1. Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, Georgia.
2. Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia.
3. Instituto de Biología Molecular y Biotecnología, Universidad Mayor de San Andrés, La Paz, Bolivia.
4. Emory School of Medicine, Atlanta, Georgia.
5. Servicio Departamental de Salud, La Paz, Bolivia.
6. Nutrition Branch, Centers for Disease Control and Prevention, Atlanta, Georgia.