Generally, the health code passing through epidemic areas at high speed will not change color, and the discoloration of health code mainly refers to the discoloration of places where people live or have been.
If you just drive through a high-risk epidemic area, all the way at high speed, without stopping, the health code will generally not change color. If you have been to the epidemic area for more than two hours, or have been in contact with confirmed cases, the health code may change color. The main reason for the discoloration of health code is the contact with newly diagnosed cases or asymptomatic infected people, including close contacts, secondary close contacts and close contacts with time and space.