Legal basis: Announcement of the Civil Aviation Administration of China and the General Administration of Customs of the People's Republic of China on Filling in Epidemic Prevention and Health Information for China Passengers before Returning to China by Flight Article 1 Since April 8, 2020, passengers who have purchased tickets must go through the WeChat applet of the International Epidemic Prevention and Health Code in advance and fill in personal information, health status, recent travel situation and other information every day. Special circumstances can be filled in by others.