At present, the health code in Zhengzhou city turns red or yellow mainly because of the close and sub-close connection of staying in foreign or local high-risk areas, recent entry, staying in key areas or confirmed cases.
According to the comprehensive analysis of big data, the risk level of epidemic prevention and control is given three color health codes: red, yellow and green. At the same time, for some key personnel who fail to carry out nucleic acid testing as required within the time limit, the health code will also be changed to red code or yellow code.