How it works, why we need it, and why it’s taking so damn long for the US to get people diagnosed.
https://www.wired.com/story/everything-you-need-to-know-about-coronavirus-testing/
Testing
A lot has been made about testing for COVID-19 but it is far from straightforward. There are many publicly acknowledged problems with testing procedures and accuracy of the results. Statistician Nate Silver writes, numbers are meaningless unless you understand how they’re counted.
Browse the articles related to this topic below.
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At present, polymerise chain reaction (PCR) and antibody testing are the dominant ways that global healthcare systems are testing citizens for Covid-19. Both techniques have their caveats, and as the crisis unfolds researchers are looking into alternative ways to screen for the deadly disease. Chloe Kent looks into the science behind PCR and serology, and what alternatives are starting to present themselves.
Different paths to the same destination: screening for Covid-19
A scientist at Public Health England said the in-house tests that have been in use since February are performing worse than commercial kits, which labs have been advised to switch to by the end of the month.
Coronavirus tests given to thousands of NHS staff so they could return to work have been found to be flawed and should no longer be relied on, a leaked document reveals.
A memo sent by PHE’s senior lab team flags up several concerns about the tests, despite the fact hundreds of thousands have been carried out
The industry of mass-testing the population at least twice per month was laid out in the National Covid-19 Testing Action Plan by The Rockefeller Foundation, published in April 2020.
Note: See embedded video below for commentary from Fiona Marie Flanagan and Dave Cullen.
We’ve been hijacked by our technologies, but left illiterate about what they actually mean. In this case, I am in the rare position of having known, spent time with, and interviewed the inventor of the method used in the presently available Covid-19 tests, which is called PCR, (Polymerase Chain Reaction.)
NHS laboratories are using a flawed test for coronavirus, according to a leaked Public Health England document seen by openDemocracy. Experts warn that the test fails to detect up to 25% of positive COVID-19 results.
Although the current test is known to be inconsistent, NHS labs are nonetheless being advised to continue using it, while an urgent “migration” or shift to a commercially available test takes place.
- UK policy on lockdown and other European countries are not evidence-based
- The correct policy is to protect the old and the frail only
- This will eventually lead to herd immunity as a “by-product”
- The initial UK response, before the “180 degree U-turn”, was better
- The Imperial College paper was “not very good” and he has never seen an unpublished paper have so much policy impact
- The paper was very much too pessimistic
- Any such models are a dubious basis for public policy anyway
- The flattening of the curve is due to the most vulnerable dying first as much as the lockdown
- The results will eventually be similar for all countries
- Covid-19 is a “mild disease” and similar to the flu, and it was the novelty of the disease that scared people.
- The actual fatality rate of Covid-19 is the region of 0.1%
- At least 50% of the population of both the UK and Sweden will be shown to have already had the disease when mass antibody testing becomes available
Summary from 21st Century Wire.
Dr. Scott Jensen mentions the financial incentive to mark a patient with COVID-19.
It seems that the British government’s assumption that COVID-19 would infect 80 percent of the population was borrowed from a 2015 flu pandemic planning report.
We compared the results of an antigen test (ELISA) with those of polymerase chain reaction (PCR) for the detection of rotavirus and norovirus in stool specimens. Rotavirus and norovirus antigen-positive stool specimens were collected, and rotavirus and norovirus PCRs were performed on these specimens. Of the 325 rotavirus antigen-positive specimens, 200 were positive for both assays and 125 were PCR negative. Of 286 norovirus antigen-positive specimens, 51 were PCR negative. Comparison of the lower limit of detection showed that rotavirus PCR was 16 times more sensitive and norovirus PCR was over 4,000 times more sensitive than the ELISA. Discrepant results between ELISA and PCR were common, and the possibility of false-positive and false-negative results should be considered with rotavirus and norovirus assays.
Minnesota State Senator says Department of Health guidelines instruct doctors to list Covid19 as cause of death, without being tested.
Lethality of COVID-19 has been overestimated and is likely to be in the range between normal and pandemic influenza.
Felix Scholkmann is a biophysicist at University Hospital Zurich, University of Zurich, Switzerland.