In spite of antibodies in the system, patients who recover from the novel coronavirus may be infected again if they don't take precautionary measures, a senior medical expert said.

Antibodies will be generated in those infected by the virus to protect their bodies, but it may not last long, Zhan Qingyuan, head of an expert team for pneumonia control at China-Japan Friendship Hospital, said at a news conference on Friday.

"Those who have recovered are still confronted with the risk of being infected and should take strengthened precautionary measures," he noted.

Zhan also dismissed concerns that the disease will leave sequela in all those infected.

There should be no sequela for patients with mild symptoms. For those with severe symptoms, they may experience pulmonary fibrosis, he said.

He added, however, most of the problems will be addressed thanks to the ability of the lung to repairing itself, though symptoms may linger for an extended period of time in a tiny minority of patients with extremely severe cases.

Some patients may experience depressive disorders after they are cured. They should visit psychologists to relieve themselves if necessary, he said.

He also suggested all those cured visit doctors regularly to have their lungs checked.

According to the National Health Commission of China, 171 people on the Chinese mainland have been released from hospitals after recovering from the novel coronavirus-caused pneumonia as of Thursday at midnight.

The commission also said 9,692 had been infected by the virus, and the death toll has reached 213.