Let’s get this out of the way up front: you probably won’t get tested for the Coronavirus, unless your situation or symptoms are critical. In the US, there simply are not enough test kits to do widespread testing. In China and South Korea, widespread testing has helped to slow the spread of coronavirus. By finding infected individuals early—before symptoms start—it’s easier to isolate them and stop them infecting others. But the U.S. has been much slower to test people for COVID-19, with the Centers for Disease Control and Prevention (CDC) choosing to develop its own proprietary test instead of using methods promoted by the World Health Organization (WHO).
What is the testing capacity for COVID-19 in the U.S.?
At the beginning of March, U.S. testing capacity was around 7,000 per day. That number has expanded fast. As of March 16, conservative think tank AEI estimated a capacity of 36,000 tests per day, as private companies and state governments ramp up their testing plans. For instance, University of California-San Francisco plans to test at least 1,000 people per day in its labs, and New York mayor Bill De Blasio said NYC labs would soon test 5,000 people per day.
Lab supply company Thermo Fisher Scientific had 1.5 million tests ready to go in mid-March with plans to produce 2 million tests per week. But this just means supplying the equipment, not performing the tests. A lack of trained personnel is already a problem, with a University of Washington lab recruiting volunteer grad students and academics to help with tests in Seattle, one of the nation’s biggest outbreak zones.
How do COVID-19 tests work?
COVID-19 tests usually begin with a nose or throat swab—that’s where the virus is most likely to be found. The swab is then sent to a medical laboratory and checked for the presence of the coronavirus. The lab uses a polymerase chain reaction (PCR) to multiply the small amount of DNA from the swab into a larger sample, allowing lab technicians to see if the coronavirus DNA is present. This is all possible thanks to Chinese researchers publishing the coronavirus genome in January.
PCR tests are not instant – typically taking a few hours to complete. In the U.S., tests were further slowed by bureaucratic confusion and faulty kits provided by the CDC.
While different countries and healthcare providers are using different test kits (like the CDC versus the WHO), the overall method is the same. These PCR tests can only be done by trained professionals with the right lab equipment, and the current U.S. infrastructure can’t handle millions of tests at once. You can’t just walk into your doctor’s office and expect them to have a PCR machine.
The CDC’s first round of test kits went out on Feb. 5, and several labs quickly reported errors and malfunctions. The CDC promised to distribute updated kits, but in the meantime, samples had to be sent to the CDC for testing. This is why doctors were told to prioritize people with obvious symptoms: There simply weren’t enough tests for everybody. In turn, this led to the U.S. recording fewer “confirmed” cases of COVID-19, allowing an unknown number of infected people to fall through the cracks and possibly unknowingly infect others.
America’s testing system earned unfavorable comparisons to other countries—especially South Korea, since both countries announced their first confirmed COVID-19 cases on the same day, Jan. 20. Over the next two months, Korea tested nearly three times as many people than the U.S., testing more than 290,000 people compared to 112,000 here in the states.
How reliable are COVID-19 tests?
Tests based on the PCR process are very commonly used for identifying viral and bacterial infections. While the test is reliable, the results are dependent on the quality of the sample on the swab. Since the COVID-19 virus is more likely to be found in the lungs and may be missed by a nose or throat swab there is a slight chance the test will fail to recognize the presence of the virus. There have also been reports of false positives. However, as of right now, this test is the most reliable method of detecting COVID-19.
Researchers are currently developing new ways to detect the virus. We’re also seeing an influx of mail-order tests that people can perform at home—tests that aren’t FDA-approved and may not be reliable. It’s best to have a test performed by a medical professional and to follow self-isolation guidelines if you suspect you’re already infected.