North Carolinians have taken more than three million Covid-19 tests during the pandemic. Almost all- 97%- of the positives came through a molecular test using a polymer chain reaction or PCR. While the test is widely regarded as accurate when it comes to positive or negative, some in the scientific world say it provides an incomplete picture.
Raleigh, N.C. — North Carolinians have taken more than 3 million coronavirus tests during the pandemic, with PCR testing accounting for 97 percent of the positive results. Polymerase chain reaction, or PCR, tests involve rapidly making millions to billions of copies of a specific DNA sample through a process called cycling, amplifying it enough to study in detail. While the test is widely regarded as accurate when it comes to positive or negative for coronavirus, some in the scientific world say it provides an incomplete picture. Dr. Carl Heneghan, director of the University of Oxford’s Centre for Evidence-Based Medicine, told The Spectator magazine in London, that the black-and-white nature of the test is leading to an inflated number of cases. „We have found RNA evidence in shedding for 78 days,“ Heneghan said. „When you’re picking up asymptomatic people, you have no idea if they have an active infection, or did they have it two months ago?“ For its coronavirus test, North Carolina’s state public health lab cycles a DNA sample up to 37 times before deciding whether it’s positive or negative. LabCorp, the main private tester in the state, has a cycle threshold that’s even higher, at 38. „The more times you do that, the less virus you start out with,“ Heneghan said.
