A new study in The Lancet medical journal published Wednesday found that the novel coronavirus lived in the respiratory tracts of some patients for more than five weeks. Some of the patients received antiviral medications but the drugs did not appear to shorten the virus's lifespan.
The 19 doctors who authored the study analyzed the medical records of 191 patients in China (135 from Jinyintan Hospital and 56 from Wuhan Pulmonary Hospital), including the demographic, clinical, treatment and laboratory data of 137 coronavirus patients who were discharged and 54 patients who died in the hospital.
They found that the virus was present in the bodies of patients with severe disease status for an average of 19 days, and inside the bodies of patients with critical disease status for an average of 24 days. Overall, the virus was detected for an average of 20 days in patients who were eventually discharged from the hospital. In the respiratory tracts of patients who died, coronavirus was detectable until death.
The shortest length of time the virus lived in the respiratory tract of a survivor was eight days. And perhaps most shocking of all, in some cases, the virus persisted for as long as 37 days.
"This has important implications for both patient isolation decision making and guidance around the length of antiviral treatment," the authors of the study concluded.
For weeks, the U.S. Centers for Disease Control and Prevention has been advising Americans who traveled to one of the virus's epicenters or who may have been otherwise exposed to self-quarantine for 14 days. Does this study suggest the risk could persist longer? Well, not necessarily.
CBS News medical contributor Dr. David Agus says using this study's findings to extrapolate how long a person might be contagious is probably taking it a step too far.
"This is an important study to understand the medical course of patients who have symptomatic cases of Covid-19 infection," he said in an email. "I would be very cautious to use these data to quantify periods of being infectious. This information has yet to be determined definitively."