More on the coronavirus.

As the U.S. battles to limit the spread of the highly contagious new coronavirus, the number of health care workers ordered to self-quarantine because of potential exposure to an infected patient is rising at an exponential pace. In Vacaville alone, one case — the first documented instance of community transmission in the U.S. — left more than 200 hospital workers under quarantine and unable to work for weeks.

Across California, dozens more health care workers have been ordered home because of possible contagion in response to a rapidly growing number of confirmed cases. In Kirkland, Wash., more than a quarter of the city’s Fire Department was quarantined after exposure to a handful of infected patients at the Life Care Center nursing home.

With the number of confirmed COVID-19 cases mushrooming by the day, a quarantine response of this magnitude would quickly leave the health care system short-staffed and overwhelmed. The situation has prompted debate in the health care community about just what standards medical facilities should use before ordering workers quarantined — and what safety protocols need to become commonplace in clinics and emergency rooms.

Dr. Jennifer Nuzzo, a senior scholar at the Johns Hopkins Center for Health Security, is among those arguing hospitals need to change course.

“It’s just not sustainable to think that every time a health care worker is exposed they have to be quarantined for 14 days. We’d run out of health care workers,” Nuzzo said. Anyone showing signs of infection should stay home, she added, but providers who may have been exposed but are not symptomatic should not necessarily be excluded from work.

The correct response, she and others said, comes down to a careful balance of the evolving science with the need to maintain a functioning health care system.

While hospitals are supposed to be prepared for just such a situation, Nuzzo said, their plans often fall short. “Absent any imminent public health crisis, it may not be one of their priorities,” she said. From 2003 to 2019, federal funding for the Hospital Preparedness Program in the U.S. was cut almost in half.

In Northern California, potential exposure to the new coronavirus was exacerbated because hospitals were caught unaware by the community spread of the virus and hampered by federal protocols that initially limited diagnostic testing to patients with a history of travel to a country where the virus was known to be circulating or contact with a person with a known infection.

“At the very beginning (of an outbreak) this will happen because you don’t know patients are infected and you only realize later that people were exposed,” said Grzegorz Rempala, a mathematician at the College of Public Health at Ohio State University who models the spread of infectious diseases.

Now that the disease has started to spread through the community, any patient with respiratory symptoms potentially could be infected, though health officials note the likelihood remains low. As providers start routinely wearing protective gear and employing strict safety protocols, accidental exposure should decline.