The 60-year career of Hou Yunde, a global authority on viruses who is known as the guardian of China's health, is still inspiring medical professionals around the world, as Zhang Zhihao reports.

In the summer of 2014, during an outbreak of Ebola in Sierra Leone, West Africa, four Chinese healthcare professionals spent days in a stiflingly hot biosafety lab the size of two shipping containers checking blood samples for evidence of the virus, one of the deadliest pathogens in history.

"It was the first time our team members had dealt with such a terrifying virus in such horrific sanitary conditions," said Wu Guizhen, Party secretary of the National Institute for Viral Disease Control and Prevention at the Chinese Center for Disease Control and Prevention.

During transportation of the samples, bloodstained needles and broken glass penetrated some of the containers and occasionally sliced through the Chinese doctors' gloves. "If they had punctured the skin, the person would probably have died. We really handled death with our fingertips," Wu said.

Seventy members of staff from the center traveled to West Africa during the 2014 outbreak to provide aid.

"They all wrote farewell letters to their families (to be delivered in the event of their deaths). But they still wanted to go to help those in need and to make Hou Yunde, their mentor, proud," Wu said.

For more than six decades, Hou has been a bulwark against viruses and contagious diseases in China, and he is an inspiration to health workers, she added.