1. Veterans Administration Western New York Healthcare System, Buffalo, New York, USA
2. Department of Medicine, University at Buffalo, State University of New York, Buffalo, New York, USA
3. Department of Microbiology and Immunology, University at Buffalo, State University of New York, Buffalo, New York, USA
4. The Witebsky Center for Microbial Pathogenesis, University at Buffalo, State University of New York, Buffalo, New York, USA
5. Multidrug-Resistant Organism Repository and Surveillance Network (MRSN), Walter Reed Army Institute of Research, Silver Spring, Maryland, USA