Understanding how long vaccines protect against infections

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This study investigates the durability of immune responses generated by two different vaccines: the yellow fever vaccine and the quadrivalent influenza vaccine. Participants aged 18-50 will receive one of these vaccines, and researchers will collect biological samples from their blood, lymph nodes, and bone marrow to analyze how the immune system responds over time. The goal is to identify the signals that contribute to long-lasting immunity, which is currently difficult to predict during vaccine development. This research aims to enhance our understanding of vaccine-induced protection and improve future vaccine design.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Able to understand and give informed consent.
* Age 18-50 years.
* Participants agree not to take any live vaccines 30 days before or after (14 days for inactivated) vaccination.
* Women of child bearing potential must agree to use effective birth control for the first 3 months of the study. A negative urine pregnancy test must be documented prior to vaccination and prior to tissue sampling procedures.

Exclusion Criteria:

* History of allergy or serious adverse reaction, including Guillain-Barré syndrome, to a vaccine or vaccine products.
* History of a medical condition resulting in impaired immunity (such as HIV infection, cancer, particularly leukemia, lymphoma, use of immunosuppressive or antineoplastic drugs or X-ray treatment). Persons with previous skin cancers or cured non-lymphatic tumors are not excluded from the study.
* History of Hepatitis B or Hepatitis C infection.
* Chronic clinically significant medical problems that could affect the immune response, require medication that would affect the immune response, or have signs or symptoms that could be confused with reactions to vaccination, including (but not limited to):

  1. Insulin dependent diabetes
  2. Severe heart disease (including arrhythmias)
  3. Severe lung disease
  4. Severe liver disease
  5. Severe kidney disease
  6. Grade 4 hypertension (\*Grade 4 hypertension per CTCAE criteria is defined as life-threatening consequences (e.g., malignant hypertension, transient or permanent neurologic deficit))
* Thymus gland problems (such as myasthenia gravis, DiGeorge syndrome, thymoma) or removal of thymus gland or history of uncontrolled autoimmune disorder.
* Pregnancy or breast feeding, or plans to become pregnant in the first 3 months of study participation.
* Receipt of blood products or immune globulin product within the prior 3 months.
* Active duty military.
* History of excessive alcohol consumption, drug use, psychiatric conditions, social conditions or occupational conditions that in the opinion of the investigator would preclude compliance with the trial.

Additional Exclusion Criteria for YF-17D Arm

* History of previous yellow fever, West Nile, Dengue, St. Louis encephalitis, or Japanese encephalitis vaccination or infection.
* Previous residence in a country where there is a risk of yellow fever virus (YFV) transmission
* History of allergy to eggs, chicken, or gelatin.

Additional Exclusion Criteria for QIV Arm

* History of influenza infection within the same influenza season.

Where it's running

• Emory University Hospital
  Atlanta, Georgia, United States Recruiting
• Emory Winship Cancer Institute
  Atlanta, Georgia, United States Recruiting
• The Hope Clinic of Emory University
  Decatur, Georgia, United States Recruiting

Study contacts

• Principal investigator: Nadine Rouphael, MD — Emory University
• Study coordinator: Nadine Rouphael, MD
• Email: nroupha@emory.edu
• Phone: 404-712-1435

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.