What is Rapid Antigen Testing?

May 25, 2021

You may have heard of it referred to as a rapid test, an at-home test, “just like a pregnancy test,” or maybe even the phrase “lateral flow test,” but these all can fall under one singular umbrella: rapid antigen testing.

But what exactly is rapid antigen testing?

The Big Picture

  • Testing for something different than PCR
  • Antigen testing helps you proactively protect others
  • And a form of others protecting you — they figuring out if they can transmit virus to you
  • Rapid and cheap because no lab equipment is necessary — do it yourself, at home or at work  

Now down to brass tacks:

First, let’s define a key term: an antigen. It’s the part of an infectious agent that your body recognizes to trigger an immune response, so this can be something like a protein on the outside of a virus.

What a rapid antigen test does is identify antigens in a human sample by flowing that sample over a set of molecules that serve as probes because they can bind to the antigen of interest–if it’s in the sample.

This usually means that the infectious agent has to be exactly that–infectious, because it needs to be viable enough for whole antigen to be present. This is in contrast to detecting the genetic material of an infectious agent like a virus in a sample, because the RNA of a virus (like SARS-CoV-2!) can hang around in a sample for longer than it actually is able to infect a host, simply because of how RNA decays in contrast to something like a protein that would be the antigen on the outside of such a virus.

As for the rapid piece, these tests are relatively quick (usually under 30 minutes) because all the molecular pieces needed for analysis are in the test itself, and there’s no need for sample processing or temperature changes to drive a chemical reaction, for example. By design, if there is antigen in the sample to bind to the “probe” molecules, a simple internal chemical reaction that is already set up and ready to go then displays colors in the form of easy-to-read lines for a quick result!

CareStartTM COVID-19 Antigen tests are an accurate, American-made option for rapid testing. Learn more about how to purchase and implement serial rapid testing using this EUA-authorized tests.

The CareStart™ COVID-19 Antigen test has not been FDA cleared or approved. This test has been authorized by FDA under an EUA for use by authorized laboratories and at the Point of Care by medical professionals operating under a CLIA Certificate of Waiver, Certificate of Compliance, or Certificate of Accreditation.

The CareStartTM COVID-19 Antigen test is manufactured by Access Bio Inc. for Intrivo. CarestartTM  is a trademark of Access Bio, Inc.