Flu Infection at UPHS

Inclusion Criteria: 1. Provision of signed and dated informed consent form 2. Stated willingness to comply with all study procedures and availability for the duration of the study 3. Aged 18 years and older 4. Influenza positive test result performed within the University of Pennsylvania Health System Exclusion Criteria: 1. Known latex allergy 2. Immunosuppression as a result of an underlying illness or treatment with immunosuppressive or cytotoxic drugs, or use of anticancer chemotherapy or radiation therapy within the preceding 36 months 3. Pregnancy due to the volume of blood collected in this study 4. Treatment with immunoglobulin or another blood product within the 3 months prior to enrollment in this study 5. Any neoplastic disease (excluding non-melanoma skin cancer or prostate cancer that is stable in the absence of therapy) or a history of any hematological malignancy ("active" is defined as having received treatment within the past 5 years) 6. Known acute or chronic medical condition that, in the opinion of the investigator or appropriate sub-investigator, would interfere with the evaluation of immune responses 7. Intends to donate blood during the study period 8. A known human immunodeficiency virus, hepatitis B, or hepatitis C infection 9. Any condition that would, in the opinion of the site investigator, place the subject at an unacceptable risk of injury or render the subject unable to meet the requirements of the protocol 10. Prolonged inpatient hospitalization that disrupts or interferes with study procedures. 11. Weigh less than 110lbs