Are at-home COVID-19 tests accurate? What to know about rapid antigen tests
As the COVID-19 pandemic continues, at-home coronavirus tests have become a common tool for folks who feel ill or want to know their status before heading to a function. And Americans can now get four free tests shipped to their home by the federal government.
But reports of false negatives have left some concerned about how accurate the tests are.
While at-home tests are different from laboratory tests, medical experts say they are still a useful resource.
Are at-home COVID tests reliable?
At-home COVID-19 tests are rapid antigen tests, meaning they are best at detecting the virus “when people have a higher amount of virus particles in their system and are more contagious,” Dr. Emily Landon wrote in an article published by the University of Chicago School of Medicine.
PCR tests, also known as “laboratory tests,” “are far more sensitive than antigen tests.”
“That’s why if someone has COVID-19, but hasn’t yet reached the test’s threshold of viral particles, they may still test negative with an antigen test but positive on a polymerase chain reaction (PCR) test,” Landon wrote.
The Centers for Disease Control and Prevention concurs, advising that “a single negative self-test result may not be reliable, especially if you have symptoms associated with COVID-19.”
While false negatives are possible, at-home tests can still be “a useful tool to have in your COVID-19 arsenal,” Landon adds.
If you start to develop symptoms and test positive on a rapid antigen test, Landon says, then “you have COVID-19.” And you don’t even need to get a lab test. If you’re symptomatic and test negative on an at-home test, you should isolate and try to get a PCR test or take an antigen test again the next day.
“If you’re unclear about what your test result says, isolate and repeat the test in six to 12 hours,” Landon writes. “You’ll likely see a clearer line on the test strip next time.”
If you don’t have symptoms but want to test before seeing people, at-home tests can reduce “but not eliminate” risk, Landon advises.
“Make sure everyone who’s attending an event uses an at-home test as close as possible to the time they’re gathering and understands that a negative test doesn’t guarantee safety or completely prevent exposure,” she writes.
Are some at-home COVID tests better than others?
Like with masks, the pandemic has spurred an influx of fake at-home tests to the market, according to the Federal Trade Commission.
“Using these fake products isn’t just a waste of money, it increases your risk of unknowingly spreading COVID-19 or not getting the appropriate treatment,” the agency stated.
There are ways to make sure the tests you’re purchasing are legitimate.
The Food and Drug Administration evaluates rapid antigen tests and offers a list of ones that have been authorized on their website.
The FTC also recommends checking out the online reviews for tests before buying, researching the seller and paying with a credit card so you can dispute the charge if the tests aren’t as expected.
If you do get scammed, you can report it at ReportFraud.ftc.gov.
