1. Canadian Center for Vaccinology, IWK Health Centre and Nova Scotia Health Authority, Dalhousie University, Halifax, NS, Canada B3K 6R8
2. OXON Epidemiology Ltd., London NW1 2FD, UK
3. London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK
4. Pfizer Inc., Collegeville, PA 19426, USA
5. Pfizer Canada, Kirkland, QC, Canada H9J 2M5
6. Pfizer, 75668 Paris Cedex 14, France