1. Respiratory and Enteric Viruses Branch, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
2. Viral and Rickettsial Disease Laboratory, California Department of Health Services, Richmond, CA, USA
3. Clinical Virology Laboratory, University of Maryland Medical System, Baltimore, MD, USA
4. State of Maryland Department of Health and Mental Hygiene, Baltimore, MD, USA
5. Medical Virology Laboratory, Texas Department of Health, Austin, TX, USA
6. Wisconsin State Laboratory of Hygiene, University of Wisconsin-Madison, Madison, WI, USA
7. Wadsworth Center, New York State Department of Health, Albany, NY, USA
8. Public Health Laboratory, Minnesota Department of Health, Minneapolis, MN, USA
9. Missouri State Public Health Laboratory, Department of Health and Senior Services, Jefferson City, MO, USA