The New York Times, the old grey lady of eastern seaboard journalism, has published a blockbuster story, “Your Coronavirus Test Is Positive. Maybe It Shouldn’t Be,” that should be widely reported in other media formats. So far, the substance of the story has remained pretty much on the media shelf.
The Times has discovered that the easily corrected, most often used calibration for Coronavirus testing is not useful for “containing the spread of the virus.”
According to the Times, “In three sets of testing data that include cycle thresholds, compiled by officials in Massachusetts, New York and Nevada, up to 90 percent of people testing positive carried barely any virus, a review by The Times found.
“On Thursday [8/10/2020], the United States recorded 45,604 new Coronavirus cases, according to a database maintained by The Times. If the rates of contagiousness in Massachusetts and New York were to apply nationwide, then perhaps only 4,500 of those people may actually need to isolate and submit to contact tracing.”
“The most widely used diagnostic test for the new Coronavirus, called a PCR test,” the paper notes, “provides a simple yes-no answer to the question of whether a patient is infected.” However, similar PCR tests for other viruses, “do offer some sense of how contagious an infected patient may be: The results may include a rough estimate of the amount of virus in the patient’s body.”
The problem is that current PCR tests are too broadly calibrated. The PCR test, “amplifies genetic matter from the virus in cycles; the fewer cycles required, the greater the amount of virus, or viral load, in the sample. The greater the viral load, the more likely the patient is to be contagious.” The cycle threshold — the “number of amplification cycles needed to find the virus… is never included in the results sent to doctors and Coronavirus patients [emphasis mine], although it could tell them how infectious the patients are.”
The Times story quotes Juliet Morrison, a virologist at the University of California, Riverside: “I’m shocked that people would think that 40 could represent a positive,”
Currently, the cycle threshold limit is set at 40, which means you are “positive for the Coronavirus if the test process required up to 40 cycles, or 37, to detect the virus.” The figures deployed by most politicians, in the absence of more useful and predictive figures, are designed to induce in ordinary citizens a posture of compliance to gubernatorial edicts that depend upon medically useless data.
Not for nothing is Coronavirus called a “novel” virus. There can be no “science” associated with a novel virus. One wonders how many doctors and reporters in Connecticut would be thunderstruck that the “yes and no” figures dangled before them were, to put the best face on it, medically misleading but politically useful.