Lacey, did you get the space-time message?

The news from the epidemic prevention and control headquarters was told that it appeared at the same time as the confirmed cases in COVID-19, and it was required to complete two nucleic acid tests within 72 hours from the date of receiving the news, and to avoid taking public transportation. If the nucleic acid has not been made within the time limit, it will be given a yellow code and managed according to the relevant epidemic prevention and control policies.

Spatio-temporal companion refers to the person who stays with the diagnosed patient for 14 days 10 minutes in the same spatio-temporal grid (usually 800 m× 800 m as the detection range). In layman's terms, for example, an infected person has been to a place within 14 days, and the trajectory of your 14 days intersects with him. Whether it is a physical brush or a drift in communication signals, it may be considered as a problem of time and space. Experts said that screening "time-space companions" can find potential risk groups to the greatest extent, and include more people who are "time-space overlapping" and may be infected in key investigations, so as to truly achieve early detection and early prevention and control.