1. Epidemiology Section Department of Production Animal Studies Faculty of Veterinary Science University of Pretoria Onderstepoort South Africa
2. South African Equine Health and Protocols NPC Baker Square Cape Town South Africa
3. The Roslin Institute University of Edinburgh Edinburgh UK
4. AusVet Animal Health Services Canberra ACT Australia
5. Department of Tropical Diseases Faculty of Veterinary Science University of Pretoria Onderstepoort South Africa