The influenza pandemic of 1918-1919 killed approximately 50 million people. The 
unusually severe morbidity and mortality associated with the pandemic spurred 
physicians and scientists to isolate the etiologic agent, but the virus was not 
isolated in 1918. In 1996, it became possible to recover and sequence highly 
degraded fragments of influenza viral RNA retained in preserved tissues from 
several 1918 victims. These viral RNA sequences eventually permitted 
reconstruction of the complete 1918 virus, which has yielded, almost a century 
after the deaths of its victims, novel insights into influenza virus biology and 
pathogenesis and has provided important information about how to prevent and 
control future pandemics.