WUHAN -- Medical research and clinical observations supported a fact that patients recovering from COVID-19 are no longer infectious and can return home safely, a Chinese doctor said on Saturday.

Cheng Zhenshun, director of the department of respiratory and critical care medicine of Zhongnan Hospital of Wuhan University, said cured patients must conform to certain criteria for hospital discharge and undergo a 14-day observation before being able to go home.

The criteria include normal body temperature for more than three days; respiratory symptoms improved significantly; pulmonary imaging showing significant absorption of acute exudative lesions; sputum and nasopharyngeal swabs and other respiratory tract specimens tested negative in two consecutive nucleic acid tests, with the sampling time at least 24 hours apart.

"The discharge criteria not only conform to the treatment principle of pneumonia but also accord with the management requirements of respiratory infectious diseases," said Cheng.

Discharged patients are also required to undergo a 14-day medical observation at isolation sites and receive nucleic acid testing again before they return home, added Cheng.

He said the rigorous and science-based procedure can assure the safety for the patients to return to normal life.