WUHAN, China — In the mornings, Wuhan is so quiet that bird calls sound down once busy streets. Stray dogs trot in the middle of empty expressways. Residents wrapped in masks creep out of their homes, anxiety flitting across their eyes.

They line up at hospitals overwhelmed by a virus that most had not heard of until a few weeks ago.

They line up outside pharmacies despite the door signs declaring they have sold out of protective masks, disinfectant, surgical gloves and thermometers. They line up to buy rice, fruit and vegetables from food stores that keep operating, while nearly all other shops are closed.

Then they shuffle home to wait out this 21st-century siege. The unluckiest ones lie at home or in a hospital, stricken by pneumonia fevers that could spell death linked to coronavirus 2019-nCoV.

“I’d never heard of this thing called a coronavirus before,” said Sun Ansheng, a man in his 50s who the other day was sitting on the steps outside Hankou Hospital in Wuhan, where his feverish wife was being treated as a suspected victim of the coronavirus. “But now it’s in my mind as soon as I wake up.”