I got a flu shot, so why did I still get the flu?
D006801:Humans; D009980:Influenza A virus / Q000276:immunology; D009981:Influenza B virus / Q000276:immunology; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000517:prevention & control* / Q000821:virology
D007252:Influenza Vaccines