected to a food market in the central Chinese city of Wuhan, where the outbreak has largely been concentrated.

China's official media reported Tuesday that the top health officials in Hubei province, of which Wuhan is the capital, have been relieved of their duties. No reasons were given, although the province's initial response was deemed slow and ineffective. Speculation that higher-level officials could be sacked has simmered, but doing so could spark political infighting and be a tacit admission of responsibility.

The virus outbreak has become the latest political challenge for the party and its leader, Xi Jinping, who despite accruing more political power than any Chinese leader since Mao Zedong, has struggled to handle crises on multiple fronts. These include a sharply slowing domestic economy, the trade war with the U.S. and push-back on China's increasingly aggressive foreign policies.

Zhong Nanshan, a leading Chinese epidemiologist, said that while the virus outbreak in China may peak this month, the situation at the center of the crisis remains more challenging.

“We still need more time of hard working in Wuhan,” he said, describing the isolation of infected patients there a priorityon.

“We have to stop more people from being infected,” he said. “The problem of human to human transmission has not yet been resolved.”

Without enough facilities to handle the number of cases, Wuhan has been building prefabricated hospitals and converting a gym and other large spaces to house patients and try to isolate them from others.

The restart of business poses a risk of further spreading the virus, but China has little recourse, said Cong Liang, secretary general of the National Development and Reform Commission, the country's main economic planning body.

“Without the reopening of businesses, in the short term, it will affect the supply of medical material and ... in the long run, it will affect the supply of all kinds of production and life materials and will make the control and prevention efforts on the front line unsustainable. The target of defeating the epidemic will not be reached,” Cong said at a news conference.

In Hong Kong, authorities evacuated part of an apartment block after cases among its residents raised suspicion the virus may be spreading through the building's plumbing. Three residents in one apartment were confirmed to have the virus days after a resident who lives 10 floors above them.

During the 2002-03 outbreak of SARS, an illness caused by a related virus, a number of infections in Hong Kong were linked to one building's sewage pipes.

Hong Kong has confirmed 49 cases in the current outbreak.

Postal operators in the United States, China, Singapore and elsewhere said the suspension of flights to slow the virus spread was having a major impact on the global flow of letters and parcels.

The United States Postal Service informed its counterparts around the world on Tuesday that it was “experiencing significant difficulties” in dispatching letters, parcels and express mail to China, including Hong Kong and Macau, because airlines have suspended flights to those destinations.

It said the USPS said can no longer accept items destined for China “until sufficient transport capacity becomes available.”

The Universal Postal Union, a U.N. agency for postal cooperation between its 192 member countries, said the flight suspensions would impact mail delivery “for the foreseeable future.”

The Chinese mail service, China Post, said it was disinfecting postal offices, processing centers and vehicles to ensure the virus doesn't spread via the mail and to protect postal staff.

The virus does “not survive for long on objects. It is therefore safe to receive postal items from China," China Post said.