It is a notification after screening through big data. Zhengzhou government platform to send text message nucleic acid abnormal through big data screening after the notification of some of the risk of overlap with the trajectory of the infected person to inform, after receiving the information, you can still travel, but need to be in accordance with the requirements of the text message, two nucleic acid test within 72 hours. During this period, travel briefly under the premise of good personal protection (avoid taking public **** transportation, avoid going to crowded places).