Inclusion Criteria:
* Participation in ancillary clinical research study
* Able to give informed consent
* Age 18-50 years old for Arm 1 and Arm 2
* Age 65-80 years old for Arm 3, Arm 4, and Arm 5
* Weight of at least 110 lbs as determined by self-reporting
Exclusion Criteria:
* Inability to give informed consent
* Refusal or inability to have blood drawn or participate in study procedures
* Previous adverse reaction to influenza vaccine or medical history contraindicated for receiving influenza vaccine, including but not limited to:
1. History of Guillain-Barre Syndrome
2. History of egg allergy
3. History of gelatin allergy
4. History of moderate to severe illness with or without fever within 6 weeks of receipt of influenza vaccine
* Previous receipt of influenza vaccine outside of study within current season
* Bleeding disorder diagnosed by a doctor (eg, factor deficiency, coagulopathy, or platelet disorder requiring special precautions)
* Participant has any medical, psychiatric, or social condition, or occupational or other responsibility that, in the judgement of the investigator would interfere with, or serve as a contraindication to the planned procedure(s).
* These following criteria are used for scientific reasons, and not safety reasons. Specifically, the criteria are used to obtain a population that is healthy and less likely to have conditions that may influence the immune system:
1. No recent respiratory infections in the past 4 weeks at time of vaccination
2. Malignancy
3. Evidence of Inflammation: Systemic Lupus Erythematosis, Rheumatoid Arthritis, Polymyositis, Dermatomyositis, Scleroderma, Crohn's Disease, Ulcerative Colitis.
4. Lymphoproliferative Disorder
5. Known Immunodeficiency
6. Myocardial Infarction \<6 months
7. Cerebral Vascular Accident
8. Peripheral Vascular Disease- recannulation \<6months
9. Cardiac Insufficiency - congestive heart failure
10. Hypertension with increased blood urea nitrogen (BUN)
11. Renal Failure
12. Dementia
13. Alcoholism (defined as \>17 drinks/week)
14. Drug Abuse (excluding marijuana)
15. HIV positive
16. History of hepatitis
17. History of immunization within 4 weeks of study participation or plan to receive non- IIV vaccination within 4 weeks of receiving IIV
18. Moderate to severe illness at time of enrollment
* Donations of blood in the 8 weeks prior to enrollment which, combined with expected volumes to be drawn for this study, would exceed 450 mL in an 8 week period.
* Current pregnancy at time of enrollment or pregnancy within last 4 months
* Active or planned breastfeeding during study participation
* Psychiatric condition that precludes compliance with the protocol. Specifically excluded are persons with psychoses within the past 3 years, ongoing risk for suicide, or history of suicide attempt or gesture within the past 3 years.
