[Use of a method of molecular nucleic acid hybridization for the rapid diagnosis of influenza].

A highly sensitive method of pinpoint hybridization of nucleic acids on nitrocellulose filters using 32P-labeled pHA plasmid carrying a DNA copy of hemagglutinin gene of influenza A/Udorn/307/72 (H3N2) was developed which permitted specific detection of minimal amounts of RNA (units of pikograms) of influenza A virus with H3 serotype hemagglutinin. The method of pinpoint hybridization was used for the detection of RNA of influenza A (H3 serotype) in nasopharyngeal washings of patients with acute respiratory diseases during the influenza outbreak of February-March, 1984. In parallel, the presence of viral antigen was determined by direct immunofluorescence using H3N2 antiserum, and the diagnosis of influenza was confirmed by the clinical picture of the disease. The results indicate that the pinpoint hybridization method may be used for rapid diagnosis of influenza as a highly sensitive and specific tool.