Even after people with mild cases of the new coronavirus feel better, new research shows that half still have the virus for up to eight days after symptoms are gone.
That's the conclusion of a small international study of 16 Covid-19 patients in China. The researchers took several throat swabs from all of them.
"The most significant finding from our study is that half of the patients kept shedding the virus even after resolution of their symptoms," said co-lead author Lokesh Sharma, an instructor at Yale School of Medicine in New Haven, Connecticut. "More severe infections may have even longer shedding times."
It took about five days from the time patients were infected until symptoms appeared, and about eight days before they disappeared. Patients were contagious for one to eight days, the researchers said in a news release from the American Thoracic Society.
More research needed
Study co-author Dr Lixin Xie, of Chinese PLA General Hospital in Beijing, advised: "If you had mild respiratory symptoms from Covid-19 and were staying at home so as not to infect people, extend your quarantine for another two weeks after recovery to ensure that you don't infect other people."
Xie and Sharma cautioned doctors that Covid-19 can spread even after symptoms disappear, so patients who have recovered need to be treated as if they're still infected.
Xie said more research is needed to learn whether the virus is capable of transmission in the later stages of Covid-19 infection.
The report was published online in the American Journal of Respiratory and Critical Care Medicine.