Safety and Immunogenicity of BPL-1357, A BPL-Inactivated, Whole-Virus, Universal Influenza Vaccine

* INCLUSION CRITERIA: Individuals must meet all of the following criteria to be eligible for study participation: * 18 and \<= 55 years of age. * Non-smoker (tobacco and cannabis) and does not use vape or e-cigarette products. * Has not received influenza vaccination of any type in the 8 weeks prior to enrollment and willing to not receive influenza vaccination of any type until after the V2D56 visit. Participants who enroll in our study will be informed of the Centers for Disease Control and Prevention (CDC) recommendation to receive seasonal influenza vaccination annually. * Has not received Coronavirus Disease 19 (COVID-19) vaccination of any type in the 4 weeks prior to enrollment and willing to not receive COVID-19 vaccination of any type until after the V2D28 visit. Participants who enroll in our study who are interested in getting a COVID-19 vaccination will be counselled to receive it prior to enrolling into our study. * A female participant is eligible for this study if she is not pregnant or breastfeeding and meets one of the following criteria, beginning at least 4 weeks prior to enrollment through the end of the study period (V2D182): * Is infertile, including postmenopausal status (as defined by no menses for \>= 1 year) or history of hysterectomy or bilateral oophorectomy. * Agrees to practice abstinence. * Agrees that, with heterosexual intercourse with a fertile male partner, she will use an acceptable form of contraception and her male partner will use a condom with spermicide. Acceptable effective methods of female contraception include the following: bilateral tubal ligation, implant of levonorgestrel, injectable progestogen, intrauterine device, oral contraceptive pills, and diaphragm with spermicide. * Able to provide informed consent. * Able to speak English. * Human immunodeficiency virus (HIV) uninfected with a negative test within 60 days of enrollment. * Does not use IN medications (including but not limited to nasal sprays, sinus rinses), over-the-counter medications (including but not limited to aspirin, decongestants, antihistamines, and other nonsteroidal anti-inflammatory drugs), and herbal medications (including but not limited to herbal tea or St. John s Wort) within 14 days prior to study enrollment, and agrees not to use these mediations through the final study visit, unless approved by the investigator. * Agrees not to donate blood or blood products from 3 months prior to enrollment through the final study visit. EXCLUSION CRITERIA: Individuals meeting any of the following criteria will be excluded from study participation: * Presence of self-reported or medically documented significant medical condition including but not limited to: * Chronic pulmonary disease (e.g., asthma, emphysema). * Chronic cardiovascular disease (e.g., cardiomyopathy, congestive heart failure, cardiac surgery, ischemic heart disease, known anatomic defects). * Chronic medical conditions requiring close medical follow-up or hospitalization during the past 5 years (e.g., insulin-dependent diabetes mellitus, renal dysfunction, hemoglobinopathies). * Immunosuppression, immune deficiency, or ongoing malignancy. * Neurological and neurodevelopmental conditions (e.g., Bell s palsy, cerebral palsy, epilepsy, stroke, seizures). * Postinfectious or postvaccine neurological sequelae including GBS. * Body mass index (BMI) \<= 18 and \>= 35. * Acute illness within 7 days prior to enrollment. * Individuals who have grade 2 or above clinically significant laboratory values outside the limits thus specified by normal laboratory parameters. * Known allergy to influenza vaccination or excipients contained in the influenza vaccine used. * Known allergy to lidocaine or phenylephrine. * Receipt of blood or blood products (including immunoglobulins) within 3 months prior to enrollment. * Receipt of any unlicensed drug within 3 months or 5.5 half-lives (whichever is greater) prior to enrollment. * Receipt of any unlicensed vaccine within 6 months prior to enrollment, not including COVID-19 vaccines under Emergency Use Authorization. * Self-reported or known history of alcoholism or drug abuse within 6 months prior to enrollment, or positive urine test for drugs of abuse (i.e., amphetamines, cocaine metabolites, benzodiazepines, opiates, or tetrahydrocannabinol) prior to vaccination on V1D0. * Self-reported or known history of psychiatric or psychological issues that require treatment and are deemed by the principal investigator (PI) to be a contraindication to protocol participation. * History of angioedema or anaphylaxis. * History of SARS-COV-2 infection with residual or ongoing symptoms. * Any condition or event that, in the judgment of the PI, is a contraindication to protocol participation or impairs the participant s ability to give informed consent.