Inclusion Criteria:
In order to be eligible to participate in this study, an individual in the COPD group must meet all of the following criteria:
* Age\>40 years old
* Physician diagnosis of COPD confirmed by post-bronchodilator testing (defined as forced expiratory volume in one second (FEV1)/forced vital capacity (FVC)\< lower limit of normal and FEV1/FVC\<0.70) and FEV1\>30% predicted based on spirometry testing available in the prior year or completed at screening (if no historical testing available)
* Free of acute exacerbation of COPD for prior four weeks at time of recruitment
* Resting oxygen saturation \>94 percent
* Blood pressure systolic values between 90-160 mm Hg and diastolic between 55-90 mm Hg
* No nasal symptoms based on questionnaire
* Willingness and ability to participate in study procedures
* Completion of informed consent
In order to be eligible to participate in this study, an individual in the healthy control group must meet all of the following criteria:
* Age\>40 years old
* Spirometry testing showing normal lung function (defined as pre and post--bronchodilator FEV1/FVC\>=lower limit of normal and FEV1\>80 percent predicted) based on spirometry testing available in the prior year or completed at screening (if no historical testing available)
* Resting oxygen saturation \>94 percent
* Blood pressure systolic values between 90-160 mm Hg and diastolic between 55-90 mm Hg
* No nasal symptoms based on questionnaire
* Willingness and ability to participate in study procedures
* Completion of informed consent
Exclusion Criteria:
* Inability or unwillingness to consent
* Active tobacco or e-cigarette use (within last six months)
* Active diagnosis of asthma
* Any regular suppressive antibiotics (i.e., azithromycin)
* Daily oral prednisone use
* Any supplemental oxygen use beyond nocturnal oxygen therapy
* Use of intranasal corticosteroids in the 30 days prior to screening visit
* Chronic illness associated with immunosuppression (i.e., HIV, malignancy)
* History of documented or self-reported positive Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection requiring hospitalization
* Receipt of SARS-CoV-2 vaccine within 14 days prior to study screening visit or plan to receive SARS-CoV-2 vaccine from screening visit to 14 days after completion of all study procedures
* History of epistaxis, prior nasal surgery or anatomical abnormalities
* Current use of blood thinner beyond full dose aspirin \[e.g., warfarin (coumadin), clopidogrel (Plavix), dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis)\]
* Self-reported history of easy bruising or bleeding gums
* Serological evidence of HIV infection at screening (Positive HIV antibody test)
* Relative leukopenia (WBC\<4000), neutropenia (Absolute neutrophil count\<2000) or lymphopenia (absolute lymphocyte count\<1500) on screening CBC
* Respiratory infection (cough, sore throat, sinusitis, fever) within prior 4 weeks
* Active wheezing at day 0 visit
* Pregnancy or nursing or women who are currently trying to become pregnant. (All female subjects, except those who have had a hysterectomy with oophorectomy, will undergo urine pregnancy testing on the morning of the screening visit and again on the on Day 0 at the time of arrival to the lab and prior to LAIV administration. A positive pregnancy test will exclude the subject)
* Use of chronic immunosuppression in the 30 days prior to screening visit
* History of hypersensitivity, especially anaphylactic reactions, to egg proteins, gentamicin, gelatin, or arginine, or with a reaction to previous influenza vaccination at a severity level precluding the subject's participation as judged by the study physician
* History of Guillain-Barre syndrome
* Subjects who will be unable to avoid contact with immunocompromised individuals for 3 weeks after receiving LAIV vaccine
* Receipt of the LAIV during the current or prior flu vaccine season
* Physician diagnosed influenza, a positive test for influenza or suspicion of influenza illness in the 18 months prior to enrollment. Suspicion of influenza will be based on the CDC's influenza-like illness case definition ("fever\>100 °F AND cough/sore throat in the absence of a known cause other than influenza. Temperature can be measured in the office or at the home")
* Any condition that, in the opinion of the study investigator, would compromise the subject's ability to participate in the study
