Many nucleic acid tests based on RT-PCR were developed, each with different techniques, specifications, and turnaround time. As the illnesses turned into a pandemic, testing became more crucial. The test supply became inadequate to meet the need and so it had to be prioritized according to guidance. For surveillance, the need for serologic tests emerged. Here, we review the timeline of test development, the turnaround times, and the various approved tests, and compare them as regards the genes they detect. We concentrate on the point-of-care tests and discuss the basis for new serologic tests.
https://www.sciencedirect.com/science/article/pii/S0091674920307296
emergency use of the CDC 2019-Novel Coronavirus Real-Time RT-PCR Diagnostic Panel considering the current public health emergency. Subsequently, on February 29, 2020, an immediately in effect guidance policy was released by the FDA to assist with the expansion of available tests and testing facilities throughout the United States. Since this time and up to April 27, 2020, 48 unique tests were approved for use through the EUA, of which 41 tests are nucleic acid–based tests and 7 are antibody-based tests (Table I, Table II, and III).
The tests consist of nucleic acid extraction and purification from the human specimen using authorized extraction methods/instruments followed by real-time RT-PCR, where the RNA is reverse transcribed into cDNA and then amplified using the primer sets and detected using specific probes.
These tests detect nucleic acid from SARS-CoV-2 in patients suspected to have COVID-19 infection.SARS-CoV-2 is a positive-sense, single-stranded RNA virus. The various PCR-based tests developed amplify different segments of the genome (Fig 1).6, 7, 8, 9 These include the RNA genome segments that code for the spike (S) protein, the nucleocapsid (N) proteins 1 and 2, the membrane protein, and the envelope (E) protein, in addition to different Open Reading Frame segments, 1a and 1b. Open Reading Frame 1b is the RNA-dependent RNA polymerase.
Positive results indicate the presence of SARS-CoV-2 nucleic acid; however, patient infection status should be determined from testing in combination with clinical history and additional diagnostic tools. Negative results do not rule out SARS-CoV-2 infection and should be used in combination with other clinical features and testing to determine patient management.
The timing of the emergence of IgM and IgG specific to SARS-CoV-2 during COVID-19 has been described in few publications.14,20 These indicate that IgM and IgG appear almost simultaneously and with an onset occurring approximately 1 week after the onset of first symptoms, similar to reports of antibody kinetics from SARS-CoV-1 infections.25 Antibody titers vary by severity of symptoms, with levels being highest in the most severe infections. Thus, it is not recommended to use serologic tests to confirm COVID-19 when the nucleic acid–based test results are negative. Serologic tests have shown cross-reactivity with other coronaviruses and can be seen in persons who were negative to SARS-CoV-2 by RT-PCR–based tests and have had no symptoms of COVID-19. Although the serologic tests approved measure antibodies to the S and N viral proteins, not all such antibodies are neutralizing antibodies;
SARS-CoV-2 sgRNAs could be detected in patient sputum out to the 10th symptomatic day, whereas this signal disappeared at day 5 of symptoms in throat swab specimens, suggesting that viral replication continues in the lower airway throughout the second week of infection.12
https://link.springer.com/article/10.1186/s12985-021-01489-0
In this study, most FN [False Negative] results were due to low amounts of SARS-CoV-2 virus concentrations in patients with multiple specimens collected during different stages of infection. Post-test clinical evaluation of each patient is advised to ensure that rtRT-PCR results are not the only factor in excluding COVID-19.
You can smell smoke through a mask that effectively blocks COVID-19 becauseodor molecules are much smaller than the virus particles (like those that cause COVID-19)
Milton William Cooper predicted 9/11. On June 28, 2001, the conspiracy theorist told listeners to his broadcast Hour of the Time that Osama bin Laden was about to be blamed for “a major attack” on a large city.
Cooper was easy to dismiss: he had also told the world that Eisenhower signed a peace treaty with aliens and JFK was shot by the Secret Service.
He was 58, drunk and living alone up a hill in Arizona. But on this occasion, he was right. And in the days that followed the attack on the World Trade Centre, Cooper also warned that he price of intuition would be his own life.
“They’re going to come up here in the middle of the night, and shoot me dead, right on my doorstep,” he said. On November 5, 2001, that, too, is exactly what happened.
Marc Jacobson’s new biography of Cooper – Pale Horse Rider: William Cooper, the Rise of Conspiracy, and the Fall of Trust in America – is a fascinating insight into what they call the “paranoid style” of US
Blue Rider Press
Cooper pretty much hated any and all competition. He hated Art Bell. He hated Rush Limbaugh. He hated every other patriot broadcaster and every other UFO person. To say he didn’t play well with others is an under statement. So he probably would have seen QAnon is competition and hated it too. To me QAnon has little to do with conspiracy or the deep state: The Q message is basically about the new Eden that great Trump figure is going to lead his followers to once the Armageddon against the liberals is over and won. This probably sounds crazier than anything Bill Cooper or Donald Trump ever said, but that’s what spending a few years working on this material does to you.
