1. Special Bacteriology Reference Laboratory, Bacterial Special Pathogens Branch, Division of High-Consequence Pathogens and Pathology, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA
2. National Collection of Type Cultures, Health Protection Agency, Colindale, London NW9 5EQ, UK
3. Division of Scientific Resources, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA
4. Institut National de la Recherche Agronomique, Unité de Virologie et Immunologie Moléculaires, Domaine de Vilvert, Jouy-en-Josas, France
5. Department of Microbial, Biochemical and Food Biotechnology, University of the Free State, Bloemfontein, South Africa
6. Institut für Angewandte Mikrobiologie, Universität Giessen, Giessen, Germany
7. Biology Department, Lycoming College, Williamsport PA 17701, USA