The serum test for Neocollins checks for IgM and IgG antibodies, with normal values ranging from 0 to 1 g/L. Exceeding 1 g/L indicates a positive antibody test, which can be combined with nucleic acid testing for further diagnosis. Neoguana serum test antibodies are usually produced after infection with Neoguana virus or vaccination against Neoguana. positive IgM antibodies indicate the presence of acute-phase infection, which is contagious and requires isolation. Positive IgG antibodies only indicate the presence of a previous infection. Positive serum antibodies may be due to vaccination and need to be combined with nucleic acid testing to determine the presence of neocoronavirus infection. Due to differences in testing methods and reagents among testing organizations, the corresponding normal value ranges may vary. In addition, the serologic test alone is not diagnostic, but should be combined with epidemiologic history, clinical manifestations, and nucleic acid test results to determine the presence of neocoronavirus infection. There is no need to be overly anxious if the new coronavirus serum antibody is positive, as it can be caused by vaccination or previous infections. If it is caused by a recent viral infection, it is important to actively cooperate with the quarantine of the epidemic control and further improve the relevant examinations, and comply with the doctor’s instructions for treatment.