Surrounded by a crowd of anxious COVID-19 patients in a tiny room in a Wuhan clinic, doctor Zhang Boli could sense their fears－as well as hopes－just by looking at them.

It was late January last year, and China was celebrating the Spring Festival. Zhang, head of the Tianjin University of Traditional Chinese Medicine, had rushed to Hubei province on Jan 27 as he was worried about the risk of cross-infections from the virus.

As a member of the Communist Party of China and an academician of the Chinese Academy of Engineering, he said he felt an enormous duty to volunteer for the front line.

He immediately warned his colleagues the patients should not be crammed together in such close conditions.

With no effective medicine yet for the virus, Zhang proposed that the patients should be classified into four groups: those confirmed with COVID-19; those with an apparent fever; those with suspected symptoms; and those who needed to undergo observation after coming into close contact with infected people.