NY Times: Positive Covid test results misleading…

Up to 90% of people testing positive carry inconsequential amounts of the virus
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When COVID case counts surged in July, most “experts” said that — after a time delay — fatalities would surge, too.

They didn’t, causing a lot of head-scratching.

Now the consensus explanation for a statistically significant decline in the infection-to-fatality rate (IFR)  is that (1) more asymptomatic people (i.e. minimally effected) were being tested (2) those testing positive were skewed to to younger age groups with IFR rates, and (3) more effective medical treatment and therapeutic drugs were saving more seriously effected patients.

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The New York Times has served up a scientific explanation…

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According to the NYT

The most widely used diagnostic test for the new coronavirus, called a PCR test, provides a simple yes-no answer to the question of whether a patient is infected.

But, the standard PCR tests diagnosing huge numbers of people who may be carrying relatively insignificant amounts of the virus.

Most of these people are not likely to develop serious symptoms and are not likely to be contagious.

In other words, many of those getting a positive test result are inconsequentially positive.  Their so-called viral load is too low to effect them … or anybody else.

Digging a little deeper…

The PCR test amplifies genetic matter from the virus in cycles.

The fewer amplification cycles required to trigger a positive reading, the greater the amount of virus, or viral load, in the sample.

This number of amplification cycles needed to find the virus, is called the cycle threshold.

Most labs set the limit at 40 amplification cycles, a few at 37. This means that you are positive for the coronavirus even if the test process required as many as 40 cycles, or 37, to detect the virus.

The CDC says that if more than 33 cycles are required to yield a positive test result then the result is, in effect, a false positive.

Some doctors say the cut-off should be 30 cycles.

So what?

In July, the NY state lab identified 872 positive tests, based on a threshold of 40 cycles.

With a cutoff of 35 amplification cycles, about 43 percent of those tests would no longer qualify as positive.

About 63 percent would no longer be judged positive if the cycles were limited to 30.

Similarly, in Massachusetts, from 85 to 90 percent of people who tested positive in July with a cycle threshold of 40 would have been deemed negative if the amplification cycle threshold was 30 cycles.

Said differently, a vast majority of positive COVID tests are technically “positive” … but, at a practical level, they are inconsequentially so … they either have a very low viral load or, with amplification, are detecting dead or  inactive cells … which is why they neither result in or cause COVID deaths.

It’s as simple as that.

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P.S. If you get a positive PCR test, ask your  doctor if the lab reported the number of cycles.

They probably didn’t, but …

If they did and it’s over 30 you’re entitled to sigh of relief — your case is probably pretty mild.

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