What to know about COVID-19 home tests

NPR's Eyder Peralta speaks to epidemiologist Michael Mina about COVID-19 home tests, how to use them, and what they do and don't tell us.

Transcript

EYDER PERALTA, HOST:

This holiday season, we are all meeting up with friends and family or thinking about it. And as the omicron variant explodes across the country, getting tested before indoor gatherings is becoming almost a necessity. But many Americans say it's been complicated, if not impossible, to get your hands on at-home tests. Last week, the Biden administration announced it will ship some 500 million at home tests to homes across the country. But it's not clear how quickly those tests can be manufactured or how easy it will be for people to get and pay for them. Joining us to talk about the Biden plan and the best way to test for COVID at home is Dr. Michael Mina. He's an epidemiologist and the chief science officer at eMed, a digital service for health care and testing. Dr. Mina, thank you for joining us.

MICHAEL MINA: Happy to be here.

PERALTA: So what's your reaction to the administration's latest moves? And a lot of these ideas - they look good on paper, but the logistics of this have to be difficult. I mean, older people, you know, who might not be able to navigate websites or order tests - not to mention language barriers. I mean, what can be done to make sure that everyone who needs a test gets one?

MINA: This is such a great question. And access to testing and getting - and breaking down all of the barriers is crucial. Just having the tests out there and available is a big step but certainly not the last step. We need to figure out how to get them literally to people's doorsteps, if possible. We have to guide people who might not be comfortable using these tools to understand how to use them. And then, further, we have to enable people to actually be able to do something with the result, not just know that you're positive but in particular for vulnerable people. And in particular, now that the Pfizer and Merck drugs are being authorized by the FDA, we have to figure out how to enable these tests to be utilized for people to have downstream action, like treatment or like staying in school, going to work or travel.

PERALTA: So I traveled from South Africa, and I knew that I needed to test to make sure that I wasn't carrying omicron. So, you know, I brought some rapid tests with me. And that was a good thing because when I wanted more, I looked everywhere here in Washington, D.C., and all I got were signs in front of pharmacies that said, we're out of rapid tests. You're a big proponent of these tests. Why are they so scarce?

MINA: Well, the primary reason is we have not had a swift enough regulatory process around these tests. The Biden administration has actually been calling for these tests to be scaled up for most of the year since they got into office, in fact, but their hands have been a bit tied because we have a very, very slow and burdensome regulatory process. So the U.S. unfortunately put medicine and medical thinking front and center and has not budged on that and - whereas the U.K., for example, set up a new group to authorize tests and to evaluate them based not on medical metrics but public health metrics. And that allowed them to very rapidly authorize numerous very high-quality tests that could scale to very high numbers. And they also gave large government contracts to a number of manufacturers so that those manufacturers would feel secure if they went out and built a billion rapid tests for that nation.

PERALTA: So let's get practical for a second. Let's pretend that we can get these tests, and we have a family gathering coming up. How would you use them?

MINA: Most people will be lucky if they can get one per person this holiday season. So given that, the best way to use these tests is to use them as soon before the event that you're going into as possible. Use it 30 minutes before you gather. Use it in the car when you're sitting in the driveway. Importantly, don't use it in the cold. You want to use it at around room temperature. But use it very, very soon before the event, and that will give you the best likelihood of being able to weed out all of the people who might be infected and infectious. If you're positive, you should always assume you are infectious.

PERALTA: And what are the limitations of these antigen tests? I mean, what should people know about them?

MINA: Omicron seems to be starting to spread even before the virus really migrates into the nose and is picked up on the swabs. So there is a chance now that even though the test might detect you on days two, three, four or five and six of your infection, that it might not yet be turning positive on day one, the first day that you are starting to become infectious. But there is a good thing that's happening right now, which is that people are actually getting symptoms earlier with omicron. And that probably is because many people are vaccinated or infected. They have immunity, and that immunity gives an early warning sign to say, you are exposed and infected, and people are getting symptomatic really fast. If you have symptoms, assume that you are omicron positive, and don't use your one test that day. Wait a day, maybe two into symptoms to use your test because people are becoming symptomatic a day or so before they're turning positive. And then they'll stay positive regardless of symptoms, you know, for the duration after that they are infectious.

PERALTA: That was Dr. Michael Mina, epidemiologist and chief science officer at eMed. Dr. Mina, thank you so much for your time and the vital information.

MINA: Thank you. Transcript provided by NPR, Copyright NPR.