Legal Analysis: The Prevention and Control Plan of novel coronavirus (5th Edition) puts forward the classification of epidemic risk according to the Law of People's Republic of China (PRC) on the Prevention and Control of Infectious Diseases and the Emergency Regulations of Public Health Emergencies, aiming at implementing accurate prevention and control by districts, scientifically dividing the epidemic risk level, and clarifying the prevention and control strategies by classification on the basis of comprehensively judging the population and incidence. Medium-risk area: there are newly confirmed cases within 14 days within the administrative area, and the cumulative confirmed cases are no more than 50; Or the cumulative number of confirmed cases is more than 50, and no cluster epidemic has occurred within 14 days. High-risk area: there are more than 50 confirmed cases in this administrative area, and a cluster epidemic occurs within 14 days.

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

Article 26 The State shall establish a database of strains and viruses of infectious diseases. The collection, preservation, carrying, transportation and use of infectious virus strains, viruses and infectious disease detection samples should be classified and managed, and a strict management system should be established and improved. If it is really necessary to collect, preserve, carry, transport and use strains and viruses that may lead to the spread of Class A infectious diseases and infectious disease samples specified by the health administrative department of the State Council, it must be approved by the health administrative department of the people's government at or above the provincial level. The specific measures shall be formulated by the State Council.

Twenty-seventh sewage, dirt, places and articles contaminated by infectious disease pathogens, the relevant units and individuals must be strictly disinfected under the guidance of disease prevention and control institutions or in accordance with their hygiene requirements; Refuse to disinfect, by the local health administrative department or disease prevention and control institutions for compulsory disinfection.

Twenty-eighth plans to build water conservancy, transportation, tourism, energy and other large-scale construction projects in natural foci confirmed by the state, the disease prevention and control institutions at or above the provincial level shall conduct hygienic investigation on the construction environment in advance. The construction unit shall, according to the opinions of the disease prevention and control institutions, take necessary measures to prevent and control infectious diseases. During the construction period, the construction unit shall designate a special person to be responsible for the health and epidemic prevention work on site. After the completion of the project, the disease prevention and control institutions shall monitor the possible infectious diseases.