An observational study in Filariasis, Helminthiasis and Parasitic Infection, sponsored by National Institute of Allergy and Infectious Diseases (NIAID). Active, not recruiting at 1 site in United States. Open to participants aged 3 Years to 100 Years. Per ClinicalTrials.gov, last updated 2026-10-30.
Sponsored by National Institute of Allergy and Infectious Diseases (NIAID) · Observational
This study will evaluate and treat patients with filarial infections to explore in depth the immunology of the disease, including susceptibility to infection, disease development, and response to treatment. Filarial infections are caused by parasitic worms. The immature worm (larva) is transmitted to a person through a mosquito bite and grows in the human body to 2 to 4 inches in length. Although many of these infections do not produce symptoms, especially in the early stages of infection, others can have serious consequences, including swelling of the limbs or genitalia, allergic-lung problems, skin rash, eye inflammation that can lead to blindness, and heart disease. This protocol does not involve any experimental diagnostic procedures or treatments, and will use only procedures employed in the standard practice of medicine.
Persons between 3 and 100 years of age diagnosed with or suspected of infection with Wuchereria bancrofti, Bugia malayi, Onchocerca volvulus, Loa loa, or other parasitic worms may be eligible for this study.
Participants will have routine tests to determine the specific type of filarial infection. These may include special tests of the lungs, skin or heart, depending on the type of parasite suspected. Patients with skin reactions may have a "punch biopsy" to examine a small piece of affected skin. For this procedure, an area of skin is numbed with an anesthetic and a small circular area, about 1/3-inch in diameter and 1/2-inch thick, is removed using a sharp cookie cutter-type instrument. Some patients may require bronchoalveolar lavage. For this procedure, the mouth and throat are numbed with lidocaine jelly and spray and, if needed, a sedative is given for comfort. A small plastic tube is placed in a vein to give medications. A pencil-thin tube is then passed through the nose or mouth into the lung airways to examine the airways. Salt water is injected through the bronchoscope into the air passage, acting as a rinse. A sample of the fluid is then withdrawn and examined for infection, inflammatory cells and inflammatory chemicals. (Bronchoalveolar lavage is done only if medically necessary and only on patients 21 years or older.) Once the diagnosis is established, standard treatment will be instituted with either diethylcarbamazine or ivermectin, depending on the type of infection.
Additional procedures for research purposes include:
Patients admitted on this protocol will have, or be suspected of having, one of the filarial infections affecting humans. After routine clinical evaluation they will be studied in depth immunologically, and their blood cells and/or serum will be collected to provide reagents (eg., specific antibodies, T-cell clones, etc.) that will be used in the laboratory to address the broader questions of diagnosis, immunoregulation, pathology and immunoprophylaxis. Careful observations of the patients' clinical and immunologic responses to therapy will be made, as well as long-term follow-up of these changes. It is anticipated both that the patients will receive optimal clinical care for their infections and that the specimens collected from them will prove to be valuable reagents for the laboratory studies of the immunologic responses unique to filarial or other related helminth infections.
35 studies on the registry are indexed under Onchocerciasis; 7 are open to participants now.
Browse Onchocerciasis studies →National Institute of Allergy and Infectious Diseases (NIAID) is the lead sponsor of 2,446 studies on the registry; 179 are open to participants now.
Of its 405 completed or terminated interventional studies of FDA-regulated products, 302 (75%) have results posted.
Compared within Onchocerciasis, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Filariasis. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Males and females having or suspected of having a filarial infections will be enrolled. The participants will either have been native residents of endemic regions where these filarial infections are prevalent or they would have acquired the infection while traveling to such regions.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Age 3-100 years.
Access to a primary medical care provider outside of the NIH.
Ability to give .
Clinical evidence suggestive of a filarial infection
EXCLUSION CRITERIA:
Although pregnant or nursing women can be enrolled, they will be excluded from receiving treatment while pregnant or breastfeeding
Less than 3 year of age; greater than 100 years of age
Any condition that the investigator feels put the subject at unacceptable risk for participation in the study
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Patients that have, or are suspected of having, one of the filarial infections affecting humans
Drug: Diethylcarbamazine
Diethylcarbamazine is a drug administered under an IND held by the CDC. Standard dosing is used.
Define the determinants of the susceptibility to filarial infection, the development of filarial disease and the beneficial or adverse response to chemotherapy
Susceptibilities to filarial infection will be determined
Time frame: 10 years
To identify clinical and biological markers of successful treatment in filarial-infected individuals
Identification of clinical and biological markers of successful treatments
Time frame: 10 years
To characterize the immunoregulatory mechanisms at play in filaria-infected individuals
Characterization of immunoregulatory mechanisms
Time frame: 10 years
To create a serum and cell bank for the study of filarial infections of humans both before and at fixed times following definitive treatment.
Cell and serum bank will be maintained.
Time frame: 10 years
To understand the natural history of filarial infections in expatriates and other travelers and in immigrant populations
Better understanding of natural history of infections in expatriates and travels
Time frame: 10 years
Plan to share: Undecided
Started Mar 1991 (actual).
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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National Institute of Allergy and Infectious Diseases (NIAID) →