In which year did nucleic acid sampling begin in Shenzhen?

Nucleic acid sampling in Shenzhen began in 2019. According to data from the Shenzhen Municipal Government, nucleic acid sampling in Shenzhen began in 2019. Shenzhen has issued guidelines for setting up convenient nucleic acid sampling points. According to the standard of setting up one convenient nucleic acid sampling point for every 30,000 people, more than 700 sampling points have been deployed throughout the city.