1 class: outpatients with fever; The second category: close contacts; The third category: overseas entry personnel; The fourth category: staff in designated hospitals and fever clinics; Category V: port quarantine and frontier inspection personnel; The sixth category: centralized isolation of staff in medical observation places; Seventh category: close contacts of close contacts; Category 8: people who should return from medium and high-risk areas; Category 9: new inpatients and caregivers; Category 10: staff of other medical institutions; Category 1 1: employees who are in direct contact with frozen and refrigerated cold chain food; Category 12: management objects or service objects and staff of supervision places, welfare institutions and pension institutions; Category 13: workers in closed or crowded places (farmers' markets, airports, stations, docks, public transportation, travel agencies and tourist attractions, libraries, gymnasiums, theaters, labor-intensive enterprises, etc.). ); Category 14: key population designated by the municipal prevention and control headquarters.

For 1 population, the "single test" method is used for nucleic acid detection; The group of 2-8 people detected nucleic acid 1 time every 7 days, and the nucleic acid detection adopted the "single detection" mode; 9- 1 1 population detects nucleic acid every 14 days/time, and nucleic acid detection adopts "single detection" method; 12- 13 class personnel conduct nucleic acid testing once a month, with "single test" for the first time and "mixed test" for 10 class; 14 personnel are determined by the municipal prevention and control headquarters according to the actual situation.