The main reason for doing antigen and nucleic acid once a day is that the new coronavirus has a certain hidden period, and it is not easy to be detected by nucleic acid at the early stage of infection, so doing antigen and nucleic acid once a day can effectively improve the test results. When the new coronavirus infects the human body, the body will produce corresponding antibodies to destroy the foreign new coronavirus as an antigen, so it is possible to detect whether the new coronavirus is infected by doing the antigen test. As for nucleic acid test, it mainly refers to the use of cotton swabs to collect sputum and lower respiratory secretions from patients, and through the fluorescence quantitative PCR technology, to detect whether it carries the nucleic acid of the virus. Since the incubation period of neocoronavirus infection is usually around 3 to 7 days, and since the virus is more insidious, it cannot be detected by a single antigen as well as nucleic acid test, and for people susceptible to infection in medium and high-risk areas, it is necessary to do the antigen as well as nucleic acid test once a day in order to effectively rule out the possibility of being infected with neocoronavirus. It is also effective in screening out neocoronavirus-infected persons with high viral loads for timely isolation to effectively control the spread of the new coronavirus. During the epidemic period, if you have been in contact with infected people and have fever, cough and other symptoms, we recommend that you go to a specialized hospital, identify the cause of the disease and under the guidance of the doctor to carry out the next examination and treatment, and report to the relevant departments to take proper quarantine measures.