Characterization of Human Memory Immune Responses to Prior Yellow Fever Vaccination

Launched by EMORY UNIVERSITY · Nov 18, 2010

Keywords

ClinConnect Summary

This is an observational study that aims to understand how the immune system remembers the yellow fever vaccine. Researchers will look at two parts of the immune system— antibodies and memory T cells—by analyzing blood samples from people who have already been vaccinated. The goal is to see how strong and how long this memory lasts, and to compare younger adults (18–45 years) with older adults (55+). Participants will not receive any new vaccines as part of the study; it involves collecting blood to study past vaccination.

Who can join and what to expect: healthy adults who have documentation showing they received the yellow fever vaccine are eligible, with two age groups: 18–45 and 55 or older. Key exclusions include having received any vaccine within 30 days of the study visit (older adults are an exception), significant immune system problems, HIV, hepatitis B or C, recent blood products, pregnancy, or use of immune-suppressing medications. The study, which plans to enroll about 300 people, will involve one or more blood draws at The Hope clinic of Emory Vaccine Center in Decatur, Georgia. It is led by Emory University with collaboration from NIAID and is currently enrolling by invitation.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Able to understand and give informed consent
• • Age 18-45 years (Group 1) or 55 years and above (Group 2) at the time of yellow fever vaccination
• • Documentation (international certificate of vaccination (yellow card) or medical record) indicating receipt of yellow fever vaccine.
• Exclusion Criteria:
• • Recipient of any vaccines within 30 days before the study visit (not applicable to older adults)
• • History of a progressive and severe chronic medical condition resulting in impaired immunity (such as diabetes, kidney or liver dysfunction)
• • Required use of immunosuppressive medications
• • Reporting HIV, Hepatitis B (surface antigen positive) or Hepatitis C infections (antibody positive) on the medical/health history form
• • Recipient of a blood product or immune globulin product within 42 days of study visit
• • Reporting pregnancy