1. Communicable Diseases Branch, Queensland Health, Brisbane, Queensland, Australia;
2. National Centre for Epidemiology and Population Health, College of Medicine, Biology and Environment, Australian National University, Canberra, Australian Capital Territory, Australia;
3. Queensland Paediatric Infectious Diseases Laboratory, Queensland Children's Medical Research Institute, University of Queensland, Royal Children's Hospital, Herston, Queensland, Australia; and
4. Clinical Medical Virology Centre, Sir Albert Sakzewski Virus Research Centre, University of Queensland, St Lucia, Queensland, Australia