Rapid Antigen Tests Are Coming. What’s the Best Way to Use Them?

In the coming days, people seeking a rapid test to see if they’re positive for COVID-19 will be able to put information into a federal website and ask for up to four rapid tests. Ten to 12 days later, they should arrive in the mail. 

And over the past weekend, federal rules recently put in place mean that insurance companies now have to reimburse plan members for up to eight over the counter rapid COVID-19 tests per month. 

All this comes as the Biden administration is finally putting its weight behind scaling up the number of rapid tests being manufactured and released to the public – about a billion rapid tests should be online by the first week of February. That should make it easier for people to get their hands on the tests, which have flown off of pharmacy shelves since late December. 

This late-to-the-dance emphasis on rapid tests is in stark contrast to what’s happened in other countries. Former NC Health News intern Mona Dougani, who’s studying in Spain, said tests are everywhere there. 

“You literally go to a pharmacy, you go to a pharm technician and you ask for a take-home test, a COVID antigen test,” she said. “Five to eight euros per rapid test, 15 minutes super quick and easy to do at home.”

But in the U.S. rapid test availability has lagged. And with the flood of Omicron cases, labs that run the PCR tests that have been used all through the pandemic have been completely swamped.

On top of that, the guidance on testing has been confusing and changing in recent weeks. We talked to several testing experts to ask some basic questions and get advice on the way to think about testing going forward. 

First, the basics

Two years ago, few members of the general public had ever heard of a PCR test, much less had one. But now, it’s hard to find someone who hasn’t had one – or multiple – PCR tests. 

PCR tests, short for polymerase chain reaction, are tests used to detect genetic material of the virus. 

“PCR testing detects everything,” said Laura Murray, the area medical director for Greensboro-based Cone Health. “Everything that used to be COVID, or is COVID, or is infectious, isn’t infectious anymore, is debris from prior infections.” 

She described PCR as “extremely, exquisitely sensitive.” 

“It’s not always useful when we’re trying to decide if somebody is infectious, is a risk to others,” Murray said.

Melissa Miller, a professor in the pathology department at the school of medicine at the UNC Chapel Hill also runs the microbiology lab services for UNC Health.

She explained that PCRs can pick up the presence of an infection that’s really new, maybe only a day or two old, before a person shows symptoms. 

In contrast, she said, a rapid test that looks for antigens “is actually looking for a protein that lives on the outside of the virus, so you can see it, and you’re able to detect it in these tests.”