Standard vs High-Dose Trivalent Inactivated Flu Vaccine in Adult Hematopoetic Stem Cell Transplant (HSCT) Recipients

Inclusion Criteria: * Allogeneic hematopoietic stem cell transplant recipients who are \>6 post-transplant * greater than or equal to 18 years of age * Available for duration of study * If patients are on immunosuppressive therapy for treatment of graft versus host disease (GVHD): only those on stable doses for at least 4 weeks or on tapering doses will be eligible. Exclusion Criteria: * History of hypersensitivity to previous influenza vaccination or hypersensitivity to eggs/egg protein * History of Guillain-Barre syndrome * Evidence of hematologic malignancy or disease relapse post-transplant (mixed chimerisms and molecular evidence of disease is permitted) * Non-allogeneic (e.g. autologous) hematopoietic SCT recipients * History of receiving 2011 - 2012 influenza vaccine * History of proven influenza disease after September 1, 2011. * Pregnant females * Have any condition that would, in the opinion of the site investigator, place them at an unacceptable risk of injury or render them unable to meet the requirements of the protocol * Have any condition that the investigator believes may interfere with successful completion of the study * Platelet count less than 50,000 cells/μL * History of known infection with HIV, Hepatitis B or Hepatitis C * History of known latex hypersensitivity