How Much Should the Public Know About Who Has the Coronavirus?

“We are right now learning and trying to project what is happening here in the United States almost entirely based on observations from these other countries,” Prof. Lewnard said.

Moritz Kraemer, a scholar at Oxford University who is leading a team of researchers in mapping the global spread of the coronavirus, says China’s data “provided incredible detail,” including a patient’s age, sex, travel history and history of chronic disease, as well as where the case was reported, and the dates of the onset of symptoms, hospitalization and confirmation of infection.

The United States, he said, “has been slow in collecting data in a systematic way.”

Dr. C. Jason Wang, a researcher at Stanford University, who has studied how Taiwan handled the coronavirus outbreak, says some of the measures taken in Taiwan would most likely not be accepted in the United States given privacy concerns. The government, for example, merged the airport immigration database with the national medical database so that doctors could immediately see if a patient had traveled out of the country.

But Dr. Wang says the proactive approach that Taiwan took to the virus, including aggressive tracing of cases, has helped keep the total number of confirmed infections — 283 on Saturday — much lower than experts initially expected. By comparison, the borough of Queens in New York City, with one-tenth the population of Taiwan, has 10,000 cases.

Some of the information being released to the public in Taiwan and Singapore would most likely be uncontroversial in the United States, he said. Taiwanese authorities, for example, have pointed out linkages between anonymized cases, including family clusters, in an effort to warn the public how easily the virus is transmitted within households.

Prof. Caplan of the N.Y.U. School of Medicine says it is paradoxical that the United States is providing less precise information to its citizens on the outbreak than Singapore, which puts limits on the spread of information through internet controls.

“Here we expect to get information so we have our choices and we make our decisions,” he said. “Our notion is information is the oxygen for democracy. Wouldn’t we want to receive more information than them?”