Photo:Xinhua

Wuhan, the epicenter of novel coronavirus pneumonia (COVID-19), is requiring all patients discharged from the hospitals to go to designated locations for another 14-day quarantine, as scientists fear the coronavirus may be more "cunning" and difficult to detect than previously expected. 

The epidemic prevention and control center in Wuhan, Central China's Hubei Province, said on Saturday all the recovered COVID-19 patients need to go to designated places for another 14-day medical observation, free of cost.

"The move aims to ensure health and safety of the patients and their family members," Yang Zhanqiu, the deputy director of the pathogen biology department at Wuhan University, told the Global Times on Saturday.

The move has been announced after it was recently found that some patients who appear to have recovered could once again test positive for nucleic acid diagnosis, indicating they still have the virus. 

A patient in Chengdu, Southwest China's Sichuan Province, was discharged from hospital on February 10 and stayed under a 14-day self-imposed quarantine. However, on February 19, the patient was again tested positive for the virus and had to be readmitted into the hospital, according to media reports. 

Test results may also come out different depending on where the samples are retrieved from. For example, nasal or throat swab may test negative while feces test may still come out positive, scientists and epidemiologists have warned. 

Zhao Jianping, a medical team leader in Wuhan, urged to exercise caution when discharging COVID-19 patients, media reported Wednesday. "I have a patient who recovered but got infected again after discharge," Zhao said, noting that a few days later, the patient had a fever and the nucleic acid tested positive, which could become an infection source contaminating other individuals.

Global Times