1. Health Intelligence Team, Institute of Environmental Science and Research, Wellington, New Zealand
2. Department of Preventive and Social Medicine, University of Otago, Dunedin, New Zealand
3. Department of Paediatrics, Dunedin Hospital, Dunedin, New Zealand
4. Department of Internal Medicine, Amsterdam Infection and Immunity Institute, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
5. Department of Paediatrics, University of Otago, Christchurch, New Zealand