Biographer Mark Jacobson argues "the Tiru incident itself would not have done much to make Cooper's name in ufology. That opportunity came only a few days later" when he was contacted by fellow ParaNet poster John Lear. Lear, the son of Learjet founder Bill Lear, identified as a pilot who had flown missions for the CIA.[15] Lear was the author of a post titled "The UFO Coverup" which incorporated elements of mythos from Paul Bennewitz, a ufologist who was later revealed to have been fed disinformation by American counter-intelligence agent Richard C. Doty.[15][16] Cooper soon visited Lear, and the two spent much time together from 1988 to 1990.[15]
He later participated in the early radio shows of Alex Jones, who was an admirer of his broadcasts.[30]
On June 28, 2001, commenting on a televised interview of Osama bin Laden at his hideout in Afghanistan, Cooper claimed that bin Laden would soon be "blamed" for a 'major attack' on a large U.S. city, "but don't you believe it". Immediately after the attacks on September 11, 2001, he predicted the U.S. would soon be at war in 'two or maybe three countries'.[31][8] He began broadcasting the "controlled demolition" conspiracy theory on the day of the attacks, which eventually became a center of 9/11 conspiracy theories.[22]
https://www.splcenter.org/resources/reports/conspiracy-theorist-slain-police-shootout/
As it turned out, Cooper, a one-time member of the so-called Second Continental Army of the Republic, was far more dangerous than your garden-variety conspiracy fabulist.
Before law enforcement officers served a warrant for his arrest on charges of aggravated assault with a deadly weapon, Cooper E-mailed pals that “I will … try to kill as many as I can before they kill me.”
False Positives Are a problem for Covid PCR tests!
Technical problems including contamination during sampling (eg, a swab accidentally touches a contaminated glove or surface), contamination by PCR amplicons, contamination of reagents, sample cross-contamination, and cross-reactions with other viruses or genetic material could also be responsible for false-positive results.2 These problems are not only theoretical; the US Center for Disease Control and Prevention had to withdraw testing kits in March, 2020, when they were shown to have a high rate of false-positives due to reagent contamination.5
https://www.thelancet.com/journals/lanres/article/PIIS2213-2600(20)30453-7/fulltext?ref=toiest#box1
the current rate of operational false-positive swab tests in the UK is unknown; preliminary estimates show it could be somewhere between 0·8% and 4·0%
https://www.tandfonline.com/doi/full/10.1080/14737159.2020.1757437#d1e174
False-negative results may occur due to the presence of amplification inhibitors in the sample or insufficient organisms in the sample rising from inappropriate collection, transportation, or handling.
https://www.sciencedirect.com/science/article/pii/S0344033821001047
For instance, Yang et al. reported a false negative rate of 11 % for sputum, 27 % for nasal, and 40 % for throat swabs within the first seven days from onset of illness in 213 patients hospitalized with COVID-19 [12].
https://www.sciencedirect.com/science/article/pii/S0165993620302132
Unfortunately, there is also a high percentage of asymptomatic individuals, making an accurate disease diagnosis of the population a challenging job unless the entire population is tested [7]. A low level of limit-of-detection (LOD) is crucial to shift the diagnostic window of opportunity toward the start of the infection process, to detect newly infected individuals. The test can be based on immunoassays, using antibodies to detect a specific antigen produced by the body's immune system or polymerase chain reactions (PCR) to detect a viral genome sequence. The PCR method is capable of multiplying the DNA with specific sequences in a short time, greatly enhancing the capability of infectious disease diagnostics. Since its invention in 1986, variants of PCR, such as the standard PCR (end-point PCR), the quantitative PCR (qPCR), and the digital PCR have been developed and subsequently applied in the field of molecular diagnostics. For coronaviruses, as with other RNA viruses, a reverse transcription step precedes the PCR (RT-PCR) and transcribes the viral RNA into complementary deoxyribonucleic acid (cDNA). The PCR test becomes the method of choice due to its sensitivity, as well as its specificity, and it is, in principle, capable of detecting a single copy of the virus, resulting in a shortening of the diagnostic window in comparison with immunoassays.
Swine flu, while often mild in humans, can be serious, especially for certain populations. The 2009 H1N1 pandemic in the U.S. caused millions of infections, thousands of hospitalizations, and nearly 13,000 deaths.
The World Health Organization (WHO) declared the H1N1 flu to be a pandemic in 2009. That year the virus caused an estimated 284,400 deaths worldwide. In August 2010, WHO declared the pandemic over. But the H1N1 flu strain from the pandemic became one of the strains that cause seasonal flu.
https://www.mayoclinic.org/diseases-conditions/swine-flu/symptoms-causes/syc-20378103
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