When employees of Massachusetts biotech company Biogen were informed in late February that several among them had been diagnosed with COVID-19 after a company-wide meeting, they immediately went to hospitals for testing, but were turned away. Because of the scarce number of tests available in the U.S., doctors, upon the advice of the Centers for Disease Control (CDC), were following strict protocols for who could be tested: people who had symptoms and had traveled to a country where cases were endemic, or had been in close contact with someone who had tested positive. Most of the Biogen employees didn’t have any of the symptoms of fever, cough or difficult breathing that are the hallmarks of COVID-19, but understandably wanted to know if they had been exposed.

Two weeks after the meeting, 77 of Massachusetts’ 95 confirmed cases are Biogen employees.

The criteria for who can be tested have since been relaxed, and doctors can now order the test for any patient, using their best judgement on whether it’s necessary. Still, testing in the US lags far behind that in other countries, due to a combination of technical and policy issues, as well as political pressure.

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When the first cases of COVID-19 were reported in the US, two labs at the CDC were the only ones permitted to conduct COVID-19 testing, using a test developed by the agency’s own researchers. When the CDC tried to expand testing by providing its test kits to state and local public health labs, there were problems with the initial version of the kits, which the CDC then reworked.

That delay, along with the growing number of undetected cases in the U.S., prompted the Food and Drug Administration (FDA) on Feb. 29 to expand its approval criteria to allow any qualified lab to develop its own test. Two of the largest diagnostic commercial labs, Quest Diagnostics and LabCorp, have begun testing this week but are still conducting only a few thousand a day as they scale up capacity.

“My people have been working all weekend, 24-7,” says Dr. Jon Cohen, CEO of BioReference Laboratories, which plans to roll out its test this week. “Within a week, if not sooner, we should be able to do 1,000 to 2,000 tests a day, and from there, scale up higher.” A spokesperson for North Carolina-based LabCorp says the company has been conducting several thousand tests a day since March 5, and plans to add staff and equipment to increase that number. Quest Diagnostics, based in New Jersey, says the company released its COVID-19 test on March 9, and plans to perform tens of thousands of tests a week within six weeks.

Taken together, that’s still a tiny fraction of the number that should be conducted in a country of 327 million people, say experts. As of March 11, CDC, state and public health labs have conducted more than 11,000 tests since mid-January. By comparison, South Korea has tested more than 200,000 of its population of 51 million since January.

In the US, rollout of widespread testing is plagued by not only logistical issues but political over-promising and supply constraints. When the FDA expanded its approval criteria at the end of February, agency commissioner Dr. Stephen Hahn predicted that the policy would lead to enough test kits for more than a million people within a week; when that goal wasn’t met, White House Coronavirus Task Force point person Mike Pence was forced to extend the target date by a week as companies scrambled to familiarize themselves with the test and order the chemicals and reagents they needed.

Even when tests are available, there’s the question of how and where people will take them. Because COVID-19 is proving highly contagious, doctors and hospitals are reluctant to encourage people with symptoms to come into offices to provide samples. Public health officials and lab companies are exploring new ways of running these tests, including at drive-through facilities, or separate tents that some hospitals are setting up outside of their emergency rooms, to minimize contact that potentially positive people would have with other patients.

There are also still technical hurdles for some of the labs that are trying to run the CDC test. Smaller labs, including those at major hospitals, are struggling to meet some of the FDA’s approval requirements. For example, the technicians need to show that they have the technical and chemical expertise to perform the test properly to get a valid result both on a large number of samples as well as a range of samples types, including the most difficult type to work with, sputum (the material from the lungs that is released when you cough). But, “the numbers of samples we need to validate is close to impossible for a single lab to have,” says Michael Mina, director of viral diagnostics at Brigham and Women’s Hospital.

Cohen notes that another challenge for some labs involves extracting the virus from the sample. The COVID-19 test actually picks up fragments of genetic material of SARS-CoV-2, the virus that causes the illness, in the form of RNA, so pulling the virus out of the sample is critical. “The kit that the CDC sends, for example, includes [testing chemicals] but what it doesn’t include is the extraction needed to pull out the viral RNA,” he says. “That’s a big lift for some labs to do.” Instead, they turn to other providers like Qiagen. But there is already a backlog, says Dr. Thomas Theuringer, spokesperson for the company. “This demand is challenging our capacity to supply certain RNA extraction kits used for SARS-CoV-2 related lab-based tests.” In response, the company has ramped up production at its manufacturing sites in Germany, Spain and the US to meet the surge in demand, but in the meanwhile, labs are looking for ways to avoid these supply chokepoints by coming up with other ways to handle the RNA extraction.

For Americans on the ground, this is all moving far too slowly.

Liz Satterfield was diagnosed with metastatic breast cancer in 2016. Despite the difficult prognosis for her disease, “I was beating the odds,” she says. “Then something like COVID-19 comes along.” Satterfield is currently on two different chemotherapy treatments, which can wipe out her immune system and make her susceptible to practically any infection circulating around her—including COVID-19.

To make matters worse, Satterfield and her partner live in Kirkland, Washington, which has among the largest clusters of COVID-19 infections in the country, and has recorded the highest death rate in the US from the disease. The couple and their two-year-old daughter live a mile from the long term care facility where nearly two dozen people have died of the disease.

“Not only am I a cancer patient, but I live in the epicenter of this outbreak,” she says. “Absolutely I want to get tested and I want my whole family tested. My wife is young and female, so she is in the category that she could likely be positive and display no symptoms. We’re also not seeing an explosion of cases among children, so my [two year old] daughter could also be in that category. They could be silent carriers.”

But when she saw her oncologist last week, Satterfield didn’t even bother asking for testing, because she knew that since she wasn’t showing symptoms, doctors wouldn’t likely prescribe a test. There just simply aren’t enough tests to go around, and that’s terrifying to Satterfield and millions of other Americans.

“The lack of testing availability up to now scares the crap out of me,” she says.

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