1 School of Public Health, Curtin University, Bentley, Australia.
2 Wesfarmers Centre of Vaccines and Infectious Diseases, Telethon Kids Institute, University of Western Australia, Subiaco, Western Australia, Australia.
3 Rollins School of Public Health, Emory University, Atlanta Georgia, USA.
4 Communicable Disease Control Directorate, Department of Health Western Australia, Shenton Park, Australia.
5 School of Medicine, Notre Dame University, Fremantle, Western Australia.
6 School of Pathology and Laboratory Medicine, University of Western Australia, Crawley, Australia.