Researchers in Hong Kong recently reported evidence of a person who got the coronavirus a second time, months after an initial infection.The finding has not yet been published in a journal.
But scientists said the 33-year-old man had mild symptoms the first time and none the second time, suggesting his immune system may have provided some protection against serious illness even if it could not prevent a reinfection.
His more recent infection was detected through screening and testing at the Hong Kong airport, and researchers said genetic tests revealed different strains of the virus.Several other possible cases have been reported, including a U.S.