1. National Centre for Epidemiology and Population Health, The Australian National University, Canberra, Australia.
2. OzFoodNet, Australian Government Department of Health and Ageing, Canberra, Australia.
3. OzFoodNet, Communicable Disease Prevention and Control Unit, Department of Health, Melbourne, Australia.
4. Communicable Disease Control Branch, Department of Health, Adelaide, Australia.
5. OzFoodNet, Communicable Disease Control Directorate, Department of Health, Perth, Australia.
6. OzFoodNet, Communicable Diseases Branch, Queensland Health, Brisbane, Australia.