1. Division of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, Western Australia 6150,1
2. Department of Pathology, Vest-Agder County Central Hospital, N-4604 Kristiansand, Norway2; and
3. Department of Microbiology and Infectious Diseases, Royal Children’s Hospital, Parkville, Victoria 3052,3 and
4. Pathology and Laboratory Medicine Service, Department of Veterans Affairs Medical Center, Washington, D.C.4
5. Department of Anatomical Pathology, PathCentre, Nedlands, Western Australia 6009,5 Australia;