1. Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
2. MRC International Nutrition Group, London School of Hygiene and Tropical Medicine, London, United Kingdom, and MRC Keneba, The Gambia
3. Institut für Chemie, Analytische Chemie, Karl-Franzens-Universität, Graz, Austria
4. International Center for Diarrhoeal Disease Research, Bangladesh