Rapid Testing Is Less Accurate Than We Thought; Will Mass Testing Still Drive COVID-19 'Towards Extinction?'

This summer, the hope of antigen tests emerged as a blessing. The argument goes with repeated usage. These quick and inexpensive coronavirus checks would recognize extremely contagious individuals while providing a green light to good Americans to go back to normal. However, the scientific community remains divided on antigen tests' accuracy and if mass and frequent rapid COVID-19 testing could make a large dent in the pandemic within six weeks.

More than 150 million assessments for nursing homes and colleges were bought by the U.S. Department of Health and Human Services, costing more than $760 million. But it quickly became apparent that antigen testing faced a different range of challenges, called after the viral proteins or antigens that the test identifies. Unlike laboratory-based molecular PCR experiments that identify snippets of the virus's genetic material, antigen tests are less reliable, and only samples with a higher viral load can be identified.

Hong Kong Mass Covid-19 Testing Begins
HONG KONG, CHINA - SEPTEMBER 01: Healthcare professionals wearing personal protective equipment (PPE) conduct swab tests at a makeshift testing site in the Queen Elizabeth Stadium on September 1, 2020 in Hong Kong, China. Covid-19 testing programme begins at 141 sample collection centres across all 18 districts in city. Anthony Kwan - Pool / Getty Images

Questions on accuracy

Experts suggested the antigen tests should have released antigen tests specifically to populations of outbreaks, rather than allowing them to function almost as well in broad numbers with asymptomatic persons, with the advantage of hindsight. Knowing that they might yield inaccurate findings, the government should have ensured that clinics had enough to minimize false negatives and access to more reliable PCR tests to root out false positives for repeat research. Scientists said government departments who were conscious of the experiments' drawbacks should have built up trust by being more open about them and how to view the findings.

HHS defended the tests and threatened Nevada with unspecified penalties after health care employees in Nevada and Vermont confirmed false positives before state authorities decided to consider utilizing them in nursing homes. It took the U.S. a couple more weeks. On Nov. 3, the Food and Drug Administration released a warning confirming what Nevada had experienced: Antigen analyses were vulnerable to false positives, the FDA warned.

A separate study indicates quick mass testing would drive the pandemic into extinction.

A recent study by scientists at the University of Colorado Boulder and the Harvard TH Chan School of Public Health, meanwhile, indicates that mass rapid COVID-19 testing every three days within six weeks can help push the pandemic to extinction, including targeting those who do not display signs of infection.

According to a Business Insider report, the group of researchers indicates that even though rapid testing is less effective, the findings would allow public health agencies to have more focused initiatives and prevent lockdowns impacting the economy.

In comparison, quick processing is easier, so it is plausible to provide periodic mass testing.

In contrast to the COVID-19 lab test that usually requires days, fast processing often returns the findings in a matter of minutes.

By evaluating half of the United States people regularly, they would easily separate someone who tests positive in a fast test and isolate them from others who are well, which will create a huge difference according to the researchers.

According to the report published in the Science Advances research journal, accelerated monitoring every three days of 75 percent of a city's population for COVID-19 will decrease the amount of infected by 88 percent, which is "sufficient to drive the epidemic toward extinction within six weeks." to the researchers.

"Our big picture finding is that, when it comes to public health, it's better to have a less sensitive test with results today than a more sensitive test with results tomorrow," said Daniel Larremore, a computer science professor at the University of Colorado Boulder and the lead author of the study.

Instead of forcing people to remain indoors so that one sick person won't transmit it, Larremore has said that the exam would make it such that only those who are ill would stay indoors, and the others will go on their lives.

Michael Mina, the study co-author who is also a professor of epidemiology at Harvard, claimed that these tests are "extremely effective" in detecting COVID-19 when people are contagious.

Experts remain divided about the issue.

According to a New York Times report, the research community remains polarized on antigen studies' promise.

The primary argument for antigen testing is disease prevention. A string of studies indicates that large viral loads are identified accurately by antigen analyses. Since humans are more contagious while having elevated virus loads, much more prone to harm, anyone would be flagged by testing. There are no large-scale, peer-reviewed trials to date that demonstrate how the antigen technique has curbed outbreaks on the field.

People need to understand that we live in an environment where many people are unknowingly super-spreaders without rapid checking, Karan said. Asymptomatic individuals with elevated virus loads transmit around 40 percent of pathogens, so antigen tests should not be ignored, albeit incomplete, he added.

And those who are more cynical stated that a focused solution to lower-risk conditions such as colleges, or outbreaks in remote areas where PCR is inconvenient, may be beneficial rather than nursing homes where a single error might set off a deadly chain.

Melissa Miller, director of the clinical microbiology laboratory at the University of North Carolina, said it is completely irresponsible to take a less-accurate examination and claim that it refers to all cases.

Matthew Pettengill, technical director of clinical microbiology at Thomas Jefferson University, said there's no precedence for the government to gamble too much on a substance until it's been fully vetted. "They've put the cart in front of the horse, and we can't see the horse yet."


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