1. Division of Infectious Diseases, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
2. William J von Liebig Center for Transplantation and Clinical Regeneration, Mayo Clinic, Rochester, Minnesota, USA
3. Gifu Pharmaceutical University, Gifu, Japan
4. Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama, USA
5. Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
6. Operative Unit of Microbiology and Virology, Department of Specialized, Experimental, and Diagnostic Medicine, Polyclinic of St Orsola-Malpighi, University of Bologna, Italy
7. Operative Unit of Obstetrics and Prenatal Medicine, Department of Medical Surgical Sciences, Polyclinic of St Orsola-Malpighi, University of Bologna, Italy
8. Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, Michigan, USA
9. Viral Vaccine Preventable Diseases Branch, Division of Viral Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA