“Of course I’m nervous about getting infected,” said Cai Yi, head of the division of pain management at Wuhan Central Hospital, the same hospital where Dr. Li had worked. “But if we let ourselves be nervous, then what would happen to the people?”

China’s president and Communist Party leader, Xi Jinping, has praised hospital workers in Hubei as heroes, and mobilized the country in a “people’s war” against the coronavirus. But hospital workers in Wuhan said they often felt frustrated and alone.

Some have scrambled to buy protective gear with their own money, begged from friends, or relied on donations from other parts of China and abroad. Others have avoided eating and drinking for long stretches because going to the toilet meant discarding safety gowns that they would not be able to replace. Younger staff are assigned to the more critical cases, with the expectation that if they get sick they would be more likely to recover.

Even as Chinese officials disclosed how many medical workers had been sickened and killed by the virus, key questions remain, experts said, including how the workers became infected and whether the rate of transmission was slowing. Such omissions could make it more difficult for other countries to assess and reduce their own risks.

“Clearly it would have been useful for other parts of China who are beginning to struggle with this outbreak as well for the rest of the world to have these types of data as soon as possible,” said Malik Peiris, a virologist at the University of Hong Kong.

Dr. Tedros Adhanom Ghebreyesus, director-general of the World Health Organization, said it is seeking more information about the time period and circumstances surrounding the infections of health care workers.