1. Produce Safety & Microbiology Research Unit, Western Regional Research Center, United States Department of Agriculture, Agricultural Research Service, Albany, California 94710, United States
2. Veterinary
Faculty, Centro de Investigación en Encefalopatías y
Enfermedades Transmisibles Emergentes (CIEETE), Universidad de Zaragoza, 50013, Zaragoza Spain
3. Virus
and Prion Research Unit, National Animal Disease Center, United States
Department of Agriculture, Agricultural Research Service, Ames, Iowa 50010, United States
4. CIMUS
Biomedical Research Institute, University of Santiago de Compostela-IDIS, Santiago de Compostela, 15782 Spain