1. Department of Pediatrics, Universidad del Valle Medical School, Cali, Colombia.
2. Associate Scientist, Tulane-COLCIENCIAS International Center for Infectious Disease Research, Cali, Colombia.
3. Department of Pediatrics, University of Colorado Health Sciences Center, Denver, CO 80262.
4. Associate Professor, Department of Medical Microbiology and Immunology, College of Medicine, Texas A & M University, College Station, TX 77843.