The U.S. Food and Drug Administration announced that it has granted the diagnostic medical company Quidel the first emergency use authorization for COVID-19 antigen testing. Antigen detection can detect coronaviruses quickly, but it is generally considered to be less accurate than other types of virus detection. THE ANTIGEN TEST FOR COVID-19 IS SIMILAR TO A FAST FLU OR STREPTOCOCCUS TEST, WHICH CAN BE PERFORMED IN A LABORATORY OR IN THE DOCTOR’S OFFICE AND TAKES ONLY ABOUT 15 MINUTES TO PRODUCE RESULTS.
The test commonly used to diagnose COVID-19 is called PCR testing, which is a genetic sequence of the coronavirus found in a cotton swab taken from a sample taken from the patient’s nasal cavity or throat.
Antigen detection is the search for molecules on the surface of the virus. This method results more quickly, but with less accuracy. If the sample tested positive, it would probably be correct, but Quidel’s test had a high false negative rate: it was about 85% accurate.
The FDA says that given the high false negative ratio, antigen testing is only recommended for rapid screening, and that negative results should be confirmed by PCR testing.
Quidel’s chief executive said the company was stepping up production of reagents, officially known as Sofia 2 SARS Antigen FIA, with a goal of producing 1 million copies a week.