Connect the two types of risk area delimitation standards and prevention and control measures, unify the use of the concept of medium and high risk areas, and form a new risk area delimitation and control plan. The high-risk area implemented "door-to-door service". No new infections were reduced to stroke risk areas for 7 consecutive days, and no new infections were reduced to low risk areas for 3 consecutive days. In other areas, centralized isolation medical observation measures were taken for persons with a history of living in high-risk areas in the past 7 days. The stroke risk area implemented "no foot out of the area, wrong peak extraction", and no new infection was reduced to a low risk area for 7 consecutive days.