1. Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA
2. Department of Microbiology and Immunology, Center for Molecular and Tumor Virology and Feist-Weiller Cancer Center, Louisiana State University Health Sciences Center, Shreveport, Louisiana, USA
3. The Penn State Hershey Cancer Institute, Hershey, Pennsylvania, USA
4. Department of Public Health Sciences, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA
5. Division of Infectious Diseases, Department of Medicine, University of California–San Francisco, San Francisco, California, USA