Testing

What is it

Testing for the virus that causes COVID-19 involves multiple supplies, including a swab and chemical reagents. Because of the highly contagious nature of the virus, testing is a way to stop the coronavirus from spreading: Those who test positive and those they come in contact with are told to isolate.

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1 Nasopharyngeal swab

Used to collect the sample that will be tested for the COVID-19 virus. This is no Q-tip. It is flexible, thin and long enough to go in your nose and all the way back to the spot behind your nose at the top of your throat. During the test, the swab is inserted and rotated to collect a sample.

2 Universal Transport Medium

A liquid into which the swab is placed for transporting the sample to a lab. It is the contents of the liquid that is actually tested for the virus that causes COVID-19, not the swab.

How they’re used

The virus that causes COVID-19 was unknown to scientists before 2019, and there were no tests that could detect it. So developing tests quickly became a global priority, with a university lab in Germany reaching the finish line first. Instead of relying on validated tests, the CDC chose to develop an entirely new diagnostic test — one that the Trump administration claimed would be more accurate.

Initially, labs were only allowed to run the CDC test. It wasn’t until February 29 that the FDA loosened their regulations, allowing labs to run non-CDC tests. And it wasn’t until mid-March, roughly two months after the German test was developed, that the first commercial tests were available for sale and use in the U.S.

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3 Micropipette

Used to measure and transfer small amounts of liquid.

4 Pipette tips

Single-use plastics that are fitted on micropipettes. Each time a sample is transferred, a new pipette tip must be used in order to avoid contamination.

5 Microcentrifuge tube

A single-use plastic tube used to contain mixtures of the test sample.

What went wrong

First, some of the CDC tests didn’t work. Then there weren’t enough to go around. And by the time the federal government ramped up its efforts, the U.S. was facing dire shortages of testing supplies, including swabs. That’s because only a few companies make the majority of the world’s swabs, and as the pandemic spread — not only across the U.S. but around the globe — those companies couldn’t keep up with skyrocketing demand.

Centers for Disease Control and Prevention response timeline, February to March 2020

Feb 4

The Food and Drug Administration issues an Emergency Use Authorization to the CDC for their coronavirus test.

Feb 8

Labs start reporting problems with the results of the tests.

Feb 12

The CDC officially announces that the problem was due to a faulty reagent, which meant labs could not verify results of the test. While the CDC investigates, state labs are told to stop testing, although the CDC’s lab continues to perform tests.

Feb 26

The FDA allows public health labs to begin using the CDC test without the third reagent that was causing issues.

Feb 29

A new FDA policy allows some designated labs to develop and run their own tests while they pursue Emergency Use Authorization with the FDA.

Mar 12

The FDA begins issuing EUAs to commercial test companies, allowing them to begin manufacturing and distributing tests without going through the usual approval process.

Mar 13

President Trump issues a memorandum indicating that states can request flexibility to authorize local labs to develop and perform tests.

Mar 16

The FDA announces an official policy allowing a bypass of federal approval. This move is seen as clearing regulatory obstacles for new tests.

What’s at stake

Testing plays a crucial role in containing the COVID-19 virus. To control the spread of an infectious disease, you have to know how many people are infected. To know how many people are infected, you must have widespread and effective testing. Without it, there’s no way to contain the virus. At this point, more than 200,000 people are dead in the United States, and infection rates continue to spike across the nation.

“You cannot fight a fire blindfolded. And we cannot stop this pandemic if we don’t know who is infected.”

Dr. Tedros Adhanom Ghebreyesus, the director-general of the World Health Organization

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9 The Master Mix

A special solution that prepares the processed test sample for a chemical reaction called PCR. The Mix is combined with a special component that makes it possible to detect SARS-CoV2 — the virus that causes COVID-19 — in the sample, if it is present.

10 PCR machine

Heats and cools the mixture so that the PCR reaction can take place. This reaction increases the total amount of genetic material, making it easier to detect the virus if it is present in the sample.

Supplies today

Massive shortages of testing supplies persist across the U.S. According to a Government Accountability Office report published Sept. 21, states are lacking the swabs, reagents, tubes, pipettes and transport media they need “due to a supply chain with limited domestic production and high global demand.”