WHO influenza surveillance.
D004196:Disease Outbreaks / Q000266:history / Q000517:prevention & control*; D049673:History, 20th Century; D006801:Humans; D007252:Influenza Vaccines; D007251:Influenza, Human / Q000266:history / Q000517:prevention & control* / Q000821:virology; D007253:Information Centers / Q000458:organization & administration; D011159:Population Surveillance; D014944:World Health Organization / Q000266:history / Q000458:organization & administration
D007252:Influenza Vaccines