COVID PCR Testing

A positive test is not necessarily a positive COVID case. We know from studies that we can have false-positive tests. In some studies, there are 60, 70, or 80% false positives because the majority of testing is done by what is called a PCR test. 

PCR stands for polymerase chain reaction test. PCR testing works by making lots of copies (amplifying) of an original swab sample of DNA, running the sample through “cycles” of amplification. The number of cycles is critical. If the number is too high, it will lead to false positives. (Watch this video for an entertaining explanation: bit.ly/37E8cjp.)

In August 2020, the NY Times reported the following: 

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 number of amplification cycles needed to find the virus, called the cycle threshold, is rarely included in the results sent to doctors and coronavirus patients, although it could tell them how infectious the patients are.

A review by The Times found that in three sets of testing data that included cycle thresholds, … up to 90 percent of people testing positive carried barely any virus.

As a result, when labs use a high number of amplification cycles to determine if a person is COVID positive or negative, a high rate of false positives is seen. For example, public health officials are generally no longer recommending retesting after an infection because there may still be dead virus present that can be detected.  The test looks for a piece of a virus but cannot differentiate if it is active or dead.  This is even acknowledged by the World Health Organization.

Dr. Anthony Fauci, speaking to a Virology podcast on July 16, admitted that the PCR test is useless and misleading when run at “35 cycles or higher.”  “If you get a cycle threshold of 35 or more, … the chances of it being replication-confident are minuscule. … You almost never can culture a virus from a 37 threshold cycle. Cycle thresholds over 35 are just finding dead nucleotides.” 

In other words, the accuracy of the test depends on the number of cycles that are run. If enough cycles are run, a positive test will likely result. Currently, there is no standardization regarding the number of cycles a lab needs to use. 

So how many cycles are being used in PCR tests? The answer to this question is surprisingly difficult to uncover. It turns out it varies, but the FDA and CDC, despite these facts, are recommending testing be done using 40 cycles as the threshold! Many labs and tests use between 37 and 40 cycles. 

On October 30, 2020, Governor Newsom contracted with the new PerkinElmer coronavirus testing lab, which claims to have the most sensitive test and the lowest limit of detection over any other PCR test. Within two weeks of this lab’s opening, California had a huge spike of positive tests.

Nobel Prize winner and PCR inventor, Kary Mullis, Ph.D., warned against the misuse of the PCR test as a diagnostic tool and said it was never meant to be used for that purpose.  

These scientific details led the governor of Florida to require COVID testing labs to report the number of cycles they are using to determine positive results in his state. 

Whatever the case, the public would surely benefit from greater transparency and openness when it comes to the reliability of these tests given how much society is affected by their results.

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