Effect of Filarial Infection on Immune Responses in Latent Tuberculosis

Study Summary

Background: \- Lymphatic filariasis is an infection that is caused by small, thread-like worms. It is spread by mosquitoes, and causes fever, chills, and headaches. If untreated, it can also cause elephantiasis, a condition that leads to swelling of the arms, legs, breasts, and scrotum. Treatment can eliminate the worms from the blood and reduce the risk of developing elephantiasis. Researchers want to study people with latent tuberculosis (TB) who may or may not be infected with filariasis. This study will look at the way that people with latent TB fight infection with these worms. Objectives: \- To study how the immune systems of people with latent TB react to filarial infection. Eligibility: \- Individuals between 18 and 65 years of age who have latent TB and may or may not have filarial infection. Design: * Participants will be screened with a physical exam and medical history. They will provide a blood and stool sample to test for infection. * Participants who do not have lymphatic filariasis but have another kind of intestinal worm will be treated for the parasite. This will be their last study visit. * Participants who have latent TB and lymphatic filariasis will be treated with the standard treatment for the disease. They will come back for a second visit 6 months later, and will provide another blood sample.