Han Jie, which used to be Wuhan's busiest commercial center, is all but empty.

But there's a bubble tea shop, perhaps the only one in town, that's still open but only to medical workers.

The shop makes 300 cups of bubble tea every day and 300 more are sent to Wuhan Union Hospital every Saturday. And they're all free.

Ten volunteers, mostly in their 20s, work on two shifts to make bubble tea and bread.

They don't have private cars and public transportation in the city is closed.

For 22-year-old Ye Mengyi, it means she has to walk hours every day.

Ye told CGTN, "If I had a bike, it would take me around 30 minutes to get to work. But on foot, I have to walk more than an hour."

In this battle against the virus, more than 1,100 medical workers are infected in Wuhan, a city now of more than 9 million people.

Chen Juntong, a 25-year-old baker, hopes he can do something for the medical staff. "With all the people in self-isolation at home, only the medical workers can choose to stand up against the virus. But they're also human. They have fears. I hope they could feel some warmth in their busy work."

For Yang Min, 35, working here is proof her city is still alive. "Despite the lockdown in Wuhan, what we do here makes me feel like my city hasn't stopped. It's still moving, but just slowly."

As the whole city is on lockdown, couriers are among the main contributors to keep the city running. 

Having followed the couriers to a logistics center, a nurse shared her experience with CGTN. 

Chen told us that the SF Express has provided lots of help in distributing medical goods to hospitals in Wuhan and nearby regions. She added, "The couriers themselves even paid the express fees to send the goods to Jingzhou Central Hospital (200 kilometers away from Wuhan)."

SF Express is one of the three express companies that insist on providing services in towns during the virus outbreak, but only for sending and receiving medical goods.

Shi Zhangbing has been working here since day one of the outbreak.

When asked about whether he envied the couriers of other companies staying at home in this outbreak of the deadly virus, he said: "No. I think they should be envious of us because, despite the epidemic, we stand up and provide service. We feel very proud."

He often has to work in hospitals, risking exposure to the virus.

Shi lives alone in Wuhan while his family lives in a remote village. Every night, he talks to his family via video chat.

"Every time, my son will tell me 'Daddy, I'm so proud of you'. And every time I hear this, I can feel a great relief."

As doctors and nurses race against time to protect the city, the people here are also doing everything they can to support and keep the city going.