1. Department of Infectious Diseases, Infection Control and Employee Health, The University of Texas MD Anderson Cancer Center , Houston, TX , USA
2. Department of Leukemia, The University of Texas MD Anderson Cancer Center , Houston, TX , USA
3. Section of Clinical Microbiology and Virology, Division of Pathology and Laboratory Medicine, The University of Texas MD Anderson Cancer Center , Houston, TX , USA
4. Department of Molecular Medicine, University of Padua , Padua , Italy