Canadian PCR Testing Thresholds

PCR Thresholds for Labs Across Canada

These are the threshold limits for Canadian PCR Tests as of July, 2020. (See Below) 

Source Study: https://www.sciencedirect.com/science/article/pii/S138665322030175X?via%3Dihub

Any test with a cycle threshold above 35 is too sensitive, agreed Juliet Morrison, a virologist at the University of California, Riverside.

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.

This number of amplification cycles needed to find the virus, called the cycle threshold, is never included in the results sent to doctors and coronavirus patients, although it could tell them how infectious the patients are.

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.

“I’m shocked that people would think that 40 could represent a positive,” she said.  A more reasonable cutoff would be 30 to 35, she added.  Dr. Mina said he would set the figure at 30, or even less. 

Those changes would mean the amount of genetic material in a patient’s sample would have to be 100-fold to 1,000-fold that of the current standard for the test to return a positive result — at least, one worth acting on.

“We’ve been using one type of data for everything, and that is just plus or minus — that’s all,” Dr. Mina said. “We’re using that for clinical diagnostics, for public health, for policy decision-making.” But yes-no isn’t good enough, he added. It’s the amount of virus that should dictate the infected patient’s next steps. “It’s really irresponsible, I think, to forgo the recognition that this is a quantitative issue,” Dr. Mina said.

See the full original article [here].
Read additional information [here].

AB (ProvLab) 

Thermocycler: Applied Biosystems.  Test: Life Technologies

  • Reaction: 20
  • Template: 10
  • Positivity: 35 

 

BC (BCCDC)

Thermocycler: Applied Biosystems.  Test: Life Technologies

  • Reaction: 20
  • Template: 5
  • Positivity: 35  

 

BC(BCCW)

Thermocycler: Applied Biosystems.  Test: Life Technologies

  • Reaction: 20
  • Template: 5
  • Positivity: 35 

 

BC (SPH) 

Thermocycler: Roche Diagnostics.  Test: Roche Diagnostics

  • Reaction: 20
  • Template: 5
  • Positivity: 40 

 

BC (VGH)

Thermocycler: Applied Biosystems.  Test: Life Technologies

  • Reaction: 20
  • Template: 5
  • Positivity: 35 

 

BC (VIHA)

Thermocycler: Applied Biosystems.  Test: Life Technologies

  • Reaction: 20
  • Template: 5
  • Positivity: 35 

 

MB (Cadham) 

Thermocycler: Bio-Rad Laboratories, Ltd.  Test: Life Technologies

  • Reaction: 20
  • Template: 5
  • Positivity: 36.5 

 

NB (CHU-Dumont) 

Thermocycler: Roche Diagnostics.  Test: Roche Diagnostics

  • Reaction: 20
  • Template: 5
  • Positivity: 40

 

NL

Thermocycler: Roche Diagnostics.  Test: New England Biolabs

  • Reaction: 20
  • Template: 5
  • Positivity: 33 

 

NS (nsha)

Thermocycler: Applied Biosystems.  Test: Life Technologies

  • Reaction: 20
  • Template: 5
  • Positivity: 35 

 

ON (PHOL)

Thermocycler: ThermoFisher Scientific.  Test: Applied Biosystems

  • Reaction: 10
  • Template: 5
  • Positivity: 38 

 

PE (QEH) 

Thermocycler: Becton Dickinson and Company.  Test: Altona Diagnostics

  • Reaction: 20
  • Template: 12.5
  • Positivity: Not Defined

 

QC

Thermocycler: ThermoFisher Scientific.  Test: Applied Biosystems

  • Reaction: 20
  • Template: 5
  • Positivity: 37 

 

SK (RRPL)

Thermocycler: Applied Biosystems.  Test: Life Technologies

  • Reaction: 20
  • Template: 5
  • Positivity: 36 

 

ON (St-Joseph’s Healthcare) 

Thermocycler: Bio Rad Technologies Ltd.  Test: New England Biolabs
  • Reaction: 20
  • Template: 5
  • Positivity: 45 

 

ON (St-Joseph’s Healthcare) 

Thermocycler: QIAGEN Inc.  Test: New England Biolabs

  • Reaction: 20
  • Template: 5
  • Positivity: 45 

 

ON (St. Michael’s Hospital)

Thermocycler: ThermoFisher Scientific.  Test: Altona Diagnostics

  • Reaction: 30
  • Template: 10
  • Positivity: Not Determined

 

ON (Mt-Sinai)

Thermocycler: Bio-Rad Technologies.  Test: Seegene Inc.

  • Reaction: 25
  • Template: 8
  • Positivity: 40

 

N/A

Applied Biosystems. Test: Applied Biosystems

  • Reaction: 20
  • Template: 5
  • Positivity: Not Determined

 

Thermocycler: Applied Biosystems.  Test: r-Biopharm AG

  • Reaction: 20
  • Template: 5
  • Positivity: Not Determined

 

Thermocycler: Applied Biosystems.  Test: Quidel Corp.

  • Reaction: 15
  • Template: 5
  • Positivity: 30

 

Thermocycler: Applied Biosystems.  Test: SolGent Co., Ltd

  • Reaction: 20
  • Template: 5
  • Positivity: 40

 

Thermocycler: Applied Biosystems.  Test: Perkin–Elmer

  • Reaction: 20
  • Template: 40
  • Positivity: 42

 

Thermocycler: Roche Diagnostics.  Test: Roche Diagnostics

  • Reaction: 20
  • Template: 10
  • Positivity: 36 

I’m not saying the virus doesn’t EXIST. 

What I AM saying is that the PCR testing isn’t determining whether or not someone has it at the recorded amplification they have their machines set at. 
 
This is science. I didn’t write the study… but we can all read it.
 
Not to mention, none of these “cases” mean anything if they don’t standardize their testing to have the same parameters across the country. Which they clearly haven’t done.
 
Here’s a quick metaphor: If you teach someone who doesn’t speak English that a “cat” is called a “dog”, show them a cat, and TELL THEM it’s name is “dog” – they will learn to call that particular animal a dog, regardless if it actually is a cat or not.
 
It’s really hard (impossible for me, so far) to find evidence that they have NOT indeed done the EXACT SAME THING with Covid and a bad strain of the flu. Think about it. And seriously.. feel free to drop some evidence if you disagree. I can’t find any.
 
It seems to me that these labs all just “outed” themselves with this study.  
I can’t read this and still believe their “statistics” are real, or accurate, at all, in the slightest. 
 
If you can, I don’t even know what to tell you.

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