Jin Yujuan's job is like opening a Pandora's box.

The head of the pathogen laboratory of the disease control center of Shenzhen's Longgang District and her colleagues are responsible for testing samples from suspected coronavirus cases. They have kept working around the deadly virus since mid-January when the first suspected case was found in the district.

In the sealed-off labs filled with the acrid smell of disinfectant, the laboratory employees, with all protective gear on, remove the heavy parcel covering the cells containing samples from suspected patients, open the cell and isolate the nucleic acid. ''Every single step is like removing a time bomb," Jin said.

The most important step is isolating nucleic acid from the virus. Usually two people work together on this to prevent the virus from ''escaping''.

''Each of us is likely to fall victim to the virus if there is anything wrong with the isolation,'' Jin said. She and her colleague isolated the first Nam Dinh virus strain in the nation and the second in the world in 2012.

For the past month during the epidemic control nationwide, Jin's lab has tested on average 70 samples every day, with as many as 130 in the peak period.

''The nucleic acid testing provides a guide to epidemiological studies and suspect case screening. We must act quickly to remove the 'time bomb'," Jin's colleague Yang Hui said.