Effect of Concomitant Mansonella Perstans Microfilaremia on Immune Responses Following Single Dose Praziquantel in People With Schistosomiasis

Background: Schistosomiasis is a chronic infection. It is caused by parasitic worms called Schistosoma haematobium (Sh) that are spread by snails that live in rivers. It can lead to liver problems or bladder cancer. Praziquantel (PZQ) is a drug used to treat this infection. After taking it, some people develop increased resistance to reinfection with Sh. Some people with Sh infection can be infected with another worm called Mansonella perstans (Mp). Mp is spread through a biting insect called a midge. It rarely causes symptoms. However, researchers think that Mp infection could affect the body s response to PZQ treatment for or risk of reinfection with Sh. Objective: To find out the effects of Mp infection on the response to PZQ treatment for Sh infection. Eligibility: Men and women ages 14-80 who: * Live in Tieneguebougou, Bougoudiana, or surrounding villages in Mali * Are not pregnant * Have Sh infection * Have no other chronic medical conditions Design: * Participants will be screened with: * Medical history * Physical exam * Blood and urine tests * Stool samples * Participants will be treated with a single dose of PZQ by mouth. * After receiving PZQ, participants will return to the clinic for blood and urine tests at the following times: * 4, 8, 24, 48, and 72 hours later * 5, 7, 9, and 14 days later * 1, 3, and 6 months later Participants who are infected with Sh at the 6-month visit will get another treatment with PZQ. ...