Choosing a Test
What kinds of home tests are there for COVID and flu? How do I choose which one to use?
Quick Info
There are two basic kinds of home tests for viruses: antigen tests and molecular tests.
Antigen tests look for proteins from the viruses.
Most home tests are antigen tests. If your test looks like the test in the picture shown here, it's probably an antigen test.
These tests are very good at diagnosing people who are carrying a lot of virus. They are not as good as molecular tests are at finding people who aren't carrying as much virus.
They tend to be less expensive than molecular tests.
Molecular tests look for pieces of the virus’s genetic material.
They're usually more expensive than antigen tests, but they're also better at finding small amounts of virus. They also come with instruments, readers, and apps, which can be helpful.
The most common type of molecular test is a PCR (polymerase chain reaction) test. That's the kind of test most labs use.
PCR tests are really good at finding very small amounts of the virus - that's called being a very sensitive test.
PCR tests can diagnose COVID very early. But they will also continue to give positive results even when an infection is over, because they're triggered by dead pieces of virus.
Another common type of molecular test is a LAMP (Loop-mediated isothermal AMPlification) test.
During the first several days of an infection, LAMP tests are as good as PCR tests at diagnosing an infection.
Both LAMP- and PCR-based home tests are available. If your test runs on a small machine like the one shown in the picture, it's probably a LAMP or PCR test.
Every household in the US can order four free rapid tests at covidtests.gov or by calling 1-800-232-0233 (TTY 1-888-720-7489).
Uninsured or underinsured adults can get free at-home tests and access to telehealth appointments through the US government's Home Test to Treat program.
You can find a free testing site near you on the CDC's No-Cost COVID Testing locator. Tests available at these sites may be rapid tests or PCR tests.
You may be able to get free tests through your local health department.
The Rockefeller Foundation's Project ACT program is offering free at-home COVID tests to individuals in certain ZIP codes while supplies last.
Whenever you test yourself with a rapid test, remember to report your result — whether it's positive or negative.
Yes. Right now, the Lucira by Pfizer COVID-19 and Flu Home Test is the only over-the-counter at-home test available in the US. It is a molecular test that can tell you if you have COVID, Flu A, or Flu B.
Other companies are developing COVID/flu tests now. They should be available soon.
Antibody tests (also known as serology tests) can't tell you if you have COVID right now. All they can tell you is whether you've had COVID or been vaccinated for COVID in the past.
Antibodies are proteins made by your immune system to help you fight off things like viruses and bacteria. When you get infected with a virus, your body makes antibodies that recognize and attach to that specific virus. It can take up to three weeks after the infection for your immune system to make enough antibodies to detect with a test.
The Food and Drug Administration (FDA) decides which drugs and medical tests can be used in the United States. The full FDA approval process can take months to years.
When a public-health emergency happens, there isn’t time for new drugs or tests to go through the entire process. That’s when the FDA can use Emergency Use Authorization (EUA). It allows the FDA to let certain medical products be used more quickly, while still making sure they are as safe as possible. At a minimum, the product must have known and potential benefits that outweigh its known potential risks. In addition, there must be “no adequate, approved, and available alternatives” to the product receiving the EUA.
Most at-home tests for COVID have EUA, including those that come with flu tests. All flu tests that are available in the US have been fully authorized by the FDA.
For more information, check out our blogs, What Happens to Tests After the Emergency Ends? and EUAs: The Beginning and The End.
According to the FDA, all COVID tests that are sold in the US must be checked to make sure that they can detect the most recent variants of the virus. If a test has any trouble detecting a variant, the company that makes the test must let the FDA know immediately. This CNN article explains in more detail.
The FDA then looks at how much trouble the test is having with the variant. If the test still works, just not quite as well, that's called reduced performance. In those cases, the FDA may only require the company to put that information on the test packaging. If the test doesn't work at all, the FDA will take away the test's EUA or approval, or it will require the company to fix the test.
The FDA website lists all tests with reduced performance:
Yes. You will need to take what's called a "proctored" test. That means you take the test while someone else is watching - on Zoom or a similar video service. That person can then send you a document confirming that you took the test and what your result is.
Some test companies offer proctoring, often for an extra cost. You can also find online services that will proctor any at-home test for you.
Here are the test companies that offer proctoring:
These test brands have apps:
CareStart(also called On/Go COVID Antigen Self Test)
Celltrion DiaTrust
CLINITEST
Ellume
FlowFlex (also called On/Go One)
IHealth (also called GoodToKnow)
InteliSwab
Molecular Tests: These all require a device called a reader to run the test.
3EO Health
Cue
Lucira CHECK-IT
Lucira by Pfizer COVID-19 and Flu Home Test
Metrix
According to the National Federation of the Blind, the Cue and Ellume tests can be used nonvisually with a smartphone. The Administration for Community Living website has tips for blind and low vision users of the Ellume COVID-19 tests.
Yes.
3EO Health, Cue, and Matrix, which are molecular tests, don't require you to use a dropper or deal with liquid. They do have small pieces that need to be fitted into the reader that the test uses. The FaStep Pen is designed so that all you have to do is open the packaging and the test, swab your nose, and push the test pieces together. Other brands have the following features:
Test brands that don't require you to open a small foil-sealed vial
Assure-100 (some kits)
BinaxNOW (from Abbott; some kits)
Celltrion DiaTrust
Ellume
HotGen
iHealth (some kits)
InBios Ag Detect
Indicaid
InteliSwab
OSOM
QuickVue
Status
Tests that don't require you to count drops of liquid
ClearDetect (from MaximBio)
COVI-Go (also has an ergonomic handle on the swab)
Ellume (test will work if you add too many drops)
InBios Ag Detect (you use all the liquid in the dropper)
InteliSwab
Lucira CHECK-IT
OSOM (you use all the liquid in the dropper)
QuickVue
Status (you use all the liquid in the dropper)
These days, most tests that use liquid come with pre-filled tubes. The ones that don't are InBios, ClearDetect (from MaximBio), iHealth (some kits), NanoCheck, and SpeedySwab.
A lot of tests require you to set a small vial of liquid upright on a flat surface. To make that easier, most of these tests either come with a tray that has a spot to hold the vial upright or they have a perforated spot on the test box that works as a vial holder. The ones that don't are Assure-100 and COVI-Go.
Yes. The Metrix test works with saliva or with a nasal swab.
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