This study is currently recruiting participants.
Trichuriasis is a parasitic infection. People get this infection when they ingest food or water that contains the eggs of a whipworm called Trichiuris trichiura. When the eggs hatch, the larvae infect the large intestine where they grow into adult worms. Infected people do not always have symptoms, but when they do, sSymptoms include abdominal pain, weight loss, diarrhea, and other illnesses. Healthy volunteers are needed to identify the minimal number of eggs needed to produce an infection without causing significant symptoms.
To infect healthy adults with whipworm eggs. Blood and stool will be collected for use in research.
Healthy adults aged 18 to 45 years in the Washington, DC, area.
Participants will visit the clinic 16 times over up to 8 months. They will be screened. They will have a physical exam with blood tests. They will give a stool sample.
Participants will ingest whipworm eggs in a small cup of water. For the next 10 clinic visits, they will provide blood and/or stool samples.
About 6 months after ingesting the eggs, participants will be treated with an anti-worm medication called albendazole. They will take the medication once in clinic and for 2 more days at home. They will provide stool samples over 3 more clinic visits to make sure the medication worked.
Some participants may go on to participate in a sub-study. They will not receive the antiworm medication after 6 months. They will provide stool samples up to 4 times a month. They will visit the clinic once a month for up to 5 years.
INCLUSION CRITERIA:
1. Males or females between 18 and 45 years, inclusive.
2. Good general health as determined by means of the screening procedures.
--Existing medical diagnoses or conditions (except those in the Subject Exclusion Criteria below) must be deemed as stable chronic medical conditions. A stable chronic medical condition is defined as no change in prescription medication, dose, or frequency of medication in the last 90 days and health outcomes of the specific disease are considered to be within acceptable limits in the last 180 days. Any change due to change of health care provider, or that is done for financial reasons, as long as in the same class of medication, will not be considered a violation of this inclusion criterion. Any change in prescription medication due to improvement of a disease outcome, as determined by the Principal Investigator or a co-investigator, will not be considered a violation of this inclusion criterion. Individuals may be taking chronic or as needed medications if, in the opinion of the Principal Investigator or co-investigator, they pose no additional risk to safety or assessment of reactogenicity and immunogenicity. Topical, nasal, and inhaled medications (with the exception of corticosteroids as outlined in the Subjects Exclusion Criteria), vitamins, and contraceptives are permitted.
3. Available for the duration of the trial (approximately 7.5 months).
4. Willingness to participate in the study as evidenced by signing the informed consent document.
5. Ability to sign and understand the informed consent document.
INCLUSION CRITERIA - T. trichiura Donor Sub-Study
1. Prior enrollment into the CHTI-01-21 clinical study.
2. Receipt of T. trichiura Egg inoculum.
3. Continues to meet all eligibility criteria for the CHTI-01-21 main clinical study.
4. Willingness to participate in the donor sub-study as evidenced by signing the sub-study informed consent document.
EXCLUSION CRITERIA:
1. Pregnancy as determined by a positive urine human choriogonadotropin (hCG) (if female).
2. Participant unwilling to use reliable contraception methods while participating in the study (if female of reproductive potential who is engaging in sexual activity that could lead to pregnancy); being of reproductive potential is defined as not being surgically sterile, abstinent from intercourse with a male partner, in a monogamous relationship with a vasectomized partner, at least 2 years post-menopausal, or determined otherwise by medical evaluation to be sterile.
3. Currently lactating and breast-feeding (if female).
4. History of clinically significant neurologic, cardiac, pulmonary, hepatic, rheumatologic, autoimmune, diabetes, or renal disease by history, physical examination, and/or laboratory studies.
5. Has a diagnosis of schizophrenia, bipolar disease or other major psychiatric condition that would make compliance with study visits/procedures difficult (e.g., subject with psychoses or history of suicide attempt or gesture in the 3 years before study entry, ongoing risk for suicide).
6. Known or suspected immunodeficiency or immunosuppression as a result of an underlying illness or treatment.
--Causes for immunosuppression may include, but are not limited to, poorly controlled diabetes mellitus, chronic liver disease, renal insufficiency, active neoplastic disease or a history of hematologic malignancy, connective tissue disease, organ transplant.
7. Laboratory evidence of liver disease (alanine aminotransferase [ALT] greater than 1.25-times the upper reference limit).
8. Laboratory evidence of renal disease (serum creatinine greater than 1.25-times the upper reference limit).
9. Laboratory evidence of hematologic disease (hemoglobin <11.1 g/dl [females] or <12.5 g/dl [males]; absolute leukocyte count <3.4 or >11.0 x 10^3/mm^3; absolute eosinophil count >0.6 x 10^3/mm^3 or platelet count <125 x 10^3/mm^3).
10. Positive fecal occult blood test.
11. Infection with a pathogenic intestinal helminth as determined by stool examination for ova and parasites.
12. History of iron deficiency anemia or laboratory evidence of iron deficiency (serum ferritin concentration below the lower reference limit).
13. Other condition that in the opinion of the investigator would jeopardize the safety or rights of a volunteer participating in the trial or would render the participant unable to comply with the protocol.
14. Volunteer has had medical, occupational, or family problems as a result of alcohol or illicit drug use during the past 24 months.
15. Positive ELISA for hepatitis B surface antigen (HBsAg).
16. Positive confirmatory test for HIV infection.
17. Positive confirmatory test for hepatitis C virus (HCV) infection.
18. Using or intends to continue using oral or parenteral corticosteroids, high-dose inhaled corticosteroids (>800 microg/day of beclomethasone dipropionate or equivalent) or other immunosuppressive or cytotoxic drugs within 30 days of the volunteer s expected enrollment in this study or planned use during the study.
19. Known allergy to benzimidazole class of compounds or any components of albendazole or mebendazole.
20. History of previous infection with T. trichiura or continuous residence for more than 6 months in a T. trichiura-endemic area.
21. Inability to speak English.
22. Current/planned simultaneous participation in another study of an investigational agent or device for the duration of their study participation.
EXCLUSION CRITERIA - T. trichiura Donor Sub-Study
1. Pregnancy as determined by a positive urine human choriogonadotropin (hCG) (if female).
2. Receipt of albendazole after enrollment into CHTI-01-21 study and prior to the T. trichiura Donor Sub-Study (Day 182).
3. Hemoglobin <11.1 g/dl [females] or <12.5 g/dl [males] on the most recent complete blood count done as part of the primary study.
4. Positive serological test for HBsAg, positive confirmatory test for HIV infection or positive confirmatory test for HCV infection during CHTI-01-21 main study and prior to the T. trichiura Donor Sub-Study (Day 182).
5. Withdrawal from CHTI-01-21 prior to the T. trichiura Donor Sub-Study (Day 182).
6. Experience of any Serious Adverse Event or Adverse Event of Special Interest during the main study, prior to the T. trichiura Donor Sub-Study (Day 182).