1. Division of Parasitic Diseases, Centers for Disease Control and Prevention,1 and
2. Unidad de Parasitologı́a, Universidad San Pablo CEU, Madrid, Spain2; and
3. Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro (UERJ), and Hospital Evandro Chagas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil3
4. Department of Physiology, Morehouse School of Medicine,4 Atlanta, Georgia;