1 Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA.
2 Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA; Nebraska Public Health Laboratory, University of Nebraska Medical Center, Omaha, NE, USA.
3 Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA; Nebraska Public Health Laboratory, University of Nebraska Medical Center, Omaha, NE, USA. Electronic address: [email protected].