1. Galveston National Laboratory, University of Texas Medical Branch, Galveston, Texas, USA
2. INRS-Institut Armand-Frappier, University of Quebec, Laval, Quebec, Canada
3. Veterinary Medicine Division, Paul-Ehrlich-Institute, Langen, Germany
4. Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, Texas, USA
5. Faculty of Veterinary Medicine, University of Calgary, Calgary, Alberta, Canada