By Tia Ghose - Assistant Managing Editor  - Live Science

The test gives results in 45 minutes.

The U.S. Food and Drug Administration (FDA) has given emergency approval to a test that could diagnose COVID-19 in 45 minutes, CNN reported.

The tests were developed by California-based company Cepheid and will be shipped to U.S. facilities by March 30, according to an FDA announcement. However, right now, the tests are likely only going to be used in a hospital setting, where a patient is already in an emergency room or hospital triage wing and needs to be diagnosed rapidly, STAT reported. 

"We don't believe this technology should be used, at least initially, in a doctor's office," David Persing, chief medical officer of Cepheid, told STAT. "This is not a test for the worried well."

Partly, that's because Cepheid's production capacity is limited; it can produce millions of tests over the coming weeks, Persing told STAT. By contrast, other companies with approved tests will be able to produce millions of tests per week by April, according to STAT.

The U.S. has been plagued by a severe shortage of tests, which allowed the new coronavirus SARS-CoV-2 to spread undetected for weeks. Test kits initially sent by the Centers for Disease Control and Prevention were faulty, and for weeks the government forbade local labs from developing their own kits.

Testing has ramped up significantly in the past two weeks, and as a result, the number of confirmed cases in the country has skyrocketed. As of Saturday (March 21), the U.S. had logged more than 24,000 cases, more than half in the state of New York.

As nearly every country in the world races to diagnose and contain new cases, the U.S. is now facing competition for supplies, such as swabs and chemical reagents, that are needed to run the tests.