1. Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
2. Elsie Widdowson Laboratory, Medical Research Council, Cambridge, UK
3. Department of Pathology, University of Cambridge, Cambridge, UK
4. MRC Unit The Gambia at the London School of Hygiene & Tropical Medicine, Fajara, Banjul, The Gambia
5. Biomineral Research Group, Department of Veterinary Medicine, University of Cambridge, Cambridge, UK