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Why the number of 'cycles' is important in testing for COVID-19
Polymerase chain reaction tests are used globally to identify positive COVID-19 cases, but misinformation on them abounds online. We asked an expert to clear it up for us.www.abc.net.au
This below is extracted from the above ABC's site: The headline references PCR cycle misinformation - suggesting it is going to debunk claims that there is question about the test counts - but then goes on to say the exact opposite putting into question huge doubt over the veracity of cases and deaths.
Considering this in light of the vague fact checking and debunking and it's difficult to just ignore the smoke here.
Owen, Chief, et all would suggest my ideology is getting in the way. How precisely I would love to know.
Here the ABC quotes Dr Bruce categorically stating PCR tests over 30 are dubious. But we know most countries have used 40+ cycles. If - "most positive results were detected in the range of 20 to 30 per cycles" why not detail what that number is exactly - or as a percentage. If 90% of cases were detected in the 20-30 cycle range that would be great and hardly impact the overall numbers. But after 12 months they still refuse to say.
If we take Dr Bruce at his world - Most could be just 51% effectively halving the cases and death counts.
But it gets worse - Dr Bruce might be saying most tests (say 51%) are detecting in the 20-30 cycles and 49% are detecting 40 plus cycles. So half of the first tests results and all the second test results are over 40 cycles.
The actually number of cases within the 20-30 cycle range would be 26% and Dr Bruce would still not be technically lying - But our case and death counts would need to be reduced by 75%.
The lack of transparency makes it logical to assume the worst (75% are nonsense) and not the best (10% are nonsense). Why should we assume the best case when we are not given clarity and everyone is so desperate to maintain the hysteria. The lack of excess mortality rates and the fall in so many other causes of death make it compelling to believe 75% of the cases and deaths attributed to COVID are not in fact COVID related at all.
Instead, the most probable conclusion is that merely 25% of deaths attributed to covid are in fact COVID related at all - and as the overwhelming number of those deaths have a range of co-morbidities it is hard to say definitively that there is anything we should be worried about at all - except a slightly more virulent variety of what is typically known as influenza
Have I get something wrong?
The Ct value of a positive test is the number of cycles it took before the signal was able to be identified, Dr Druce explained, with higher values equating to a weaker positive due to less virus being present in the sample.
"A strong positive sample has a lower Ct value — so something that comes up at cycle 15, for instance, is very strong, extraordinarily strong. Something that comes up at Ct 30 is quite low."
A person returning a positive PCR test with a Ct value above 30 would be "very unlikely to be infectious", Dr Druce said, before adding that most positive results were detected in the range of 20 to 30 PCR cycles.
The number of amplification cycles (less than 35; preferably 25-30 cycles); In case of
virus detection, >35 cycles only detects signals which do not correlate with infectious
virus as determined by isolation in cell culture [reviewed in 2]; if someone is tested
by PCR as positive when a threshold of 35 cycles or higher is used (as is the case in
most laboratories in Europe & the US), the probability that said person is actually
infected is less than 3%, the probability that said result is a false positive is 97%
(PDF) External peer review of the RTPCR test to detect SARS-CoV-2 reveals 10 major scientific flaws at the molecular and methodological level: consequences for false positive results
PDF | This extensive review report has been officially submitted to Eurosurveillance editorial board on 27th November 2020 via their submission-portal,... | Find, read and cite all the research you need on ResearchGate





