Based on the epidemic prevention and control of big data, generally will be given a yellow code to the health code of the people who have recently stayed in the key areas of prevention and control, at this time, will also receive a health code to turn the code of the text message reminder.

If the health code becomes yellow, then there will be some restrictions on travel, so within 72 hours of receiving the health code transfer SMS, you need to go to the nearest temporary sampling point (or medical institution) for two nucleic acid tests, and if the nucleic acid test is negative, then it can be turned into green.