Photo : WPA Pool ( Getty Images )

As the novel coronavirus outbreak continues to spread, with tallies for confirmed cases and total deaths reaching new heights in America this weekend, the World Health Organization (WHO) has begun investigating alarming reports from South Korea where the virus appears to have “reactivated” in covid-19 patients who otherwise seemed fully recovered.




Per a recent Reuters report, officials in South Korea announced Friday that 91 patients received a second positive diagnosis for covid-19, the respiratory illness caused by the novel coronavirus pandemic , after previously testing negative while being considered for discharge. Korea Centers for Disease Control and Prevention Director Jeong Eun-kyeong said in a press briefing that the flare-up could be caused by the virus becoming “reactivated” in patients’ systems rather than the novel coronavirus re-infecting them.

According to current WHO recommendations on clinical management , covid-19 patients are considered clinically recovered after they’ve tested negative for the virus two days in a row using standard polymerase chain reaction (PCR) testing—aka a throat or nose swab to check for infection. The agency told Reuters that while it was aware of South Korea’s report, it would be conducting additional investigations before determining whether these atypical cases offered new insights about the disease.


“We are aware that some patients are PCR positive after they clinically recover, but we need systematic collection of samples from recovered patients to better understand how long they shed live virus,” WHO said, adding that, “As COVID-19 is a new disease, we need more epidemiological data to draw any conclusions of virus shedding profile.”

Current studies put the virus’s lifespan at around two weeks from when a patient begins exhibiting symptoms such as persistent fever or shortness of breath. If epidemiologists were to discover that covid-19 continues to remain contagious beyond that period somehow, it could affect quarantine timelines and other health measures recommended by public health authorities. Currently, the cause behind this trend of “reactivated” cases remains unknown, WHO told Reuters.

“We are closely liaising with our clinical experts and working hard to get more information on those individual cases,” WHO said. “It is important to make sure that when samples are collected for testing on suspected patients, procedures are followed properly.”



To date, there have been more than 1.7 million confirmed cases of covid-19 cases worldwide, according to researchers at Johns Hopkins, and the virus’s death toll surpassed 100,000 this week.