South Korea says recovered coronavirus patients who tested positive again did not relapse: Tests picked up 'dead fragments' of the virus

• Experts say that recovered coronavirus patients who tested positive again were not reinfected, and their virus was not reactivated, as previously feared.
• 263 people who recovered and tested negative subsequently tested positive again, and the Korea Centers for Disease Control and Prevention worried the virus had reactivated after going dormant.
• But the country's infectious disease experts now say the tests were detecting dead fragments of the virus that were left in patients' bodies.
• South Korea was one of the first countries to report a virus outbreak but only 247 people have died there after the country implemented widespread testing and tracing.
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Scientists said that studies show the wave of South Koreans who tested positive for COVID-19 even after they had recovered did not have the virus reactivate after going dormant and the patients were not re-infected by the virus.

South Korea first announced in early April patients who had recovered from and tested negative for the virus later tested positive, which suggested the virus could reactivate or that patients could immediately be re-infected. To date, the country has recorded this happening in 263 patients.

Now the country's infectious disease experts have said the positive result was likely caused by flaws in the testing process, where tests pick up remnants of the virus without detecting whether or not the person is still infected. They say that dead fragments of the virus that were lingering in patients' bodies after they recovered, and that the virus did not appear to be active in the patients.

The Korea Herald reported that Dr Myoung-don Oh, a professor of medicine and the head of Seoul National University Hospital's division of infectious diseases, said on Wednesday that the committee studying the apparent reinfections found little reason to believe the patients had been reinfected or the virus had reactivated.

"The tests detected the ribonucleic acid of the dead virus," Oh, an advisor to Korea's Government and the Korea Centers for Disease Control and Prevention, said at Korea's National Medical Center.

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Experts were already skeptical about the theory that the virus could 'reactivate'

Jeong Eun-kyeong, the director-general of the KCDC, had said in April that the positive test results in these patients could mean that the virus had "reactivated" in the patients after going dormant. Jeong said that the tests were conducted within a "relatively short time" after the patients were declared positive from the virus, so it was unlikely they that they were reinfected with it. He said Korea was researching why this had happened.

"While we are putting more weight on reactivation as the possible cause, we are conducting a comprehensive study on this," Jeong said. "There have been many cases when a patient during treatment will test negative one day and positive another."

But as Business Insider's Holly Secon reported at the time, many experts thought that the idea the virus would go dormant and then reactivate in people was unlikely.

Instead, they said, it was more likely that patients' bodies still had some fragments of the virus in them. This meant that the virus can show up in a test and the patient tests positive, but not that the person is not ill or able to infect others.

Dr. Keiji Fukuda, director of Hong Kong University's School of Public Health, told the Los Angeles Times in March that this was the most likely scenario.

"The test may be positive, but the infection is not there," Fukuda said.

The test picked up false positives, Korean officials say

Oh said on Wednesday that the committee strongly believes this is what happened.

"The tests detected the ribonucleic acid of the dead virus," he said, referring to a molecule of the virus.

He said that dead virus cells can take months to leave patients' bodies after they recover, and that their test could not determine if the virus was alive or dead.

The report of false positives from South Korea comes as countries grapple with unreliable tests for the virus and its antibodies, and are getting false positives and false negatives back.

South Korea recorded no new domestic cases for the first time since February

It also comes as South Korea reports no new domestic infections in a day for the first time since February.

The four new cases reported were from people travelling into the country.

South Korea has now reported a total of 10,765 cases, of which 9,059 people have been discharged, The Guardian reported. 247 people have died.

The country has been a pioneer in the fight to control the spread of virus, and has done so without implementing a nationwide lockdown.

South Korea, one of the first countries outside of China to record cases of the virus, used widespread testing and traced the contacts of those who tested positive.

It also implemented sweeping social distancing rules, including seating people far apart at restaurants. But it did not shut venues, unlike much of the rest of the world. South Korea also said that it avoided any new cases stemming from 29 million people voting in a parliamentary election this month. Voters were made to wear masks and gloves.Read the original article on Business Insider