When the flu killed millions.
Armstrong
J F
JF
PENNSTAR Flight Program, University of Pennsylvania Medical Center, Philadelphia, USA.
D003140:Communicable Disease Control / Q000266:history; D004196:Disease Outbreaks / Q000266:history*; D005060:Europe / Q000453:epidemiology; D014943:Global Health; D049673:History, 20th Century; D006801:Humans; D007251:Influenza, Human / Q000453:epidemiology / Q000266:history*; D008889:Military Personnel / Q000266:history; D014481:United States / Q000453:epidemiology