Home COVID-19 Tests
When the COVID19 pandemic started in early 2020 there were many unknowns. In February and March of 2020, COVID19 tests were very difficult to get. Even from the emergency department, we had to get approval to send a test to the state—the only method of testing available at the time.
Since that time, we have moved into a new phase of the COVID19 pandemic in the US. Vaccines are widely available. Tests are easier to perform—even at home!
See below for information about types of tests, available home tests, and our videos on how to perform home COVID-19 tests.
Types of tests available:
Viral Tests:
- PCR/NAAT tests: For these tests, a swab is sent to a lab and results usually take 1-3 days. These tests check for SARS-CoV-2 viral RNA genetic material. If positive, these tests indicate a current or very recent infection.
- Antigen tests: Sometimes referred to as "lateral flow tests," these “rapid” tests can be performed at a pharmacy, lab, doctor’s office, urgent care, or at home. The test looks for a specific viral antigen protein. The rapid antigen tests are less sensitive than PCR/NAAT tests, BUT, the antigen tests are very good at detecting contagious cases of COVID19 (people who are shedding lots of virus who are the most likely to spread the virus to others).
Antibody Tests:
- These detect antibodies to the SARS-CoV-2 virus, from either a prior infection or vaccination. The antibody tests are NOT helpful in figuring out if someone has a current COVID19 infection.
In recent months, several home-based rapid antigen COVID tests have been authorized by the FDA under an Emergency Use Authorization to test for current COVID19 infections. There have been shortages of these tests at times, especially around the holidays, but we hope they will become more available.
Let’s review some of the pros and cons of these rapid antigen home tests:
PROS:
Available, easy to use, quick (typically 10-15 minutes). You can buy a kit, bring it home, and test yourself or your family. These tests have also been used for screening asymptomatic people—such as widespread screening of asymptomatic kids/staff at schools to help identify and stop potential outbreaks of COVID19.
CONS:
There are a some downsides to these tests as well which must be highlighted. These rapid antigen tests are very good at finding current COVID19 infections in people who are shedding a lot of virus. However, early in an infection the viral levels are sometimes too low to be detected. Because of this, if you think you may have COVID19, most manufacturers recommend “serial testing”—taking 2 tests over 2-3 days. This is why many of the home test kits come with 2 tests. False positive tests can sometimes happen, but this is pretty rare. If you test positive, you should let your doctor know about the positive test result. If you test negative but still have concerns for a COVID19 infection (lots of symptoms, high-risk exposure, etc), then you should have a PCR test performed as well.
Now, we’ll review some of the most common rapid antigen tests:
Abbott BinaxNow COVID-19 Antigen Self Test:
- Pros: Easy to use, can be performed with or without the phone app. There is an app (“NAVICA”) which can be used to keep track of your tests.
- Cons: There have been shortages of these tests in recent months
- Availability: Your local pharmacy (maybe) and online
- Price: $14 - $24 for 2 tests
- Instructions: Printed instructions included, optional video
- Test Performance (per manufacturer info):
- Positive % Agreement= 84.6% (“sensitivity”; how often the test is positive when someone DOES have COVID19, compared to PCR)
- Negative % Agreement= 98.5% (“specificity”; how often the test is negative when someone does NOT have COVID19))
Quidel Quickvue At Home OTC COVID-19 Test:
- Pros: Pretty easy to use, does not need a phone app.
- Cons: One extra step compared to BinaxNow, but still very easy
- Availability: Your local pharmacy (maybe) and online
- Price: ~$24 for 2 tests
- Instructions: Printed instructions included with kit, also optional video
- Test Performance (per manufacturer info):
- Positive % Agreement= 83.5%
- Negative % Agreement= 99.3%
iHealth COVID-19 Antigen Rapid Test:
- Pros: Pretty easy to use, has an optional app you can use to track your tests
- Cons: Availability, shipping may be delayed
- Availability: Online from Amazon or their website
- Price: $14-18 for 2 tests
- Instructions: Printed instructions included with kit
- Test Performance (per manufacturer info):
- Positive % Agreement= 94.3%
- Negative % Agreement= 98.1%
BD Veritor At-Home COVID-19 Test:
- Pros: Becoming much more available online. Has a phone app to keep track of your results--BUT this test does not work with all phones
- Cons: A huge downside is the phone app which is NOT compatible with some smart phones. The test can't be interpreted without the app, and if your phone isn't compatible, the test is useless. Keep this in mind and make sure your phone is compatible.
- Price: ~$26.50 for 2 tests
- Instructions: No printed instructions. The app guides you through testing with required to watch videos.
- Test Performance (per manufacturer info):
- Positive % Agreement= 84% overall (ranging from 33% with low prevalence to 94+% with high prevalence, per manufacturer)
- Negative % Agreement= 100%
- Types of Tests, CDC: https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/testing.html
- Testing Information, CDC: https://www.cdc.gov/coronavirus/2019-ncov/testing/index.html
- When to quarantine, CDC: https://www.cdc.gov/coronavirus/2019-ncov/your-health/quarantine-isolation.html
- Vaccine info, CDC: https://www.cdc.gov/coronavirus/2019-ncov/vaccines/index.html
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