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Lets discuss the WHO release...
This is the anniversary of the WHO populating their web site with the Drosten test that caused many of these problems.
Document penned on Jan 13th but released during Biden's inauguration on the Jan 20th.
@Bobby_Network
This is the anniversary of the WHO populating their web site with the Drosten test that caused many of these problems.
Document penned on Jan 13th but released during Biden's inauguration on the Jan 20th.
@Bobby_Network
This is a deflection to the labs to understand their LODs.
This is good advice but not very specific advice.
Keep in mind labs running 40 cycles are not necessarily calling at 40 cycles and this is a reminder for labs to scrutinize their IFU/EUAs for the correct LOD.
This is good advice but not very specific advice.
Keep in mind labs running 40 cycles are not necessarily calling at 40 cycles and this is a reminder for labs to scrutinize their IFU/EUAs for the correct LOD.
Protocol that ask to collect out to 45 cycles should be scrutinized as its a sign that something is off in their assay if it requires more cycles to capture Cts out at 40.
Here they speak about Viral Load. Lets dissect this term as its being mis-used.
Here they speak about Viral Load. Lets dissect this term as its being mis-used.
In order for you to have a Viral Load, you need to compare the Viral Ct to something else. Loads are virus particles/host cells.
If you don't measure the host cells, you can't claim to have a viral load measurement. This is not rocket science. It has a name: Delta-Delta Ct.
If you don't measure the host cells, you can't claim to have a viral load measurement. This is not rocket science. It has a name: Delta-Delta Ct.
The Corman-Drosten protocol the WHO first listed does not have this capacity. You need more than one target to make load measurements.
A viral target vs a Human Target.
Some like to use GAPDH for this.
In C19, Human RNaseP is often the target used to prove we have human cells.
A viral target vs a Human Target.
Some like to use GAPDH for this.
In C19, Human RNaseP is often the target used to prove we have human cells.
This often called an internal control or a matrix control.
If you dont have an internal control, what do you compare your Viral Ct to?
It's an important detail as the swab sampling can vary in over 10 Cts for the human RNaseP signal.
Dahdouh et al. https://pubmed.ncbi.nlm.nih.gov/33131699/
If you dont have an internal control, what do you compare your Viral Ct to?
It's an important detail as the swab sampling can vary in over 10 Cts for the human RNaseP signal.
Dahdouh et al. https://pubmed.ncbi.nlm.nih.gov/33131699/
So if the swabs can vary 10 Cts in human collection efficiency, we can't really split hairs about viral Ct of 30 vs 33.
We need Internal controls to perform this normalization.
The UK is missing these too in many labs.
So the WHO speaking about viral loads, begs questions.
We need Internal controls to perform this normalization.
The UK is missing these too in many labs.
So the WHO speaking about viral loads, begs questions.
Here is the Link to the WHO document. https://www.who.int/news/item/20-01-2021-who-information-notice-for-ivd-users-2020-05
This looks like a passive aggressive way to suggest we should not be testing asymptomatic people?
Really?
You don't say?
You mean we can't discern infectiousness the way it's currently being run.
Where have we heard this before?
Really?
You don't say?
You mean we can't discern infectiousness the way it's currently being run.
Where have we heard this before?
This is another circular reference. It's true, but they fail to underscore that disease prevalence is often estimated from qPCR positivity data.
A bit too much recursion for my likings as contamination in qPCR can elevate the disease prevalence and if this feeds back in PPV...
A bit too much recursion for my likings as contamination in qPCR can elevate the disease prevalence and if this feeds back in PPV...
This is poorly worded. I expect no less from an organization that has no accountability.
When TPs go down and FP stay constant, the ratio of TP/FPs changes but the FP risk doesn't increase. The TPs just disappear making the ratio look different.
Overly simple BMJ citation.
When TPs go down and FP stay constant, the ratio of TP/FPs changes but the FP risk doesn't increase. The TPs just disappear making the ratio look different.
Overly simple BMJ citation.
Why simple? It assumes the labs are in a vacuum and that FPs and FNs are a constant as disease prevalence changes. With labs scaling 100 fold in a year, this is not a safe assumption. FP rates can increase as positivity rises if there is contamination. https://laptrinhx.com/uk-s-largest-testing-lab-suffers-covid-19-outbreak-according-to-whistleblower-3137038865/
Here again, they claim clinical context is required to call a positive.
Really?
Is this happening in schools?
So asymptomatic testing without proper informed consent was cool in 2020 but not once the politics changed?
Really?
Is this happening in schools?
So asymptomatic testing without proper informed consent was cool in 2020 but not once the politics changed?
"Provide the Ct to the requesting health care provider"
That's a good first start but let's be clear.
There isn't one Ct value. There is usually 2-3 for viral genes and 1 for a human gene (RNaseP).
Providing one without the others is stupid.
That's a good first start but let's be clear.
There isn't one Ct value. There is usually 2-3 for viral genes and 1 for a human gene (RNaseP).
Providing one without the others is stupid.
Complaints about PCR are not new. They have been voiced for months and the WHO did update their qPCR policy shortly after our Corman-Drosten review published in late Nov.
The WHO drafted a change on the 13th and decided to hold it to release until 20th
https://cormandrostenreview.com/addendum/
The WHO drafted a change on the 13th and decided to hold it to release until 20th
https://cormandrostenreview.com/addendum/
Last week we published an addendum that made these points crystal clear regarding the lack of controls in the CD protocol and the false positive and false negatives 20 different publications have found. https://osf.io/9mjy7
Oddly, the WHO asks users to read the IFUs to scrutinize the proper Ct to use.
But alas, the CD protocol has no guidance here and you are back to finger pointing accountability.
Maybe the WHO shouldn't have such protocols on their website?
https://www.who.int/docs/default-source/coronaviruse/whoinhouseassays.pdf
But alas, the CD protocol has no guidance here and you are back to finger pointing accountability.
Maybe the WHO shouldn't have such protocols on their website?
https://www.who.int/docs/default-source/coronaviruse/whoinhouseassays.pdf
Particularly when the WHO protocols point to NCBI accession numbers that don't contain the E gene they claim can be amplified from such sequences??
Note these sequences only contain RdRp?
How do E genes amplify such samples?
https://www.ncbi.nlm.nih.gov/search/all/?term=KC633203
Note these sequences only contain RdRp?
How do E genes amplify such samples?
https://www.ncbi.nlm.nih.gov/search/all/?term=KC633203
Finally,
I would encourage folks to read @goddeketal anniversary summary of the Drosten mess.
The folks calling this out are vilified and have no financial conflicts. Many are putting their finances at risk.
The folks doing this are unquestioned and have financial conflicts. https://twitter.com/goddeketal/status/1352238574389891072
I would encourage folks to read @goddeketal anniversary summary of the Drosten mess.
The folks calling this out are vilified and have no financial conflicts. Many are putting their finances at risk.
The folks doing this are unquestioned and have financial conflicts. https://twitter.com/goddeketal/status/1352238574389891072
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