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A growing number of recovered coronavirus patients in China continue to test positive for the deadly bug, according to reports.

Doctors in Wuhan, where the outbreak emerged in December, say the patients all tested negative for COVID-19 at some point during their recovery — but then began testing positive again without showing symptoms as much as 70 days after being cleared.

Chinese officials have not released numbers on how many coronavirus patients are part of the phenomenon, but data from Chinese hospitals obtained by Reuters and other media outlets suggest there are at least dozens.

So far, there have been no confirmations of newly positive patients infecting others, according to Chinese health officials.

The prospect has sparked concerns among health officials in other countries, however, where similar reports have surfaced as countries seek to end lockdown measures — casting doubt on the globally recommended 14-day quarantine period after exposure.

In South Korea, about 1,000 people have reportedly tested positive for four weeks or more, while officials in Italy found that patients could test positive for over a month.

In Wuhan, doctors have responded by keeping patients in isolation longer as a precaution, despite the emotional impact it could have — another concern in a country already ravaged by the deadly global pandemic.

“When patients have this pressure,” said Zhang Dingyu, president of Jinyintan Hospital in Wuhan, “it also weighs on society.”

The plight of Wuhan’s long-term patients underlines how much remains unknown about COVID-19 and why it appears to affect different people in different ways, Chinese doctors say.

“We did not see anything like this during SARS,” Yuan Yufeng, a vice president at Zhongnan Hospital in Wuhan, told Reuters, referring to the 2003 severe acute respiratory syndrome outbreak that infected 8,098 people globally, mostly in China.

So far, global COVID-19 infections have topped 2.5 million with over 179,000 deaths, according to Johns Hopkins University.

With Post wires