If a person, who was treated for coronavirus and he doesn’t have any symptoms, don’t be sure that he is completely healed as researchers have found that few numbers of patients they treated for mild COVID-19 infection still carried the virus for up to eight days after symptoms disappeared.
Amid the fast-spreading pandemic, researchers suggest that patients should be quarantined for at least two more weeks even after recovery to be on the safer side.
A study, published in the American Journal of Respiratory and Critical Care Medicine, researchers picked 16 patients, with a median age of 35.5 years, with virus who were treated and released from the Treatment Center of PLA General Hospital in Beijing between January 28 and February 9.
“The most significant finding from our study is that half of the patients kept shedding the virus even after resolution of their symptoms,” said Lokesh Sharma, study co-lead author, Yale University in the US. “More severe infections may have even longer shedding times,” he added.
Researchers collected samples from patients’ throat swabs from all patients on alternate days and analysed. Patients were discharged after their recovery and confirmation of negative viral status by at least two consecutive polymerase chain reaction (PCR) tests.
The study suggested that the primary symptoms in these patients included fever, cough, pain in the pharynx (pharyngalgia) and difficult or laboured breathing (dyspnea). Patients were treated with medications.
The study also indicated that the time from infection to onset of symptoms (incubation period) was five days among all but one patient.
The average duration of symptoms was eight days, while the length of time patients remained contagious after the end of their symptoms ranged from one to eight days.
Two patients had diabetes and one had tuberculosis, neither of which affected the timing of the course of the infection.
“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,” suggested corresponding author Lixin Xie from Chinese PLA General Hospital in China.
The authors had a message for the medical community: “COVID-19 patients can be infectious even after their symptomatic recovery, so treat the asymptomatic/recently recovered patients as carefully as symptomatic patients.”
The researchers further emphasised that all of these patients had milder infections and recovered, and that the study looked at a small number of patients.
They noted that it is unclear whether similar results would hold true for more vulnerable patients such as the elderly, those with poor immune systems and patients on immunosuppressive therapies.
“Further studies are needed to investigate if the real-time PCR-detected virus is capable of transmission in the later stages of COVID-19 infection,” Xie added.