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An Epidemiologist Says At-Home Testing Is Key To Stopping COVID


The kit comes in a little box - inside the box, a swab, a small bottle of solution and a paper or plastic reader that tells you if you've got COVID. The Biden administration says rapid COVID tests that you can take at home will help rein in an explosion of cases as people head back into work, back to school. Harvard epidemiologist Michael Mina has been calling on public health officials to expand rapid at-home COVID tests for months.

Dr. Mina, welcome back to ALL THINGS CONSIDERED.

MICHAEL MINA: Well, thank you so much. I'm happy to be here.

KELLY: You are obviously a fan of the rapid at-home tests. I want to remind people of the facts, of how they stack up against the PCR tests. The rapid tests are antigen tests. PCR tests are the ones that take longer to get the results back but that have been holed up - held up as the gold standard. The rapid at-home tests - how well do they work compared to PCR tests?

MINA: For public health, they work very well. If the question is, am I infectious right now, then these tests are very accurate. The PCR test is the gold standard but as a medical diagnostic. If as a physician, a patient says, I want to know, was I infectious last week, the PCR test can help with that. But the delays in the lack of ready access makes them a much more ill-equipped test to be able to actually curb spread during this pandemic.

KELLY: So if the rapid antigen tests are so useful, why don't a lot of schools take them? My kids' school won't accept them. A lot of employers won't take them.

MINA: Well, in the United States, we have had this misperception that these tests were not accurate. But it took a long time, and a lot of our research was dedicated this past year just to show that we need to hold public health tools to a different set of standards, not worse but different, and that it's actually the speed of a test and not just the molecular sensitivity that becomes much more crucial.

KELLY: If your kid had symptoms but tested negative on a rapid home test, would you rely on that?

MINA: The short answer is yes. But if there are outbreaks in my community and my child has COVID symptoms, then in this climate, I would not send my child to school if they had symptoms. What we're really talking about is how to keep schools safe without having to close down and stop asymptomatic people and otherwise healthy-appearing people from going to school.

KELLY: But just as a parent, if your goal was to find out, is my kid sick, does he have this thing, would you be fine with just doing the rapid test?

MINA: I would. And the reason is there isn't another choice. You can say I want a PCR test, but you're not going to get that result for three or four days by the time you decide to make an appointment, send it out to a lab, get the results. And so I would say, yes, absolutely. This is the best test I have at my disposal right now.

And even if somebody is symptomatic, if they are not turning positive on a rapid test, they are very, very unlikely to be spreading the virus. The symptoms are often the immune response to the virus, so they might have been infectious two days ago. But if they're negative now, they're probably not transmitting now.

KELLY: You just touched on something else that I had been curious about. It's taking longer again to get PCR test results. There was a window where it seemed like you could get a PCR test - at least in a big city where I am - and results were coming back in 12 hours, 18 hours. And now it's taking longer as demand for those ramps back up.

MINA: And we are about to see another testing crisis in this country. While I am extraordinarily supportive of the president's action plan to increase the accessibility and availability of these rapid tests, the vaccinate-or-test mandate that was put in place is going to massively drive up demand for testing. And unfortunately, we do not have the scale of either of those tests to be able to get fast turnaround time.

KELLY: Dr. Michael Mina, a pleasure to speak with you.

MINA: Thank you so much.

KELLY: He's a professor of epidemiology at Harvard's School of Public Health. Transcript provided by NPR, Copyright NPR.