Two nucleic acid tests can be done within 24 hours, but it is not recommended to do two nucleic acid tests within 24 hours. Nucleic acid test is a means of testing the secretions from the mucous membranes of the throat and nasal passages as well as blood and feces of the person being tested as specimens to determine whether or not they are infected with a virus. Examples include the new coronavirus nucleic acid test and the hepatitis B virus blood test. If two nucleic acid tests are done within 24 hours, the results of both tests can usually be shown, but this is not recommended. This is because there is a certain interval in viral replication. If two nucleic acid tests are done within 24 hours, the interval is too short, and a certain degree of false negatives may occur, which may lead to misdiagnosis of the results. If the new coronavirus nucleic acid test is done, it is not recommended to eat stimulating food half an hour before the nucleic acid test, so as not to cause vomiting, nausea and other uncomfortable symptoms. After the test, you should leave the test site immediately and avoid staying in the crowd for a long time.