The expiration date of a new coronavirus nucleic acid test report is determined by the local authorities. The expiration date is usually within 48 hours or one week. The validity of nucleic acid test results is calculated from the time of sampling, and is valid for one or two days, or one week in some places, and for high-risk areas there is a requirement to have a negative nucleic acid result within 24 hours or 48 hours. For low-risk areas there are provisions to have a negative nucleic acid certificate within a week. A new crown nucleic acid test is required to fight the epidemic and for ease of travel. Try to get the test done earlier before the test report becomes invalid to avoid interfering with normal travel. If positive, isolate and report.