Evaluation of Influenza-Specific Immune Responses in Children and Adults During the 2010-2011 Influenza Season in the U.S.

Inclusion Criteria: * Children ages 6 through 17 years and adults 18 years of age or older * Able to provide proof of identity to the satisfaction of the study clinician completing the enrollment process * Able and willing to complete the informed consent/assent process * Willing to donate blood for storage and for research, at least at three study visits * Willing to have genetic tests performed on stored blood for research purposes Exclusion Criteria: * Known to be pregnant. * Medical, psychiatric, occupational or other condition that, in the judgment of the site investigator, is a contraindication to protocol participation or impairs a subject's ability to give informed consent. * Bleeding disorder diagnosis or any contraindications to blood drawing as assessed by the site investigator * Immune system known to be compromised by HIV or other active infection, active cancer, or systemic immunosuppressive treatments. * Seasonal influenza vaccine within the 12 weeks prior to enrollment. * Another subject from the same household enrolled into the same age group.