This is a specimen collection protocol designed with the purpose of understanding the immune responses to influenza in children and adult subjects through collection of blood specimens and influenza medical history data. This protocol will allow the investigators to evaluate influenza-specific immune responses to a variety of influenza strains in a broad age range of the U.S. population early and late in the 2010-2011 influenza season. Immune responses will be evaluated using blood samples. The underlying hypothesis for this protocol is that the detailed characterization of immune responses to influenza in subjects from different age groups will further the understanding of immune responses cross-reactivity and advance development of influenza vaccines that are cross-reactive against old, new and re-emerging influenza strains.

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.

Healthy participants ages 6 years and older who are available for 3 clinic study visits over approximately eight months. Participants must be willing and able to donate blood for storage and research. Females must not be or become pregnant during the study. Multiple subjects from the same household may not be enrolled into the same age group.