As the number of new cases of coronavirus are increasing globally, about 10 percent of recovered patients of coronavirus in China have test positive again after being discharged from the hospital.
According to news agency ANI,doctors from Tongji hospital on the frontlines of the outbreak in Wuhan--where the virus emerged--told state broadcaster CCTV that they have found no evidence that these patients who again tested positive became infectious.
The Chinese mainland, where the disease first emerged last December, has discharged over 90 percent of its infected patients and around 4300 confirmed patients are still recieving treatment in hospital.
The country has reported at least 81,000 cases and more than 3,200 deaths, but most of the new cases have been confirmed.
The hospital confirmed that five of 147 patients--only over 3 to 5 percent--tested positive agains in nucleic acid tests, according to state broadcaster CCTV.
"So far there is no evidence to suggest that they are infectious," said Wang Wei, the hospital's president.
He said the five patients who tested positive again did not have any symptoms and none of their close contacts had been infected.
In spite of its relatively small sample size, the research of the Tongji hospital, which identified the first COVID-19 case, is especially relevant as China now has far more recovered patients than news confirmed cases.
Wang added that surveillance of similar patients showed that 80 percent to 90 percent had no trace of the virus in their system one month after being discharged from the hospital, according to the report.
But, he said, these are just "small samples" and "not enough to assure us of the validity of our initial findings."
The hospital's president said: "We need a large -scale epidemiological study to guide our disease surveillance and preventive works."
Researchers around the world are trying to determine whether recovered patients can still infect people with the coronavirus that causes the disease and if they have developed antibodies offering them immunity to the diseases.
Manwhile, other quarantine facilities in Wuhan have seen about 5 percent to 10 percent of their recovered patients test positive again. The findings were reported by the health news outlet Life Times, which is affiliated which state-run newspaper People's Daily.
The studies come as health officials around the world are testing the concept of taking plasma from someone who has been infected, processing it and injecting the antibodies into a sick person to stimulate their immune system.
(With inputs from ANI)