1. Department of Paediatrics; Imperial College London; St Mary's Campus London W2 1PG
2. National Veterinary Institute; Technical University of Denmark; Bulowsvej 27 DK-1790 Copenhagen V Denmark
3. Pathology Genomics Group; Institute for Biological Sciences; National Research Council of Canada; Ottawa Ontario K1A 0R6 Canada
4. Institute of Veterinary Bacteriology; University of Berne; Laenggasstrasse 122 3012 Berne Switzerland
5. State Key Laboratory of Agricultural Microbiology; College of Veterinary Medicine; Huazhong Agricultural University; Shizishan Street 1 Wuhan 430070 People's Republic of China
6. Department of Pathology and Infectious Diseases; Royal Veterinary College; North Mymms Hertfordshire AL9 7TA