SEOUL—More than 160 South Koreans have tested optimistic a 2nd time for the coronavirus, a development that indicates the sickness may perhaps have a for a longer time shelf existence than envisioned.

Quite a few experienced volunteered for re-examination after exhibiting signs these kinds of as coughing. Other individuals submitted to excess tests on minimal much more than a hunch inspite of not exhibiting signs. So far, these patients—all of whom desired to 2 times take a look at destructive before leaving clinical supervision—haven’t unfold the virus to other individuals, community overall health officials say.