1.Blood picture Total leukocytes decreased, lymphocytes increased relatively, eosinophils disappeared, when combined with bacterial infection, total leukocytes and neutrophils increased. 2.Immunofluorescence or immunoenzymatic staining method to detect antigen Take the patient’s nasal washings in the mucosal epithelial cells of the smear specimen, with fluorescent or enzyme-labeled influenza virus immune serum staining to detect antigen, out of the results quickly, high sensitivity, help early diagnosis, such as the application of monoclonal antibodies to detect anti-principles can identify influenza A, B, C. 3, multiplex enzyme chain reaction (PCR) determination of influenza virus RNA It can be directly from the patient’s secretions to detect viral RNA, is a direct, rapid, sensitive method, the current improved application of PCR – enzyme beam (PCR-EIA) direct detection of influenza virus RNA, it is much more sensitive than the virus culture, and rapid, direct determination. 4.Virus isolation The virus is isolated by inoculating the gargle-containing fluid of the patient in the acute stage into the chicken embryo amniotic sac or urinary bladder fluid. 5.Serological examination Application of hemagglutination resistance test, complement binding test, etc. to determine the antibodies in the serum in the acute and recovery period, if there is more than 4-fold increase, it is positive, application of neutralization immunoenzyme test to determine the neutralization titer, can detect neutralizing antibodies, these are helpful for retrospective diagnosis and epidemiological investigation. 6, PCR detection of influenza virus gene Since all influenza virus genome of each RNA segment of the 5 end and 3 end are conserved, so can be designed according to the synthetic primers, PCR detection. PCR technology can be directly from the patient’s secretions to detect influenza virus gene, than the virus culture method is sensitive, fast; but it should be noted that false positives can occur, and those who appear myocardial damage, manifested as abnormalities of the electrocardiogram.