Between a virus and a hard place.
D002487:Centers for Disease Control and Prevention, U.S.; D004196:Disease Outbreaks; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000502:physiology*; D007251:Influenza, Human / Q000453:epidemiology*; D014481:United States; D014944:World Health Organization