To help cope with the volume, the Trump administration asked companies like Quest to prioritize processing tests for hospitalized patients and health-care workers with symptoms.

Hospitals are starting to make similar moves. In New York City, the U.S. epicenter with more than 23,000 confirmed cases, limited testing supplies and high demand drove a major hospital system on Thursday to say it will only test hospitalized patients and people in the emergency department, according to an email seen by Bloomberg News. That’s in keeping with the recommendations of the New York City health department, which in its March 20 statement added that “testing may play a more significant role after the pandemic has peaked.”

The Centers for Disease Control and Prevention’s most recent national guidance is similar, though it makes allowances for a doctor’s judgment and notes state and local governments may adapt “to respond to rapidly changing local circumstances.”

At New Jersey’s largest hospital system, RWJBarnabas Health, Chief Medical and Quality Officer John Bonamo says wait times for results have stretched from about 48 hours to as long as 10 days. That means more hospital beds are being used and workers have to use more personal protective equipment, or PPE, when treating them.

“We’re using up large amounts of PPE because we can’t get tests back,” Bonamo says. “What’s happened is the volume has grown to the point that the results have gotten exponentially slower.”

At Hackensack Meridian Health, which has 17 hospitals in New Jersey, results are taking three to five days. That’s “completely unacceptable,” said Daniel Varga, chief physician executive.

Quest began telling hospitals and other Covid-19 test clients this week to stick orange cards in bags with specimens deemed high-priority under the new guidelines.

“The orange cards are Quest’s way of operationalizing it,” Samuels said. “If someone’s in the hospital, it can’t wait.”

Jon Cohen, a physician and executive chairman of commercial tester BioReference Laboratories, says that in the absence of clear guidelines, the company has given top priority to hospitalized patients since it began Covid-19 testing two weeks ago, also using labeling to sort them.

“As a doctor, I know that testing patients is a big deal,” he said. “They require lots of therapy and attention from front-line workers.”