The time is approaching midnight, and the city gradually becomes silent, but people are still queuing up in many 24-hour nucleic acid testing sites in Beijing waiting for testing. Why do they come to test nucleic acid so late?

The reporter visited the 24-hour nucleic acid testing sites of Beijing Chuiyangliu Hospital and Beijing You'an Hospital late at night to listen to their stories.

Responsible editor: [Luo Pan]