Will a 15-minute COVID-19 test solve American test problems?


On August 26, the Food and Drug Administration issued an Emergency Use Authorization for a new rapid antigen test of COVID-19 called the Binaxnow test.

I study public health policy to deal with infectious disease epidemics. The test is one of the most powerful tools to fight the spread of COVID-19. The new test is inexpensive, fast and easy to use. This would increase access to large-scale testing, but barriers to extensive COVID-19 testing remain constant.

Abbott Binaxnow Rapid Antigen Test claims to deliver results in 15 minutes.
Abbott

What type of test is BinaxNOW?

The credit-card size test is an antigen test that detects a specific viral protein from SARS-CoV-2. It costs US $ 5 and does not require a lab or machine for processing.

Testing is simple. A health care worker or technician will use a swab to collect a specimen less than 1 inch inside the nostril. They will then combine the sample with a few drops of chemicals inside the test card. Within 15 minutes, the test strip will show positive or negative results. The test is also combined with an app that produces a digital code that can be scanned to show evidence of a recent negative COVID-19 test.

A sign showing the FDA logo with FDA headquarters in the background.
The FDA approved the Emergency Use Authority for testing, but only for use on patients with symptoms of COVID-19.
AP Photo / Andrew Hornick, File

What does the Emergency Use Authority allow for?

The BinaxNOW trial is currently only authorized for patients who have had COVID-19 symptoms for seven days or less, which is likely to have higher levels of virus in the body. It should be prescribed by a physician and performed by a trained technician or other health care worker.

PCR testing for COVID-19 is currently widely used and is considered the gold standard, but patient samples must be sent to a laboratory and may take a few days to provide results. The new antigen test has been made a cheaper and quicker alternative to PCR testing for clinical purposes in a medical setting. This would add significant potential to an overstretched test system.

The full FDA approval process continues, while the Emergency Use Authority grants doctors initial authorization to preserve antigen testing. If the test is not true or reliable as expected, the authorization may be revoked.

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How accurate is this test?

Health technology company Abbott, which produced the test, reported that when patients had symptoms, agreement with the PCR test for 97.1% for COVID-19 positive cases and 98.5% for COVID-19 negative cases Was. This is sufficient for diagnostic settings where accuracy is important.

However, true accuracy may be lower because the performance testing group was only 102 people and the accuracy has not been validated by the FDA as part of the full approval process. There will inevitably be some inaccurate negatives and incorrect positives with the BinaxNOW test because the accuracy is not 100%, but the FDA will monitor the data to ensure that the test meets the reported accuracy.

People waiting in a row of cars with health care workers standing under pop-up shadow structures.
The test has limited access to long lines and slow turn-around times, but the new Abbott exam should be much easier and faster.
AP Photo / Nati Harnik

Can this test be used for comprehensive screening?

The BinaxNOW Test is inexpensive, fast, mass-produced and easy to use outside of a lab. This makes it a promising candidate for extensive screening. However, the trial is currently only authorized for people with COVID-19 symptoms.

This is a hindrance because an estimated 40% of all COVID-19 cases are asymptomatic and these people are probably not aware that they are contagious. To maximize the effectiveness of any COVID-19 screening program, it is important to test people to see if they have symptoms.

Health care providers have been able to prescribe the BinaxNOW test for asymptomatic patients for off-label use, but health officials do not yet know how accurate the test is on asymptomatic people.

Is this exam a game-changer?

The broad expansion of test access made possible by the BinaxNOW test will almost certainly overtake a small number of erroneous results. Abbott plans to build 50 million trials per month starting in October. This will quickly exceed the 76 million COVID-19 trials conducted in the US over the past six months.

Broadly, frequent testing is effective in slowing the spread of coronaviruses. The new testing capability made possible by the authority of this rapid antigen test represents a major advance in bringing the epidemic under control.