Of the patients who have recovered from Covid-19 and discharged from hospitals in China’s Guangdong province, 14 percent were tested positive again at later check-ups, says local health authorities, according to Chinese daily Caixin Global.
In a report earlier today, Caixin Global noted that the positive tests may suggest that the recovered patients still carry the virus. This makes containing the outbreak more complex.
Song Tie, deputy director of the Guangdong Centre of Disease Control And Prevention (Guangdong CDC), said at a briefing on Tuesday (25 February) that there is no clear conclusion as to why this could happen or whether these patients are still infectious.
Preliminary assessments show that experts think these patients have not fully recovered from lung infections, said Song.
The latest treatment guidelines for Covid-19 by China’s National Health Commission says patients can be considered as recovered and be discharged from the hospital when their nose and throat swabs turn up negative in two consecutive tests, a CT scan showing no lung lesions, and when they no longer have obvious symptoms like fever.
The guidelines also say that these recovered patients should monitor their health and limit outdoor activities for 14 days after being discharged. They should also report back to a hospital for retesting in the following weeks.
It is during this retesting at follow-up checks that some of the recovered patients’ results turned up positive, said Li Yueping, director of the intensive care unit at Guangzhou No.8 People’s Hospital, at the same briefing.
The hospital confirmed that 13 of its discharged patients tested positive for Covid-19 again, though none of them showed symptoms. Additionally, the nucleic acid tests for 104 of their close contacts all turned up negative, said Li.
Director of the Infectious Diseases Division at No.8 People’s Hospital Cai Weiping noted that the positive results in the recovered patients were from anal swabs, a test that is rarely employed in other parts of China. Cai added that these results were in the range of ‘weak positive’.
China’s national treatment guideline only requires suspected patients to be tested from throat or nose swabs because it is believed that the virus spreads mainly via respiratory droplets, produced when someone coughs or sneezes.
However, researchers at Guangzhou Medical University found the virus in fecal samples as well, possibly indicating another transmission path. Following this discovery, several hospitals in the province have adopted anal swabs when testing for the virus.
Cai noted that it is still unclear whether the virus detected in these recovered patients are still active, adding that there is also a possibility of discrepancies in the samples.
Guangdong CDC’s Song explained that the province is preparing to place those recovered patients who tested positive under a concentrated observation. He added that health authorities will also ramp up monitoring of discharged patients and their health as they recovered.
As of Monday (24 February), Guangdong reported 1,347 infections, 805 recoveries, and 7 deaths. Nationally in China, there are now 77,770 confirmed cases and 2,666 deaths since the outbreak emerged.
In a different province, Sichuan, a patient in Chengdu city also retested positive after being initially discharged.
In the province of Hainan, local health authorities confirmed the same scenario of recovered patients testing positive for the virus again. There, local authorities imposed a 14-day home quarantine on discharged patients, lifting the quarantine only after both throat and anal swab tests come back negative for the virus.