CVD 37000: Immunity and Microbiome Studies at Intestinal and Systemic Sites in Ty21a Vaccinated Adults
Typhoid Vaccination
About this trial
This is an interventional basic science trial for Typhoid Vaccination
Eligibility Criteria
Inclusion Criteria:
- Age 18 years and older
- Undergoing colonoscopy for screening or surveillance for colorectal cancer at the University of Maryland
- Provide written informed consent prior to initiation of any study procedures
- Healthy, as defined by considered fit to undergo outpatient elective colonoscopy by the referring health care provider
Exclusion Criteria:
- Pregnancy or nursing mother
- Known coagulopathy or bleeding disorder preventing mucosal biopsy
- History of Crohn's disease or ulcerative colitis
- Surgical removal of the ileocecal valve or any part of the small or large intestine
- Allergic reaction to oral typhoid vaccine in the past
Immunosuppression from illness or treatment, including
- immune-deficiency disorders such as Human Immunodeficiency Virus (HIV) or Acquired Immunodeficiency Syndrome (AIDS)
- leukemia, lymphoma, or cancers
- immune suppressive medications or treatments, such as corticosteroids or radiation
- Receipt of any other vaccine two weeks prior to receipt of Ty21a
- Positive urine pregnancy test (HCG) prior to colonoscopy or vaccination
Sites / Locations
- Universtiy of Maryland, Baltimore, Center for Vaccine Development and Global Health
Arms of the Study
Arm 1
Arm 2
Arm 3
Experimental
Experimental
No Intervention
Vaccination, Colonoscopy
Colonoscopy, Vacciniation, Colonoscopy
Colonoscopy Without Vaccination
Individuals receive immunization with Vivotif typhoid vaccine prior to routine colonoscopy examination. During colonoscopy, small bowel biopsies will be obtained to examine immune responses and microbiota at the mucosal level; brushings will also be obtained.
Individuals receive immunization with Vivotif typhoid vaccine after initial colonoscopy exam and specimen collection and prior to a routine follow up colonoscopy examination during which additional specimens will be collected.
Individuals do not receive immunization but consent to collection of specimens during colonoscopy. The specimens to be collected in all three groups include stool, saliva, and small bowel biopsies (terminal ileum).