False-positive results of nucleic acid test after vaccination may occur, and it is recommended that nucleic acid test be conducted 48 hours after vaccination. At present, the neocoronavirus vaccine injected in China is mainly composed of inactivated neocoronavirus. Although the virus has been inactivated, nucleic acid fragments of the virus are still present in the vaccine. In the course of vaccination, when medical personnel are dispensing, extracting and venting the vaccine, the nucleic acid fragments of the virus may contaminate the environment in the form of aerosols, which may be inhaled into the respiratory tract if the vaccinated person does not wear a good mask, leading to false-positive nucleic acid test results. Therefore, the nucleic acid test immediately after vaccination may show false positive results. It is recommended to clean oneself in time after vaccination and perform nucleic acid test 48 hours later, and at the same time, wear a good mask to protect oneself during vaccination and observation.