Friday, October 09, 2020

Covid19 testing & false positives

Opinion by Allan McNew

In March I was terrified of the pandemic.

The most common and considered most accurate test for Covid19 is the PCR test. Scientist Kary Mullis (d 2019) won a Nobel Prize for developing the PCR technique in 1993. He was outraged that, in his view, the technique was misused for HIV testing. Mullis considered he invented a research tool, not a medical diagnostic tool. He was very critical of Dr. Fauci’s role in the HIV epidemic.

From the FDA website concerning the PCR test: “For Emergency Use Only… This test has not been FDA cleared or approved... This test is only authorized for the duration of the declaration that circumstances exist justifying the authorization of emergency use of in vitro diagnostic tests… Specimen Collection, Handling, and Storage Inadequate or inappropriate specimen collection, storage, and transport are likely to yield false test results... Real-Time RT-PCR Diagnostic Panel is a real-time RT-PCR test intended for the qualitative detection of nucleic acid from the 2019-nCoV… The agent detected may not be the definite cause of disease… Negative results do not preclude 2019-nCoV infection and should not be used as the sole basis for treatment or other patient management decisions… Positive and negative predictive values are highly dependent on prevalence... False-negative test results are more likely when prevalence of disease is high... False-positive test results are more likely when prevalence is moderate to low… Test performance can be affected because the epidemiology and clinical spectrum of infection caused by 2019-nCoV is not fully known... Detection of viral RNA may not indicate the presence of infectious virus or that 2019-nCoV is the causative agent for clinical symptoms.” ( FDA document headlined “CDC 2019-Novel Coronavirus (2019-nCoV) Real-Time RT-PCR Diagnostic Panel” Effective: 07/13/2020)

According to the New York Times up to 90 percent of people testing positive carried barely any virus (NYT, “Your Coronavirus Test Is Positive. Maybe It Shouldn’t Be”. Updated Sept. 17, 2020)

Maybe this explains the plethora of asymptomatic carriers.

The PCR test amplifies genetic material by cycles. The most accurate testing involves 30 cycles, most test proceedures in the US are pushing it to 37 or 40 cycles which brings about false positives, whereas 20 cycles will generate false negatives. What the overkill does is to find fragments of RNA from possibly different types of coronavirus which may not be live in a healthy body. The virus sample needs to be isolated, not contaminated with other genetic material. The test is not indicative of medical diagnosis. (NYT, “Your Coronavirus Test Is Positive. Maybe It Shouldn’t Be”. Updated Sept. 17, 2020) So, do we start with a lab test or by listening to the lungs? What about host factors?

A Johns Hopkins daily state by state testing trends graph show that nationally from April to October positive tests are a small fraction of of total tests (less than 5%) with California, while following national trends, having a lower rate (“Daily State-by-State Testing Trends”. Updated on Sunday, October 4, 2020). If the PCR test is in fact churning out false results, what is the true rate of infection?

According to the CDC to this date there have been 7360785 total US cases with 208118 total deaths (“United States Covid-19 cases and deaths by states”, updated Oct. 4). US Covid19 positive tests per 100,000 is 3303. California covid19 cases per 100,000 is 2108, California Covid 19 death rate is 40 per 100,000 (Statista, “Covid 19 death rates in the United States as of 0ct.1 2020”)

Comparing US and other nation’s Covid19 stats: How are international Covid19 stats developed? Total cases? Active cases? Deaths? Partially or fully symptomatic? 1 to 1 comparison of nations with different size populations? Per 100,000 count? Are testing standards the same in every country? Are testing rates different? Relationship between spread of cases vs spread of testing? Time span and volume of testing? Classical diagnostic medicine vs lab result medicine? Factually infected vs testing positive? Periodic snapshots of cases? Garbage in – garbage out?

Governor Newson is basing his shutdowns on new cases based on potentially massive false positives with the death rate trending down, not hospitalizations going up, and it’s killing our economy.

-- Political Pistachio Conservative News and Commentary

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