1. Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana
2. Agence Francaise de Securite Sanitaire des Aliments, Lyon, France
3. Wildlife Research Center, Colorado Division of Wildlife, Fort Collins, Colorado
4. Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, Iowa
5. Department of Veterinary Sciences, University of Wyoming, Laramie, Wyoming