Certain lingering respiratory symptoms are signs that a patient recovering from COVID-19 still may test positive for SARS-CoV-2, a new study suggests.

Investigators monitored 131 hospitalized patients admitted to post-acute care following a bout with COVID-10. A new RT-PCR test was administered at the time of admission. 

Almost 17% of patients who were considered fully recovered tested positive for the virus in follow-up screenings. And patients who were most likely to have a new positive test result were those with sore throat and rhinitis (chronic sneezing or a congested, drippy nose), reported lead author Francesco Landi, M.D., Ph.D.

“Clinicians and researchers have focused on the acute phase of COVID-19, but continued monitoring after discharge for long-lasting effects is needed,” said Landi, of Agostino Gemelli University Hospital Foundation IRCCS and Catholic University of the Sacred Heart, Rome.

“Our findings indicate that a noteworthy rate of recovered patients with COVID-19 could still be asymptomatic carriers of the virus,” Landi added. The question remains whether the persistent presence of virus fragments means these patients are still contagious, he said. 

When patients exhibit these symptoms, it is reasonable to be cautious by avoiding close contact, wearing a face mask, and possibly repeating a nasopharyngeal swab,” the researchers concluded.

The study was published in the American Journal of Preventive Medicine.