title: Viruses from ducks and chickens dominate the family tree of H7N9.
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000821:virology; D002645:Chickens / Q000821:virology*; D002681:China / Q000453:epidemiology; D004372:Ducks / Q000821:virology*; D009980:Influenza A virus / Q000502:physiology*; D005585:Influenza in Birds / Q000453:epidemiology / Q000821:virology*; D007564:Japan / Q000453:epidemiology; D056910:Republic of Korea / Q000453:epidemiology