2. Incubation period: The incubation period of the new coronavirus is 3-7 days, if the infected person belongs to the incubation period, the nucleic acid test result will be negative, it is recommended to conduct two or more tests, if the result is still negative, it can be determined that the new coronavirus is not infected. If the result is positive, the patient should be isolated immediately for treatment. 3. Personal physical reasons: If the patient has nausea, vomiting and other symptoms during sampling, it may interfere with the nucleic acid test result and give a false negative result. False negative, such patients are recommended to recover from the disease before testing; 4, improper operation of the test: if the test personnel improper operation or machine failure, there will also be false negative results, then you should re-test the nucleic acid test or wait for the machine to recover before testing. It is recommended to do 3 consecutive nucleic acid tests if possible, so as to avoid various interfering factors and prevent false negatives. If the test is negative three times, it generally means that the results are normal and the patient is not infected with the new coronavirus.