Economist Martin Zelder of UNC-Chapel Hill submits the following column:


North Carolina’s coronavirus positive test rate remains somewhat high — 7.2% on average over the last week — while tests are being given at a record pace. Indeed, on June 12, 23,020 tests were given — meaning that one out of every 460 North Carolinians was tested on that day alone! Or consider the total number of tests given to date in North Carolina: 638,479. If these represented tests given to different individuals in our state of 10.5 million, this would mean that 6% of N.C. residents have been tested.

Hmmm. We have a relatively high positive test rate and lots of tests being given. What might this mean? Possibility 1 is that the coronavirus is a continuing problem — this is the narrative Gov. Roy Cooper and DHHS Secretary Mandy Cohen are reciting. But consider Possiblity 2 — that the 638,479 number is not the number of different N.C. residents tested, but rather the number of tests given. In other words, it reflects that some people have been tested multiple times. Consider the CBS News report of a woman who has recorded eight positive tests within seven weeks ( tests-50-days/). She has been repeatedly retested because she is a nurse, undoubtedly a common practice for many workers in health care and other jobs.

So, here are some questions to which we should be demanding answers from Roy Cooper and Mandy Cohen:

  • What is the true positive test rate — that is, the number of distinct individuals who have tested positive?
  • How much are current positive test rates inflated by repeated retesting of individuals who are either infected or who test positive despite no longer being infected (as documented at:
  • How does the rate of positive tests in congregate-living situations (nursing homes, correctional facilities) compare with the rate of positive tests for the vast majority of North Carolinians not in congregate living?

This last point gets at how much risk the vast majority of us face. The state’s data show that coronavirus infection and death rates are much higher in congregate-living situations. This means that the true risk for those of us not living in these situations is much lower than the state’s official figures.

All of this implies that the infection rate generated by the state of North Carolina exaggerates the problem we really have, and distorts the debate as to how long onerous restrictions on human freedoms should continue.