Some recovered patients discharged from the hospital have tested positive for the novel coronavirus, but so far they haven't been found to be infectious, an official with the National Health Commission said on Friday.

A discharged patient waves to medical staff at Leishenshan Hospital in Wuhan, Central China's Hubei province, on Feb 27, 2020. (Photo: China Daily)

Among these patients, some have turned negative in following tests, Guo Yanhong, an official with the commission's Bureau of Medical Administration, told a news conference in Beijing.

She said health authorities would put newly-released patients on 14-day medical observation and step up tracking and research on them.

For this new coronavirus, much more needs to be learned about it including pathogenic mechanisms and the course of the disease, she added.