Since the release of the 20 measures to further optimize the prevention and control work, various regions have taken various measures to implement them in detail, and concentrated their efforts to fight the epidemic situation in key areas. To improve the effectiveness of epidemic prevention, how can nucleic acid detection "neither add code layer by layer nor reduce code at will"? How to carry out diagnosis and treatment according to different levels and classifications when there is a cluster epidemic in some areas? What is the new progress of orderly promotion of new coronavirus vaccination? Relevant experts of the joint prevention and control mechanism of the State Council made authoritative responses to hot issues of public concern. Question 1: Scientifically and accurately organize nucleic acid detection, how to achieve "neither adding code layer by layer nor randomly reducing code"? A: The ninth version of the prevention and control plan and the twenty optimization measures have made clear provisions on the normalization of nucleic acid testing and regional nucleic acid testing after the outbreak of the local epidemic, requiring all regions to scientifically and accurately organize nucleic acid testing based on the risk of the epidemic. The first is the requirements for normal nucleic acid detection. In areas where there is no epidemic situation, it is mainly to strictly implement the nucleic acid testing requirements for risk posts and key personnel, so as to ensure that all nucleic acid testing should be done to ensure high quality and meet the frequency requirements, and it is not allowed to ignore or miss the testing at will. However, the scope of nucleic acid detection cannot be expanded without authorization. Second, the regional nucleic acid testing requirements after the outbreak of the local epidemic. After the outbreak of the local epidemic, on the basis of epidemiological investigation, the population size of the epidemic area, whether the source of infection is clear, whether the community transmission risk exists, whether the transmission chain is clear and other factors should be comprehensively studied and judged to determine the corresponding nucleic acid detection scheme. Third, the relevant requirements for checking nucleic acid test certificates in public places. In order to effectively prevent the spread of the epidemic, the trans regional floating personnel shall take the aircraft, high-speed railway, train, trans provincial long-distance passenger bus, trans provincial passenger ship and other means of transportation with the negative nucleic acid test certificate within 48 hours. After arriving at the destination, they shall carry out "landing inspection" according to the territorial requirements. Personnel who check in hotels and enter tourist attractions need to check the health code and the negative nucleic acid test certificate within 72 hours. Special populations such as infants and children under 3 years of age may be exempted from checking negative nucleic acid test certificates. The "landing inspection" for trans provincial floating personnel refers to the nucleic acid testing service provided by setting up nucleic acid sampling points in airports, railway stations, long-distance passenger stations, provincial service areas of highways, ports and other places in accordance with the principle of "voluntariness, free of charge, immediate access and unrestricted mobility". The "landing test" does not contradict the requirement of national mutual recognition of nucleic acid test results. Problem 2: Among the 20 optimization measures, it is proposed to formulate a new scheme for the classification and diagnosis and treatment of coronary pneumonia. How to understand "hierarchical classification"? Does this mean that the diagnosis and treatment of patients with new coronal pneumonia should be classified in the future? A: Among the 20 optimization measures, it is very important to strengthen the construction of medical resources, including the development of hierarchical and classified diagnosis and treatment plans and the increase of treatment resources. Since the outbreak of the epidemic, our country has carried out graded and classified treatment for patients by strengthening the capacity building of designated hospitals, shelter hospitals and fever clinics: the purpose of strengthening the construction of designated hospitals is to mainly treat patients with severe, critical diseases and severe tendency. This requires all localities to designate hospitals with strong comprehensive capacity and high treatment level as designated hospitals. Designated hospitals should allocate sufficient treatment beds according to the local population size. At the same time