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.
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.