Legal analysis: 1. On the basis of the original "four ones" health management, the people who came (returned) to Shenzhen in Nanjing from July 7 to June 13 were tested for nucleic acid again; 2. Carry out home health monitoring on those who came to Shenzhen from July 14 -20 except the airport until they left Nanjing 14, and carry out nucleic acid detection three times in seven days; 3. From July 2 1 day to July 27, except for those who came to Shenzhen from the airport, they were isolated at home until they left Nanjing 14, and their nucleic acids were detected on 1 4, 7 and 14; 4. For those who come (return) to Shenzhen from other ways other than the airport on or after July 28th, centralized isolation for 7 days+home isolation for 7 days, and nucleic acid detection is carried out on 1, 4, 7 and 14 days.

Legal basis: People's Republic of China (PRC) Law on the Prevention and Control of Infectious Diseases.

Article 13 People's governments at all levels shall organize mass health activities, carry out health education on the prevention of infectious diseases, advocate civilized and healthy lifestyles, improve the public's awareness and ability to cope with infectious diseases, strengthen environmental sanitation construction, and eliminate the harm of rodents and vectors such as mosquitoes and flies.

The administrative departments of agriculture, water conservancy and forestry of the people's governments at all levels are responsible for guiding and organizing the elimination of rodents and schistosomiasis hazards in farmland, lakes, rivers, pastures and forest areas, as well as the hazards of other animals and vectors that spread infectious diseases.

The administrative departments of railways, transportation and civil aviation shall be responsible for organizing the elimination of rodents, mosquitoes, flies and other vectors in vehicles and related places.

Article 39 When a medical institution discovers a Class A infectious disease, it shall take the following measures in time:

(a) isolation treatment of patients and pathogen carriers, and the isolation period shall be determined according to the results of medical examination;

(two) for suspected patients, isolation treatment in designated places before diagnosis;

(3) Carry out medical observation and take other necessary preventive measures at designated places for patients, pathogen carriers and close contacts of suspected patients in medical institutions.

The public security organ may assist medical institutions to take compulsory isolation treatment measures if they refuse isolation treatment or leave isolation treatment without authorization before the expiration of isolation period.

Medical institutions should take necessary treatment and control measures according to the condition when they find patients with Class B and Class C infectious diseases.

Medical institutions must, in accordance with the provisions of laws and regulations, disinfect and dispose of places, articles and medical wastes contaminated by infectious disease pathogens in their own units.