With its predilection for striking young and healthy adults more than children and the elderly, the 1918 “Spanish” influenza virus is believed to have differed from contemporary strains in its mechanism of action. New research is now illuminating this mechanism, pointing to viral effects that activated the innate immune response to levels that were so damaging to the lungs that acute respiratory distress, severe tissue damage, edema and hemorrhage, and pneumonia resulted in many individuals (Kobasa D et al. Nature. 2007;45:319-323).
Hampton T. Virulence of 1918 Influenza Virus Linked to Inflammatory Innate Immune Response. JAMA. 2007;297(6):580. doi:10.1001/jama.297.6.580