Migration threatens to send flu south.
D000349:Africa / Q000453:epidemiology; D025041:Animal Migration; D000818:Animals; D000835:Animals, Wild / Q000502:physiology / Q000821:virology*; D001717:Birds / Q000502:physiology* / Q000821:virology*; D006801:Humans; D009980:Influenza A virus / Q000302:isolation & purification; D005585:Influenza in Birds / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission* / Q000821:virology; D008877:Middle East / Q000453:epidemiology; D011159:Population Surveillance; D015047:Zoonoses / Q000453:epidemiology / Q000635:transmission / Q000821:virology