1. Division of Infectious Diseases; Department of Internal Medicine; University of Texas Medical Branch; Galveston; TX; USA
2. Department of Microbiology, Immunology and Biochemistry; University of Tennessee Health Science Center; Memphis; TN; USA
3. Division of Hematology/Oncology; University of Texas Medical Branch; Galveston; TX; USA
4. Department of Pathology; University of Texas Medical Branch; Galveston; TX; USA