title: Flu vaccination challenge enters third season with room for more participants and better rates.
mesh_terms: D006801:Humans; D017589:Immunization Programs / Q000458:organization & administration*; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000453:epidemiology / Q000517:prevention & control*; D007591:Joint Commission on Accreditation of Healthcare Organizations; D014481:United States / Q000453:epidemiology
chemical_list: D007252:Influenza Vaccines