Why do flu shots weaken with age? new study aims to find out

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Able to speak and read English * Male or Female, 65 years and older by date of enrollment * Weight of 110 lbs or greater * Has received influenza vaccine in the past seasons without severe adverse reactions * Willing to receive an FDA-approved age-appropriate and CDC-recommended influenza vaccine for each of the 2022-23, 2023-24, and 2024-25 influenza seasons * Willing to withhold all other vaccinations 2 weeks prior and 2 weeks after flu vaccination for the 2022-23, 2023-24, and 2024-25 influenza seasons * Willing and available to participate in 19 study visits over three years around influenza vaccination * Willing to provide blood samples at sixteen visits over three years * Willing to agree to genomic testing of samples and sharing of de-identified genomic data generated from samples at the conclusion of the research Exclusion Criteria: * Received any vaccine (shingles, pneumococcal, COVID, etc.) within 2 weeks of anticipated flu vaccination for the 2022-23, 2023-24, and 2024-25 influenza seasons. * Has already received an influenza vaccine for the approaching influenza season (2022-23) * Has known allergy to eggs or any component of the flu vaccine. \[Although the Advisory Committee on Immunization Practices (ACIP) has concluded that a history of anaphylactic/anaphylactoid or severe allergic reaction to eggs should no longer be considered a contraindication to vaccination with any age-appropriate vaccine, for the purposes of this research study we elected to exclude individuals with these allergies\] * History of Guillain-Barre syndrome (GBS) * Body temperature greater than 100.3°F (38°C) on date of vaccination or within 2 days prior to vaccination by participant report (study entry may be delayed to meet this requirement) * Rockwood Frailty Index score of \>0.21 * Known history of any of the following co-morbid conditions: * Chronic or recent (within past 2 months) infection requiring oral or intravenous antibiotics, antifungals, or antivirals * Cancer other than basal cell carcinoma requiring active surgical or medical treatment (chemotherapy or radiation therapy) * Congestive Heart Failure * Ischemic Heart Disease * Congenital abnormalities (PI to evaluate) * Paget's disease * Renal failure requiring ongoing dialysis * Chronic obstructive pulmonary disease, emphysema, or asthma * Severe autoimmune disease requiring biological therapy * Diabetes mellitus requiring insulin * Use of medicines during past 6 months known to alter immune response such as high-dose corticosteroids (≥ 10 mg/day of prednisone or equivalent) * HIV, AIDS or other immunodeficiency disorders * Recent (≤ 3 months) severe trauma or major surgery (PI to evaluate) * Current substance and/or alcohol abuse * Patients currently residing in the Department of Correction * Inability to comply with the protocol requirements * Any other condition that, in the opinion of the PI, might interfere with study objectives