Influenza A is an RNA virus classified by its surface hemagglutinin and neuraminidase protein subtypes, which infects respiratory epithelial cells, causing cell death and enabling person-to-person transmission via respiratory secretions. Its clinical significance in respiratory medicine stems from its capacity to cause recurring winter epidemics and occasional pandemics, its ability to exacerbate underlying chronic cardiopulmonary and renal disease, and its predisposition toward severe complications including secondary bacterial pneumonia and primary viral pneumonia. Diagnosis relies on detection of viral antigen or nucleic acid, and management centers on antiviral neuraminidase inhibition, prevention of transmission, and vaccination.
Influenza A is an RNA virus classified by its surface hemagglutinin and neuraminidase protein subtypes, which infects respiratory epithelial cells, causing cell death and enabling person-to-person tr…