Coronavirus patients ‘can’t relapse once they’ve recovered’

South Korean experts have concluded that hundreds of apparent second-time infections were in fact false positives.

Health authorities in South Korea have concluded that signs of people being reinfected after recovering from coronavirus are actually down to problems with testing.

Scientists began to fear humans are unable to develop long-term immunity against the virus after recovered patients in South Korea, China and Japan tested positive for a second time – sometimes weeks after being discharged from hospital.

But a South Korean expert panel said that more than 270 people who appeared to have relapsed had probably tested positive because of ‘fragments’ of the virus lingering in their bodies.

There is little to no possibility the fragments can reinfect their bodies, the country’s central clinical committee added on Thursday.

The test patients were given is the standard type used worldwide, suggesting the news will reassure other countries fearing recovered patients were relapsing.

Professor Karol Sikora, dean of medicine at the University of Buckingham and former director of the World Health Organisation’s cancer programme, said the findings were ‘perhaps the most important news of the week’.

He tweeted on Thursday: ‘A huge boost for long term immunity. Many scientists were very concerned about those reports.’

The test picks up the virus’ genetic material, RNA, in human samples, but cannot tell whether it is ‘live’ or just a harmless trace that can be left behind when the body recovers.

The committee said in a statement: ‘RNA fragments still can exist in a cell even if the virus is inactivated. It is more likely that those who tested positive again picked up virus RNA that has already been inactivated.’

The immune system fights the disease by attacking infected cells in the lung. Oh Myoung-don, who leads the committee, said coronavirus RNA can be detected in a cell one to two months after it is eliminated.

He also said the coronavirus does not cause chronic illness, separating it from viruses like HIV and hepatitis B which can linger in human cells and reactivate if treatment is interrupted.

South Korea reported just five new cases today, all of them in people who caught the virus outside the country. Nationwide it has reported 10,765 cases and 247 deaths.

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