1. Parasitic Diseases Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia;
2. Safe Water and AIDS Project, Kisumu, Kenya;
3. Task Force for Global Health, Atlanta, Georgia;
4. University of Basel, Basel, Switzerland;
5. Swiss Tropical and Public Health Institute, Basel, Switzerland;
6. Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya