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[News Focus] COVID-19 self-testing may be game changer

Stung by resurgence of virus cases, Korea warms up to quicker, more convenient testing, albeit a little less accurate

By Lim Jeong-yeo

Published : Dec. 17, 2020 - 15:13

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Kim Gang-lip, Minister of Food and Drug Safety, speaks with representatives of in-vitro diagnostics companies on Wednesday (Yonhap) Kim Gang-lip, Minister of Food and Drug Safety, speaks with representatives of in-vitro diagnostics companies on Wednesday (Yonhap)
Even before the novel coronavirus got out of China late last year, South Korean government and diagnostic firms knew what was coming and what they needed to do.

The insight made the country the world’s main supplier of COVID-19 test kits during the initial phase of the pandemic.

Nearly a year later and faced with fierce new waves of infections threatening to undermine the country’s early success in the virus fight, officials from the government and industry officials met Wednesday to come up with a better weapon – at-home kits that can be purchased at local pharmacies without prescription.

“Imagine a pregnancy test, but for COVID-19 and using nasal discharge,” Lee Min-jun, a representative of the association of in-vitro diagnostics firms in Korea, told The Korea Herald.

Lee, who is also director of research and development at Wells Bio, was among the participants of Wednesday’s meeting between the industry and the Minister for Food and Drug Safety.

In the meeting, the Drug Ministry, which has until recently displayed a prudent stance on devices invented for rapid COVID-19 diagnostics, pledged support.

It was two days after the authorities began using test kits other than ones based on PCR (polymerase chain reaction), which takes about two to three hours in a lab to derive results from.

“The spread of the virus has breached a point where we can no longer respond with the most accurate, standard PCR testing. Now, we need rapid testing,” he stressed.

Not only would this facilitate easier and more widespread testing of coronavirus from the comfort of one’s own home, it would also be a less intrusive method of testing than sticking a 15-centimeter-long swab up the nose.

The swab that collects the testing sample from the deep nasopharyngeal cavity is difficult for individuals to do at home and could cause bleeding if directed the wrong way.

What’s needed for quick and easy home testing is an antigen test using nasal discharge samples, Lee said.

“Blowing one’s nose and collecting a droplet of the discharge from the nose tip would yield a result in 10 to 20 minutes,” Lee said, “Just like a pregnancy test, the device will display double line for positive and a single line for negative.”

Antigen tests derive the result by picking up a person’s antigens formed against an invading virus. If conducted in the very early phase of the virus infection, there is a chance the test may fail to make an accurate detection.

But while the antigen tests may fall short in accuracy compared to the laboratory tests for coronavirus genetic material using PCR, they have the upper hand in price competitiveness.

“Taking the test two or three times will be enough to make an accurate diagnosis,” Lee said.

A PCR test currently costs roughly 80,000 won ($73) in Korea, while an antigen test is 8,000 won.



Why is the antigen technique best for at-home tests?

Currently, there are three ways of conducting COVID-19 testing: PCR, antigen and antibody.

PCR testing is the most advanced and accurate laboratory test of the genetic material of coronavirus. It generally takes two to three hours to get test results, with more recent real-time products shortening it to an hour. PCR tests can be run on a nasopharyngeal sample, nasal discharge, and even saliva, but they cannot be conveniently conducted at home.

Antigen tests can run on nasopharyngeal and nasal discharge, but not saliva, as the accuracy and sensitivity of test results noticeably drops below 80 percent when using saliva samples.

Antibody tests require drawing blood, making it difficult for patients to carry out at home.

Given the characteristics of each possibility, the antigen test is the most suitable method for home testing.

However, in the field of antigen testing, Korea is lagging behind.

In the US, discussions about antigen testing have progressed far more than in Korea, perhaps due to the urgency of the situation there.

On Wednesday, the US’ Food and Drug Administration gave emergency use authorization for Australian company Ellume’s COVID-19 home test for the first time.

For Korean companies to follow suit, there needs to be guidelines for the developing companies to fulfill in anticipation of product commercialization, Lee said.

Furthermore, there has to be a reliable supply of nasal discharge samples from suspected and confirmed COVID-19 patients for research and development purposes. This is where the nation’s Drug Ministry can assist, and as Korea is experiencing its worst outbreak of COVID-19, the Ministry is positively reviewing the request in an effort to do whatever it can to slow down the spread.

By Lim Jeong-yeo (kaylalim@heraldcorp.com)