Mr. Xi, already under scrutiny for the Chinese government’s slow and erratic response to the coronavirus outbreak, now faces pressure to quell anger among low-income families and dispel broader fears of an economic downturn. The party has long staked its legitimacy on the idea that it can deliver prosperity and protect the working class.

“The Chinese Communist Party leadership does not like to be criticized for neglecting or abandoning workers,” said Jane Duckett, the director of the Scottish Center for China Research at the University of Glasgow. “Their ideological underpinnings — Marxism-Leninism, socialism — lie in being a party of the ‘workers and peasants.’”

Ms. Duckett said the party was probably wary of discontent among workers. Mr. Xi has said that the government should watch employment closely and that companies should avoid large-scale layoffs.

The virus, which has killed at least 2,400 people and sickened nearly 77,000 in China alone, has brought parts of the Chinese economy, the world’s second largest, to a near standstill. While some factories have started up again in recent days, many are still closed or operating well below capacity, with parts in short supply and workers stranded hundreds of miles away.

Businesses across a variety of sectors — manufacturing, construction and transportation — have ordered their employees to stay home, usually without pay. That has created strains for many migrants, who earn barely enough to keep up with the rising cost of living in Chinese cities and often hold little in savings.

While wages are low, migrants can still earn more in the cities than they would in the countryside, where jobs are scarce. They are willing to go to cities for a shot at a better life, even if they must live in crowded workers’ dormitories or run-down apartments.