1. Instituto de Investigaciones en Ciencias de la Salud, Universidad Nacional de Asunción, San Lorenzo 111241, Paraguay
2. Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
3. Departamento de Laboratorio de Análisis Clínicos, Hospital Central—Instituto de Previsión Social, Asunción 001531, Paraguay
4. Department of Medicine, Division of Infectious Diseases, Emory University, 1760 Haygood Drive NE, Room E-169, Bay E-1, Atlanta, GA 30322, USA
5. Department of Pathology, Emory University, Atlanta, GA 30322, USA
6. Facultad de Ciencias Químicas, Universidad Nacional de Asunción, Campus Universitario, San Lorenzo 111421, Paraguay
7. Departamento de Epidemiología, Hospital Central—Instituto de Previsión Social, Asunción 001531, Paraguay
8. Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
9. Department of Medicine, Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA