America is finally starting to test for the coronavirus in significant volumes. On Thursday, the total number of coronavirus tests conducted in America topped 100,000, according to the COVID tracking project. That's a 10-fold increase from a week earlier. In the coming days, we can expect the pace of testing to continue increasing as more and more organizations—both academic labs and for-profit companies—ramp up testing efforts.

This is important because America has a lot of catching up to do. A series of early missteps at the federal level hampered America's testing efforts in the early weeks of the coronavirus crisis. It wasn't until the end of February that the Food and Drug Administration opened the door for a wide range of organizations to offer coronavirus tests.

In the last week, we've started to see the results of that change. Private companies are starting to ship hundreds of thousands of tests. Drive-through testing stations are sprouting up all over America.

But the explosion of new testing efforts will create challenges of its own. Josh Sharfstein, a professor at the Johns Hopkins University School of Public Health, argues that coordination will be increasingly important as the volume of testing increases. A Thursday story in The Wall Street Journal painted a picture of chaos as patients struggled to get tested—even after they've gotten a referral from a doctor to get a test. Some drive-through testing facilities have had long lines and unpredictable hours, the Journal reports.

To get maximum value out of all this testing, officials are going to need to rationalize and streamline these testing processes. Patients need predictable rules for when they are eligible to be tested and a predictable process for actually getting a test and getting results. And public health officials need standardized ways of gathering test results.

Some labs are also suffering from a shortage of supplies, Axios reports. As we detailed in our February explainer, testing for the virus behind COVID-19 is a multi-step process that involves a number of chemical reagents. These chemicals are mostly available off-the-shelf, but the system isn't designed to handle sudden, massive spikes in demand.

"We are keeping redundancy very much on the back of our minds," Harvard's Michael Mina told Axios. "There is a concern that some item might become out of stock and so as soon as we are live with our test, we will start validating other modifications."

We saw this first-hand. On Thursday, Ars Managing Editor Eric Bangeman drove to a drive-through testing site near his home in the Chicago area to get some photos for this story. On Friday, the hospital hosting those tests announced it was suspending its drive-through testing program due to a shortage of test kits.

Still, there's every reason to expect that testing providers will work out these kinks. The number of coronavirus tests soared this week, and we should expect that progress to continue in the coming weeks. And that's important because America is going to do a lot more testing to get the coronavirus outbreak under control.

Federal missteps meant America started out behind on testing

America started out behind on testing capacity due to a series of early mistakes by federal agencies. The story starts on January 31, when the secretary of Health and Human Services declared the novel coronavirus to be a public health emergency. Due to a quirk in federal law, this declaration meant that anyone wanting to test for the coronavirus first needed to seek approval from the Food and Drug Administration.

The FDA has a lot of discretion in how it uses that authority. The agency could have set up a streamlined process to allow a wide variety of organizations to create their own tests. But it didn't do that.

The Centers for Disease Control was working on a coronavirus test, and initially the FDA decided not to allow anyone else to develop tests of their own. Unfortunately, when the CDC sent out an early batch of coronavirus testing kits to state and local laboratories, many of the labs were unable to validate the results.

The CDC's efforts to troubleshoot this flaw wasted valuable time.With a limited number of tests available, the CDC initially limited testing to those who had recently traveled to coronavirus hotspots or those who had come into contact with a known coronavirus carrier. That made it difficult to track early cases of community spread within the US.

Coronavirus tests are growing exponentially

Finally, on February 29, the FDA opened the door to other labs developing their own tests. Under the FDA's new framework, labs that met certain prior regulatory requirements would be allowed to begin using their own tests before they had gotten explicit approval from the FDA. Under the new guidance, labs had a 15-day grace period after they began testing to file the necessary paperwork with the FDA.

"That changed everything," one lab director told the New Yorker. "We didn’t have to wait to get the forms in and then wait for the response.”

That decision opened the floodgates. In the last three weeks, the volume of coronavirus testing has grown exponentially. Data from the COVID Tracking Project shows that the total number of coronavirus tests performed in the US grew from fewer than 1,000 on March 4 to almost 10,000 by March 12 and more than 100,000 by March 19.

These numbers are still far from sufficient to get the coronavirus under control. South Korea, with about 15 percent of the US population, has tested 270,000 people. But America's testing capacity has been growing fast, and we can expect continued growth in the coming days and weeks.

On Wednesday, Abbott Labs announced FDA approval of its coronavirus test. The company said it was "deploying 150,000 laboratory tests immediately" and was aiming to reach a million tests a week before the end of March.

Another major medical testing provider, Roche, announced on Monday that it was planning to ship out 400,000 tests. "The test kits are being sent to a network of more than 30 hospital and reference laboratories in the US that already have the required instrumentation in place and have the ability to implement high-volume testing immediately."

These are just two of many examples of US providers working to ramp up coronavirus testing capacity. With their help, the US will soon have far more coronavirus testing capacity than it has today.

Why testing is important

Testing isn't only important because it helps individual patients understand their medical conditions and guide their treatment—though that's obviously important. In an epidemic, testing is also crucial to help public health officials effectively direct resources, get the spread of the virus under control, and ultimately enable people to return to normal lives.

Until recently, health care professionals and public health officials have been flying blind. They could only test a small fraction of the patients who exhibited coronavirus-like symptoms, and so they've tended to reserve tests for patients who exhibited severe, potentially life-threatening symptoms. Other patients are typically told to go home and self-isolate—without knowing for sure if they have the coronavirus.

That uncertainty makes it hard to take precautionary steps to prevent further spread of the virus. If a patient is able to confirm that they have the coronavirus, then they (or public health officials) can warn friends, family, and other close contacts about the potential infection. Ideally, those people can get tested as well. But without testing, public health officials don't know which cases to focus on.

And large-scale testing will ultimately allow public health efforts to become more targeted, allowing more Americans to return to normal lives. That won't happen immediately, Johns Hopkins expert Josh Sharfstein told Ars. There are now so many coronavirus cases that it will require additional weeks of widespread social distancing measures to bring the outbreak under control.

But as these measures start to have an impact and infection rates fall, testing will allow public health officials to precisely target further suppression efforts. Officials will be able to identify areas where the coronavirus has been stamped out and people can safely resume normal activities. They'll identify other areas that remain coronavirus hotspots and require more public health resources. As infections become rare and testing becomes plentiful, officials will be able to test close contacts of newly afflicted individuals, making it less likely that a single new coronavirus case will turn into a cluster of them.