CHARLOTTE, N.C. — Freezing temperatures and winter weather once again slammed the Charlotte area, forcing healthcare providers to again shift their plans for COVID-19 testing. StarMed Healthcare kept only four sites open on Saturday, albeit with delayed starts and early closings.
People still turned up, with cars covered in snow and the heat blasting inside. They showed up in the dozens.
That's led many people to turn to at-home testing, but even those are scarce. Medical correspondent Dr. Sujatha Reddy said using at-home tests must be done with discernment.
"If you have someone who has symptoms in a household or was at an event where someone turned up positive, it makes sense to test that person," she said.
If one person in a family tests positive, then Reddy said advises to go ahead and test the entire family. But if the test is negative, wait and then test that person again.
"With the at-home test, you may get a false negative," she acknowledged.
Dr. M.G. Finn, who is the James A. Carlos Family Chair for Pediatric Technology at Georgia Tech, said the omicron variant could be able to evade detection by at-home kits.
"The chances are a little bit more that those kinds of tests will not detect the new variant," he said.
Finn explained why: the rapid antigen tests are able to latch onto specific proteins on the outer shell of the virus in order to detect it. However, variants like omicron may have altered proteins, meaning antigen tests may be able to dodge detection.
"If I grab onto this coffee cup -- if this coffee cup were to change shape and become a mug and my hands were too small, my hands might not be able to grab it as well," he said. "And that's what a change in the variant does to an antigen test."
Antigen test manufacturers are now factoring this in, using the latest information about coronavirus variants to release new kits. However, it's not an instant process, Finn warned.
"It takes time to propagate through the commercial system to make them available," he said.
Still, Finn said the rapid tests can be used as a guide. PCR testing, however, is still the gold standard.