Testing isn’t important only because it helps track the pandemic. For hospitals, coronavirus tests are a crucial tool in managing scarce resources. If a patient comes in with COVID-19-like symptoms, doctors and nurses must act as if the patient has the virus. They must don personal protective equipment, or PPE, every time they interact with the patient until he or she tests negative for the coronavirus. Because the majority of tests still come back negative in most places, hospitals wind up burning through their supply of PPE while taking care of patients who do not actually have the coronavirus. There is a national shortage of PPE, and some places in California, including Los Angeles County, have already used up their emergency supply.

“Lab turnaround time is PPE,” says Geoff Baird, the acting laboratory-medicine chair at the University of Washington. “More than a day is a tragedy. Three to five is okay for outpatients if they can sit at home, but it doesn’t address the problem in a hospital.”

One physician at a community hospital in California, who requested anonymity to protect her job, echoed the sentiment that waiting on negative results hurts her ability to provide care. “Time to negative result for a mildly ill patient is maybe the most worrisome thing right now,” she told us, because it is creating “the bottleneck which will result in denial of care to patients we can save.”

At the same time, patients who do have COVID-19 also suffer from testing delays, because they cannot access all possible treatments, Greene said. “If you’re intubated, in critical care, and even your spouse has tested positive, if you don’t have a positive result, they can’t give you the experimental drugs,” she said.

A Quest spokesperson, Wendy Bost, told us that the company’s initial effort in California had been overwhelmed by demand. “There was a tremendous demand because we only had the one laboratory [in San Juan Capistrano] for about a week or more, and all the demand was being funneled into that laboratory,” she said. She claimed that the situation has improved for current testing. “The average turnaround time nationally is four to five days, from the time where we collect the specimen to when we report the results out,” Bost said. “However, there have been cases that have been several days longer than that.”

Quest did not disclose how many pending tests it has at the San Juan Capistrano facility or in California or in the nation.

Quest faces two major problems in dealing with its backlog, whatever its size. First, on March 9, Quest started using a labor-intensive, laboratory-developed test, Bost said. Then, sometime after March 13, it switched to using a highly automated, high-throughput test created by the Swiss manufacturer Roche.* The problem is that specimens collected for the first type of test cannot be used in the new machinery—and many of the early samples were meant for the laboratory-developed test. It does not matter how many high-speed Roche machines Quest is using now: They cannot be brought to bear on those other samples. This could be one reason for the existing backlog, though Bost told us she could not say so for sure.