In general, the administration of New Crown vaccine does not affect the detection of viral nucleic acids and can be performed at any time. However, if the New Crown vaccine administered is an inactivated virus vaccine, it is best to wait 1-2 days before performing nucleic acid testing. Inactivated virus vaccine contains the nucleic acid sequence of the virus, and in the process of administering New Crown vaccine, the vaccine may contaminate the vaccination site, the vaccination personnel and the vaccine recipient directly or indirectly by extracting the vaccine and exhausting the syringe in liquid or aerosol form, resulting in the presence of New Crown virus nucleic acid fragments in the nasal or throat mucosa of the vaccine recipient, and in the detection of New Crown nucleic acid in nasopharyngeal secretions False-positive results may occur. After 1-2 days of testing, the nucleic acid fragments of the new coronavirus can be excreted with the nasopharyngeal secretion, and the residual nucleic acid fragments will be greatly reduced and will not appear as false positives. If the vaccination is a recombinant vaccine or an adenovirus vector vaccine does not contain the nucleic acid sequence of the virus, it usually does not contaminate the environment or the vaccine recipient. The timing of viral nucleic acid testing is not limited by the time of vaccination with the new crown vaccine, and testing can be performed at any time. However, because some populations are more specific, such as those who have traveled to medium and high-risk areas and are at risk of virus infection, timely nucleic acid testing is required according to national policy and should be explained to the healthcare provider and tested under the guidance of a physician.