How accurate are at-home COVID tests? A Yale Medicine doctor explains

(WTNH) — The federal government is sending out 500-million at-home COVID-19 tests to Americans. But how accurate are these tests? How well do they work?

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The answer is, it depends on how you administer the test and how much of the virus you have in your system.

Dr. Sheldon Campbell, a lab physician at Yale Medicine, explained, “As best we know right now, the home tests are as good against omicron as they were against Delta.”

The at-home test is called an ‘antigen test’, which means it needs more of a virus load in your system to detect the virus. So, if you’re at higher risk of complications from COVID, you should skip straight to the PCR test.

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Dr. Campbell said, “People late in the disease – when they are starting to get to what we call ‘the inflammatory stage’ where they get really sick – sometimes they have pretty low viral loads, and you don’t wanna miss that.”

Doctors say one of the biggest problems with the at-home test kits is that it’s not being administered by a healthcare professional.

You have to start by reading the directions thoroughly. Storage temperatures are important. The instructions tell you to start off by washing your hands with warm water and soap, but Dr. Campbell says you have to be careful and not get that soap or antibacterial on the end of the Q-tip because it can contaminate the results.

Timing, too, is a factor with these tests. Once you take the test, you may have to wait between 15 and 30 minutes for results. If you check earlier or later those results won’t count.

And when it comes to actually putting in the Q-tip up your nose, you have to do a thorough job of that, as well.

Dr. Campbell: “If it says to swab your nose, swab it! Don’t just stick the thing up there in the middle of your nose and pull it out, get some juice on it.”

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Many pharmacies have run out of the at-home tests, so Dr. Campbell says it’s ‘buyer beware’ if you’re buying online; there are a lot of fraud and scams out there.

“There are a whole lot of things you can buy out there on the internet that are not FDA approved, so get one of the FDA approved tests because there are all kinds of weird stuff out there.”

The bottom line is, if you are immune-compromised or have a comorbidity, you need to get the PCR test immediately, as soon as you start showing symptoms. That way, if the test comes back positive you can get treatment faster and get out ahead of it.