A negative nucleic acid test for fever does not completely exclude the possibility of infection with the new coronavirus; it is necessary to rule out the possibility that the nucleic acid test is false-negative or that the low viral replication is currently undetectable, and it is necessary to combine this with the epidemiologic history and other comprehensive judgments. Fever is one of the typical symptoms of neocoronavirus infection. If a patient has fever after exposure to a patient who is positive for the new coronavirus, then nucleic acid testing should be done promptly. If the nucleic acid test is negative, the possibility of infection with the new coronavirus cannot be ruled out in time. If false negatives are ruled out, it is also possible that neococcal pneumonia may have a low level of viral replication just after infection, and the nucleic acid test may still be negative. At this point, the need for retesting should be determined in conjunction with the epidemiologic history. It is recommended that patients with fever should go to the hospital for symptomatic treatment under the guidance of the doctor and take care of rest. Repeat nucleic acid testing is also required if there is a relevant epidemiologic history. Tips] In this article, “new coronary pneumonia, new coronary virus pneumonia” has been renamed to “new coronary virus infection” on December 26, 2022, as announced by the National Health Commission.